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@article{nokey,

title = {Cobalt-Based Catalyst Integration Into a Hierarchically Ordered Macro-Meso-microporous Carbon Cathode for High-performance Aqueous Zn-Sulfur Batteries},

author = {L Z Liu and M Z Hussain and D Lei and O Henrotte and E Cortes and A S Bandarenka and R A Fischer},

url = {\<Go to ISI\>://WOS:001554583800001},

doi = {10.1002/advs.202509945},

year  = {2025},

date = {2025-08-21},

journal = {Advanced Science},

abstract = {The pyrolytic synthesis of an ordered macro-meso-micro porous carbon cathode material (OM-PC) with integration of a Co3ZnC/Co catalyst is reported. It is derived from a Co-doped ZIF-8 framework via a templated in situ growth within the interstitial spaces of a preformed self-assembled polystyrene monolith, followed by the template removal. The hierarchical 3D architecture facilitates Zn2(+) diffusion and enhances reaction kinetics during charge-discharge processes. The integrated Co3ZnC/Co catalyst significantly improves the surface affinity of the porous carbon host for polysulfide trapping and accelerates polysulfide redox conversion, leading to enhanced sulfur utilization, mitigated shuttle effects, and longer cycling stability. The fabricated aqueous Zn-S battery with the sulfur-loaded cathode denoted as S@Co3ZnC/Co/OM-PC delivers a synergistic high discharge capacity of approximate to 1685 mA h g-1, which includes approximate to 115 mA h g-1 contributed from the I3 -/I- redox couple. The device shows low polarization and exhibits a minimal capacity decay of approximate to 0.027% per cycle over 400 cycles. It maintained a good rate performance of approximate to 1035 mA h g-1 at 3 A g-1, with long cycling stability. In-depth investigation reveals a multistep intermediate polysulfides conversion pathway in the aqueous electrolyte, which effectively avoids the sluggish solid-solid conversion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Photosystem II-Carbon Nitride Photoanodes for Scalable Biophotoelectrochemistry},

author = {H Y Zhang and W J Tian and J K Lin and P Zhang and G S Shao and S K Ravi and H Q Sun and E Cort\'{e}s and V Andrei and S B Wang},

url = {\<Go to ISI\>://WOS:001550386200001},

doi = {10.1002/adma.202508813},

issn = {0935-9648},

year  = {2025},

date = {2025-08-15},

journal = {Advanced Materials},

abstract = {Photosystem II (PSII) is a vital photosynthetic enzyme with the potential for sustainable bioelectricity and fuel generation. However, interfacing PSII with intricate, small-scale electrodes for practical applications has been challenging. This study addresses this by creating protonated macroporous carbon nitride (MCN) as support and developing a scalable spray-freeze method to wire PSII with MCN. This facilitates the production of large-area MCN-PSII photoanodes up to 33 cm2 for biophotoelectrochemical water oxidation to O2, achieving efficient interfacial charge transfer and initial photocurrents in the mA range with Faradaic yield of 93.5 +/- 8.5% over 5 h. A bias-free biophotoelectrochemical (BPEC) device is designed by connecting the MCN-PSII photoanode to a carbon nanotube cathode loaded with bilirubin oxidase. An array of eight tandem BPEC cells with a photoactive area of 72 cm2 successfully powers low-power electronics, such as LEDs. This work paves an efficient way for bioelectrode fabrication, showcasing the potential of PSII-based semi-artificial systems for BPEC and biophotovoltaic applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Reflection-Enhanced Raman Identification of Single Bacterial Cells Patterned Using Capillary Assembly},

author = {J Lee and E Rho and M Kim and S Huh and S Kim and S A Maier and E Cort\'{e}s and S Jo and Y S Jung and Y Nam},

url = {\<Go to ISI\>://WOS:001543629000001},

doi = {10.1021/acssensors.5c01225},

issn = {2379-3694},

year  = {2025},

date = {2025-08-03},

journal = {Acs Sensors},

abstract = {Raman spectroscopy is an enticing tool for the rapid identification of pathogenic bacteria and has the potential to meet the demand for early diagnosis and timely treatment of patients. However, it remains a challenge to devise a reliable Raman detection platform to obtain reproducible signals from single bacterial cells. Herein, we utilize a reflective Ag/SiO2 film that enhances the intrinsically weak Raman signals by re-excitation of the bacteria and reflection of downward-scattered photons, with maximum Raman intensities recorded by exciting the central edge of each single cell. The reflection-based configuration is simple, and its reliability as a sensing platform is validated by deep learning analysis. Importantly, given the positional dependence of the laser light on the Raman intensity, we employ capillarity-assisted particle assembly (CAPA) to selectively position single bacterial cells into a reflective topographical template to align the most Raman active region of the cell per the trap site geometry. Moreover, CAPA is utilized to directly isolate single cells from a suspension of artificial urine, eradicating any additional steps previously required to separate bacteria from biological samples. The proposed system has positive implications for future clinical settings that require simple, accurate, and reproducible detection of bacteria at the single-cell level.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Spatially resolved photocatalytic active sites and quantum efficiency in a 2D semiconductor},

author = {O Henrotte and S Saris and F Gr\"{o}bmeyer and C G Gruber and I Bilgin and A H\"{o}gele and N J Halas and P Nordlander and E Cort\'{e}s and A Naldoni},

url = {\<Go to ISI\>://WOS:001538017700012},

doi = {10.1038/s41467-025-62284-x},

year  = {2025},

date = {2025-07-26},

journal = {Nature Communications},

volume = {16},

number = {1},

abstract = {Identifying reactive sites and measuring their activities is crucial for enhancing the efficiency of every catalyst. Reactivity maps can guide the development of next-generation photocatalysts like 2D transition metal dichalcogenides, which suffer from low conversion rates. While their electrocatalytic sites are well-studied, their photocatalytic sites remain poorly understood. Using scanning photoelectrochemical microscopy, we spatially resolve the photoreactivity of MoS2 monolayers, a prototypical 2D transition metal dichalcogenide, for redox reactions, including H2 production from water. Aligned-unaligned excitation-detection measurements reveal that photogenerated holes and electrons exhibit distinct behaviors. Oxidation products localize at the excitation spot, indicating stationary holes, while photoreduction occurs up to at least 80 microns away, showing exceptional electron mobility. We also elucidate the photochemical reactivity according to the nature of the electronic excitation, showing that the internal quantum efficiency of strongly-bound A-excitons outperforms weakly-bound (free-carrier like) C-excitons across the flake. These findings offer novel guidance to rationally design 2D photocatalysts via engineering their optical and charge extraction abilities for efficient solar energy conversion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Defects Dynamic in Photo-Excited CeO2 and their Influence on CO2 Photoreduction},

author = {R Yalavarthi and S B Mishra and O Henrotte and E Cortes},

url = {\<Go to ISI\>://WOS:001527447200001},

doi = {10.1002/adfm.202513933},

issn = {1616-301X},

year  = {2025},

date = {2025-07-14},

journal = {Advanced Functional Materials},

abstract = {Defects play a crucial role in shaping the efficiency and performance of semiconductor-based technologies. Under illumination, the interaction between photo-excited charge carriers and defect states in the semiconductor can significantly influence the response of devices and catalysts. Here, an X-ray photoelectron spectroscopy study conducted under light excitation is presented to track exciton generation and its interaction with defects in CeO2, a widely used metal-oxide support in (photo) catalysis. The light intensity-dependent measurements reveal that photo-excited electrons in CeO2 can effectively reduce Ce4+ to Ce3+. Surface-enhanced Raman spectroscopy further highlights the critical role of Ce3+ states in governing charge and energy transport across the CeO2-molecule interface. Finally, how these photo-induced states (Ce3+) can be leveraged is demonstrated to control the selectivity in the photocatalytic CO2 reduction reaction, dramatically influencing the yields of CO, CH4, and H2.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Near-Unity Nitrate to Ammonia conversion via reactant enrichment at the solid-liquid interface},

author = {W R Liao and J Wang and Y Tan and X Zi and C X Liu and Q Y Wang and L Zhu and C W Kao and T S Chan and H M Li and Y L Zhang and K Liu and C Cai and J W Fu and B D Xi and E Cortes and L Y Chai and M Liu},

url = {\<Go to ISI\>://WOS:001523450400034},

doi = {10.1038/s41467-025-60671-y},

year  = {2025},

date = {2025-07-01},

journal = {Nature Communications},

volume = {16},

number = {1},

abstract = {Electroreduction of nitrate (NO3-) to ammonia (NH3) is a promising approach for addressing energy challenges. However, the activity is limited by NO3- mass transfer, particularly at reduction potential, where an abundance of electrons on the cathode surface repels NO3- from the inner Helmholtz plane (IHP). This constraint becomes pronounced as NO3- concentration decreases, impeding practical applications in the conversion of NO3\textendashto-NH3. Herein, we propose a generic strategy of catalyst bandstructure engineering for the enrichment of negatively charged ions through solid-liquid (S-L) junction-mediated charge rearrangement within IHP. Specifically, during NO3- reduction, the formation of S-L junction induces hole transfer from Ag-doped MoS2 (Ag-MoS2) to electrode/electrolyte interface, triggering abundant positive charges on the IHP to attract NO3-. Thus, Ag-MoS2 exhibits a similar to 28.6-fold NO3- concentration in the IHP than the counterpart without junction, and achieves near-100% NH3 Faradaic efficiency with an NH3 yield rate of similar to 20 mg h(-1) cm(-2) under ultralow NO3- concentrations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Sulfur Mediated Interfacial Proton-Directed Transfer Boosts Electrocatalytic Nitric Oxide Reduction to Ammonia over Dual-Site Catalysts},

author = {Z L Wang and H Y Duan and W Q Qu and D L Han and X C Li and L Zhu and X Jiang and D H Cheng and Y J Shen and M Xie and E Cortes and D S Zhang},

url = {\<Go to ISI\>://WOS:001524469700001},

doi = {10.1002/anie.202511398},

year  = {2025},

date = {2025-07-01},

journal = {Angewandte Chemie-International Edition},

abstract = {Electrocatalytic nitric oxide reduction reaction (NORR) for ammonia (NH3) synthesis represents a sustainable strategy that simultaneously realizes the nitrogen cycle and resource integration. The key issue hindering the NORR efficiency is accelerating proton (*H) transfer to facilitate NO hydrogenation while inhibiting the hydrogen evolution reaction (HER). Herein, we demonstrate an interface-engineered sulfur-mediated Cu@Co electrocatalyst (S-Cu@Co/C) that boosts NORR performance through dual modulation of electronic structure and proton transfer on active sites. A comprehensive program of experimental and theoretical calculations was employed to discover that sulfur incorporation induces electron redistribution in the Cu-Co interface, creating electron-rich sulfur and electron-deficient metals. This electronic configuration synergistically enhances NO adsorption on Cu sites and promotes water dissociation on Co sites. More critically, sulfur could direct the rapid transfer of *H from Co to Cu sites, thereby accelerating the NO hydrogenation and suppressing HER. Consequently, S-Cu@Co/C achieves an NH3 yield rate of 655.3 mu mol h-1 cm-2 in a flow cell and a Faradaic efficiency of 92.4% in an H-cell. Remarkably, the catalyst could maintain continuous electrolysis tests and steady NH3 yield up to 100 h. This work provides innovative insights into the fabrication of efficient electrocatalysts via heteroatom-mediated interfacial engineering strategies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Biomass Native Structure Into Functional Carbon-Based Catalysts for Fenton-Like Reactions},

author = {W J Tian and J K Lin and Z H Tian and S Ncube and H Y Zhang and E Cort\'{e}s and H Q Sun and S B Wang},

url = {\<Go to ISI\>://WOS:001506052500001},

doi = {10.1002/adfm.202508759},

issn = {1616-301X},

year  = {2025},

date = {2025-06-10},

journal = {Advanced Functional Materials},

abstract = {Advancing biomass-derived carbon materials requires a systematic understanding of how distinct biomass structures influence their properties and functionality. To address this, eight 2D flaky and 1D acicular plant biomasses is systematically compared to synthesize pristine carbon, N-doped carbon, and cobalt/graphitic carbon for Fenton-like peroxymonosulfate (PMS) activation. Biomass pyrolysis under 5% NH3 generates surface N-doped amorphous carbon, facilitating a selective electron transfer pathway (ETP), where high N incorporation, specific surface area, and atomic-level control over O groups synergistically enhance its efficiency. While COOH groups contribute positively, excessive defects and C \& boxH;O groups hinder ETP performance. Notably, compared to 2D biomass, 1D acicular biomass induces tubular carbon with lower C \& boxH;O content, promoting the ETP regime. 2D flaky biomass facilitates Co nanoparticle incorporation in cobalt/graphitic carbon, where high contents of N, Co, defects, and oxygen groups (C \& boxH;O/C \& horbar;O/COOH) enhance sulfate radical (SO4 center dot-)-dominated catalysis, whereas excessive sp(2) C (\>75-80 at.%) negatively affects performance. Through structural characterization, mechanistic analysis, and quantitative linear fitting correlations, this study identifies biomass-derived key active site interactions governing electron transfer and SO4 center dot\textendashdriven oxidation mechanisms. These insights establish a framework for sustainable, biomass-structure-driven carbon design for environmental catalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Transfer dynamics of photo-generated carriers in catalysis},

author = {J Wang and W R Liao and Y Tan and O Henrotte and Y C Kang and K Liu and J W Fu and Z Lin and L Y Chai and E Cortes and M Liu},

url = {\<Go to ISI\>://WOS:001504105600001},

doi = {10.1039/d5cs00512d},

issn = {0306-0012},

year  = {2025},

date = {2025-06-09},

journal = {Chemical Society Reviews},

abstract = {Semiconductor based photo-assisted catalytic reaction, leveraging solar energy for chemical fuel production and pollutant treatment, relies heavily on carrier separation and migration. Despite extensive efforts to enhance carrier separation, understanding carrier transfer dynamics remains limited, hindering large-scale application. This review systematically examines carrier transfer dynamics characterization, highlighting semiconductors' intrinsic properties, carrier relaxation methods, and spatiotemporal visualization. We also discuss plasmonic metal catalysts, a novel photocatalyst class with unique carrier dynamics. Furthermore, we evaluate advanced techniques and metrics for assessing carrier transfer, offering insights for developing high-performance catalysts. Finally, we provide a summary and outlook on future developments and standards in carrier transfer dynamics characterization for improved photo-related catalytic applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Cascade Electrocatalytic Reduction of Nitrate to Ammonia Using Bimetallic Covalent Organic Frameworks with Tandem Active Sites},

author = {J Zhong and H Y Duan and M Q Cai and Y Zhu and Z L Wang and X C Li and Z L Zhang and W Q Qu and K Zhang and D L Han and D H Cheng and Y J Shen and M Xie and E Cortes and D S Zhang},

url = {\<Go to ISI\>://WOS:001510656800001},

doi = {10.1002/anie.202507956},

year  = {2025},

date = {2025-06-05},

journal = {Angewandte Chemie-International Edition},

abstract = {Electrochemical nitrate reduction reaction (NO3RR) is a promising approach to simultaneously realize pollutant removal and ammonia generation. However, this process involves the transfer of eight electrons and nine protons along with multiple by-products, resulting in a significant challenge for achieving high ammonia yield and selectivity. Herein, we introduced bimetallic covalent organic frameworks catalysts with Cu and Co active sites to achieve a two-step tandem reaction, avoiding excessive nitrite accumulation and enabling efficient NO3RR. For the initial two-electron process, the Cu sites in the bimetallic catalyst exhibit a strong binding affinity with nitrate, promoting their conversion to nitrite. The Co sites enhance the supply and adsorption of active hydrogen and stabilize the subsequent six-electron process, thereby improving the overall catalytic efficiency. Compared to monometallic Cu and Co catalysts, the CuCo bimetallic catalyst demonstrates superior ammonia yield and Faradaic efficiency (NH3 yield rate = 20.8 mgh-1cm-2},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Angular dispersion suppression in deeply subwavelength phonon polariton bound states in the continuum metasurfaces},

author = {L Nan and A Mancini and T Weber and G L Seah and E Cort\'{e}s and A Tittl and S A Maier},

doi = {10.1038/s41566-025-01670-9},

issn = {1749-4885 

1749-4893},

year  = {2025},

date = {2025-05-16},

journal = {NATURE PHOTONICS},

abstract = {Quasi-bound states in the continuum (qBICs) achieved through symmetry breaking in photonic metasurfaces are a powerful approach for engineering resonances with high quality factors and tunability. However, miniaturization of these devices is limited as the in-plane unit-cell size typically scales linearly with the resonant wavelength. By contrast, polariton resonators can be deeply subwavelength, offering a promising solution for achieving compact devices. Here we demonstrate that low-loss mid-infrared surface phonon polaritons enable metasurfaces supporting qBICs with unit-cell volumes up to 105 times smaller than the free-space volume lambda 03documentclass[12pt]minimal usepackageamsmath usepackagewasysym usepackageamsfonts usepackageamssymb usepackageamsbsy usepackagemathrsfs usepackageupgreek setlength\oddsidemargin-69pt begindocument$$\lambda_0\<^\>3$$enddocument. Using 100-nm-thick free-standing silicon carbide membranes, we achieve highly confined qBIC states with exceptional robustness against incident-angle variations, a feature unique among qBIC systems. This absence of angular dispersion enables mid-infrared vibrational sensing of thin, weakly absorbing molecular layers using a reflective objective, a method that typically degrades resonance quality in standard qBIC metasurfaces. We introduce surface-phonon-polariton-based qBICs as a platform for ultraconfined nanophotonic systems, advancing the miniaturization of mid-infrared sensors and devices for thermal radiation engineering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Non-Precious Metal Catalysts with Gradient Oxidative Dual Sites Boost Bimolecular Activation for Catalytic Oxidation Reactions},

author = {Y Wang and T Lan and L Han and E Pensa and Y Shen and X Li and Z Xu and X Chen and M Wang and X Xue and Y Li and M Xie and E Cort\'{e}s and D Zhang},

url = {https://doi.org/10.1002/anie.202506018},

doi = {https://doi.org/10.1002/anie.202506018},

issn = {1433-7851},

year  = {2025},

date = {2025-04-09},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

pages = {e202506018},

abstract = {Abstract Catalytic oxidation emerges as a highly promising and cost-effective approach for eliminating gaseous pollutants, greenhouse gases, and volatile organic compounds (VOCs) from industrial exhaust streams. However, achieving the simultaneous activation of O2 and substrate molecules at low temperatures using non-precious metal catalysts remains a significant challenge. In this study, we introduce gradient oxidative Cu─O─Ti/Cu─O─Cu dual sites that enhance bimolecular activation for catalytic oxidation reactions. The catalyst, Ti-doped CuO, is synthesized on a TiO2 support through the immobilization of Cu2? on NO3?-grafted TiO2, followed by thermal treatment. The resulting gradient oxidative Cu─O─Ti/Cu─O─Cu sites exhibit exceptional catalytic oxidation activity for NH3 and various VOCs at low temperatures, matching the performance of precious metal-based catalysts. Notably, during NH? oxidation, Cu─O─Ti sites enhance the activation of both O? and NH?. HNO intermediates formed on Cu─O─Ti sites react with NH intermediates on neighboring Cu─O─Cu sites?producing N? and H?O via an imide mechanism?which effectively lowers the reaction barrier for catalytic NH? oxidation. As such, dual sites in non-precious metal catalysts show promising results for advancing future catalytic oxidation technologies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Lanthanide single-atom catalysts for efficient CO2-to-CO electroreduction},

author = {Q Wang and T Luo and X Cao and Y Gong and Y Liu and Y Xiao and H Li and F Gr\"{o}bmeyer and Y-R Lu and T-S Chan and C Ma and K Liu and J Fu and S Zhang and C Liu and Z Lin and L Chai and E Cortes and M Liu},

url = {https://doi.org/10.1038/s41467-025-57464-8},

doi = {10.1038/s41467-025-57464-8},

issn = {2041-1723},

year  = {2025},

date = {2025-03-27},

journal = {Nature Communications},

volume = {16},

number = {1},

pages = {2985},

abstract = {Single-atom catalysts (SACs) have received increasing attention due to their 100% atomic utilization efficiency. The electrochemical CO2 reduction reaction (CO2RR) to CO using SAC offers a promising approach for CO2 utilization, but achieving facile CO2 adsorption and CO desorption remains challenging for traditional SACs. Instead of singling out specific atoms, we propose a strategy utilizing atoms from the entire lanthanide (Ln) group to facilitate the CO2RR. Density functional theory calculations, operando spectroscopy, and X-ray absorption spectroscopy elucidate the bridging adsorption mechanism for a representative erbium (Er) single-atom catalyst. As a result, we realize a series of Ln SACs spanning 14 elements that exhibit CO Faradaic efficiencies exceeding 90%. The Er catalyst achieves a high turnover frequency of ~130,000 h−1 at 500 mA cm−2. Moreover, 34.7% full-cell energy efficiency and 70.4% single-pass CO2 conversion efficiency are obtained at 200 mA cm−2 with acidic electrolyte. This catalytic platform leverages the collective potential of the lanthanide group, introducing new possibilities for efficient CO2-to-CO conversion and beyond through the exploration of unique bonding motifs in single-atom catalysts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Catalytic Hydrolysis of Perfluorinated Compounds in a Yolk\textendashShell Micro-Reactor},

author = {J Zheng and X Wang and X Zi and H Zhang and H Chen and E Pensa and K Liu and J Fu and Z Lin and L Chai and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1002/advs.202413203},

doi = {https://doi.org/10.1002/advs.202413203},

issn = {2198-3844},

year  = {2025},

date = {2025-03-01},

journal = {Advanced Science},

volume = {12},

number = {9},

pages = {2413203},

abstract = {Abstract Perfluorinated compounds (PFCs) are emerging environmental pollutants characterized by their extreme stability and resistance to degradation. Among them, tetrafluoromethane (CF4) is the simplest and most abundant PFC in the atmosphere. However, the highest C─F bond energy and its highly symmetrical structure make it particularly challenging to decompose. In this work, a yolk?shell Al2O3 micro-reactor is developed to enhance the catalytic hydrolysis performance of CF4 by creating a local autothermic environment. Finite element simulations predict that the yolk?shell Al2O3 micro-reactor captures the heat released during the catalytic hydrolysis of CF4, resulting in a local autothermic environment within the yolk?shell structure that is 50 °C higher than the set temperature. The effectiveness of this local autothermic environment is experimentally confirmed by in situ Raman spectroscopy. As a result, the obtained yolk?shell Al2O3 micro-reactor achieves 100% CF4 conversion at a considerably low temperature of 580 °C for over 150 h, while hollow and solid Al2O3 structures required higher temperatures of 610 and 630 °C, respectively, to achieve the same conversion rate, demonstrating the potential of yolk?shell Al2O3 micro-reactor to significantly reduce the energy requirements for PFCs degradation and contribute to more sustainable and effective environmental remediation strategies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Metal vacancies in semiconductor oxides enhance hole mobility for efficient photoelectrochemical water splitting},

author = {J Wang and K Liu and W Liao and Y Kang and H Xiao and Y Chen and Q Wang and T Luo and J Chen and H Li and T-S Chan and S Chen and E Pensa and L Chai and F Liu and L Jiang and C Liu and J Fu and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1038/s41929-025-01300-1},

doi = {10.1038/s41929-025-01300-1},

issn = {2520-1158},

year  = {2025},

date = {2025-03-01},

journal = {Nature Catalysis},

volume = {8},

number = {3},

pages = {229-238},

abstract = {Achieving efficient carrier separation in transition-metal-oxide semiconductors is crucial for their applications in optoelectronic and catalytic devices. However, the substantial disparity in mobility between holes and electrons heavily limits device performance. Here we develop a general strategy for enhancing hole mobility via reducing their effective mass through metal vacancy (VM) management. The introduction of VM yields remarkable improvements in hole mobility: 430% for WO3, 350% for TiO2 and 270% for Bi2O3. To illustrate the importance of this finding, we applied the VM concept to photoelectrochemical water splitting, where efficient carrier separation is highly coveted. In particular, VM-WO3 achieves a 4.4-fold enhancement in photo-to-current efficiency, yielding a performance of 4.8 mA cm−2 for both small- and large-scale photoelectrodes with exceptional stability for over 120 h.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Boosting Electrocatalytic Nitrate Reduction through Enhanced Mass Transfer in Cu-Bipyridine 2D Covalent Organic Framework Films},

author = {Y Zhu and H Duan and C G Gruber and W Qu and H Zhang and Z Wang and J Zhong and X Zhang and L Han and D Cheng and D D Medina and E Cort\'{e}s and D Zhang},

url = {https://doi.org/10.1002/anie.202421821},

doi = {https://doi.org/10.1002/anie.202421821},

issn = {1433-7851},

year  = {2024},

date = {2024-12-24},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

pages = {e202421821},

abstract = {Abstract Electrocatalytic nitrate reduction (NO3RR) is a promising method for pollutant removal and ammonia synthesis and involves the transfer of eight electrons and nine protons. As such, the rational design of catalytic interfaces with enhanced mass transfer is crucial for achieving high ammonia yield rates and Faradaic efficiency (FE). In this work, we incorporated a Cu-bipyridine catalytic interface and fabricated crystalline 2D covalent organic framework films with significantly exposed catalytic sites, leading to improved FE and ammonia yield (FE=92.7?%, NH3 yield rate=14.9?mg???h?1cm?2 in 0.5?M nitrate) compared to bulk catalysts and outperforming most reported NO3RR electrocatalysts. The film-like morphology enhances mass transfer across the Cu-bipyridine interface, resulting in superior catalytic performance. We confirmed the reaction pathway and mechanism through in situ characterizations and theoretical calculations. The Cu sites act as primary centers for adsorption and activation, while the bipyridine sites facilitate water adsorption and dissociation, supplying sufficient H* and accelerating proton-coupled electron transfer kinetics. This study provides a viable strategy to enhance mass transfer at the catalytic interface through rational morphology control, boosting the intrinsic activity of catalysts in the NO3RR process.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Ion-Transport Kinetics and Interface Stability Augmentation of Zinc Anodes Based on Fluorinated Covalent Organic Framework Thin Films},

author = {D Lei and W Shang and L Cheng and Poonam and W Kaiser and P Banerjee and S Tu and O Henrotte and J Zhang and A Gagliardi and J Jinschek and E Cort\'{e}s and P M\"{u}ller-Buschbaum and A S Bandarenka and M Z Hussain and R A Fischer},

url = {https://doi.org/10.1002/aenm.202403030},

doi = {https://doi.org/10.1002/aenm.202403030},

issn = {1614-6832},

year  = {2024},

date = {2024-12-01},

journal = {Advanced Energy Materials},

volume = {14},

number = {46},

pages = {2403030},

abstract = {Abstract Zinc (Zn) emerges as an ideal anode for aqueous-based energy storage devices because of its safety, non-toxicity, and cost-effectiveness. However, the reversibility of zinc anodes is constrained by unchecked dendrite proliferation and parasitic side reactions. To minimize these adverse effects, a highly oriented, crystalline 2D porous fluorinated covalent organic framework (denoted as TpBD-2F) thin film is in situ synthesized on the Zn anode as a protective layer. The zincophilic and hydrophobic TpBD-2F provides numerous 1D fluorinated nanochannels, which facilitate the hopping/transfer of Zn2+ and repel H2O infiltration, thus regulating Zn2+ flux and inhibiting interfacial corrosion. The resulting TpBD-2F protective film enabled stable plating/stripping in symmetric cells for over 1200 h at 2 mA cm?2. Furthermore, assembled full cells (Zn-ion capacitors) deliver an ultra-long cycling life of over 100 000 cycles at a current density of 5 A g?1, outperforming nearly all reported porous crystalline materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Coherent Acoustic Phonons in Plasmonic Nanoparticles: Elastic Properties and Dissipation at Low Temperatures},

author = {H D Boggiano and T Possmayer and L Morguet and L Nan and L Sortino and S A Maier and E Cort\'{e}s and G Grinblat and A V Bragas and L De S. Menezes},

url = {https://doi.org/10.1021/acsnano.4c09193},

doi = {10.1021/acsnano.4c09193},

issn = {1936-0851},

year  = {2024},

date = {2024-11-19},

journal = {ACS Nano},

volume = {18},

number = {46},

pages = {31903-31911},

abstract = {We studied the frequency and quality factor of mechanical plasmonic nanoresonators as a function of temperature, ranging from ambient to 4 K. Our investigation focused on individual gold nanorods and nanodisks of various sizes. We observed that oscillation frequencies increase linearly as temperature decreases until saturation is reached at cryogenic temperatures. This behavior is explained by the temperature dependence of the elastic modulus, with a Debye temperature compatible with reported bulk values for gold. To describe the behavior of the quality factor, we developed a model considering the nanostructures as anelastic solids, identifying a dissipation peak around 150 K due to a thermally activated process, likely of the Niblett-Wilks mechanism type. Importantly, our findings suggest that external dissipation factors are more critical to improving quality factors than internal friction, which can be increased by modifying the nanoresonator’s environment. Our results enable the future design of structures with high vibration frequencies and quality factors by effectively controlling external losses.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Impact of Surface Enhanced Raman Spectroscopy in Catalysis},

author = {A Stefancu and J Aizpurua and I Alessandri and I Bald and J J Baumberg and L V Besteiro and P Christopher and M Correa-Duarte and B De Nijs and A Demetriadou and R R Frontiera and T Fukushima and N J Halas and P K Jain and Z H Kim and D Kurouski and H Lange and J-F Li and L M Liz-Marz\'{a}n and I T Lucas and A J Meixner and K Murakoshi and P Nordlander and W J Peveler and R Quesada-Cabrera and E Ringe and G C Schatz and S Schl\"{u}cker and Z D Schultz and E X Tan and Z-Q Tian and L Wang and B M Weckhuysen and W Xie and X Y Ling and J Zhang and Z Zhao and R-Y Zhou and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsnano.4c06192},

doi = {10.1021/acsnano.4c06192},

issn = {1936-0851},

year  = {2024},

date = {2024-10-29},

journal = {ACS Nano},

volume = {18},

number = {43},

pages = {29337-29379},

abstract = {Catalysis stands as an indispensable cornerstone of modern society, underpinning the production of over 80% of manufactured goods and driving over 90% of industrial chemical processes. As the demand for more efficient and sustainable processes grows, better catalysts are needed. Understanding the working principles of catalysts is key, and over the last 50 years, surface-enhanced Raman Spectroscopy (SERS) has become essential. Discovered in 1974, SERS has evolved into a mature and powerful analytical tool, transforming the way in which we detect molecules across disciplines. In catalysis, SERS has enabled insights into dynamic surface phenomena, facilitating the monitoring of the catalyst structure, adsorbate interactions, and reaction kinetics at very high spatial and temporal resolutions. This review explores the achievements as well as the future potential of SERS in the field of catalysis and energy conversion, thereby highlighting its role in advancing these critical areas of research.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Tandem microplastic degradation and hydrogen production by hierarchical carbon nitride-supported single-atom iron catalysts},

author = {J Lin and K Hu and Y Wang and W Tian and T Hall and X Duan and H Sun and H Zhang and E Cort\'{e}s and S Wang},

url = {https://doi.org/10.1038/s41467-024-53055-1},

doi = {10.1038/s41467-024-53055-1},

issn = {2041-1723},

year  = {2024},

date = {2024-10-10},

journal = {Nature Communications},

volume = {15},

number = {1},

pages = {8769},

abstract = {Microplastic pollution, an emerging environmental issue, poses significant threats to aquatic ecosystems and human health. In tackling microplastic pollution and advancing green hydrogen production, this study reveals a tandem catalytic microplastic degradation-hydrogen evolution reaction (MPD-HER) process using hierarchical porous carbon nitride-supported single-atom iron catalysts (FeSA-hCN). Through hydrothermal-assisted Fenton-like reactions, we accomplish near-total ultrahigh-molecular-weight-polyethylene degradation into C3-C20 organics with 64% selectivity of carboxylic acid under neutral pH, a leap beyond current capabilities in efficiency, selectivity, eco-friendliness, and stability over six cycles. The system demonstrates versatility by degrading various daily-use plastics across different aquatic settings. The mixture of FeSA-hCN and plastic degradation products further achieves a hydrogen evolution of 42 μmol h‒1 under illumination, outperforming most existing plastic photoreforming methods. This tandem MPD-HER process not only provides a scalable and economically feasible strategy to combat plastic pollution but also contributes to the hydrogen economy, with far-reaching implications for global sustainability initiatives.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {All-Optical Generation and Detection of Coherent Acoustic Vibrations in Single Gallium Phosphide Nanoantennas Probed Near the Anapole Excitation},

author = {H D Boggiano and N A Roqueiro and H Zhang and L Krivitsky and E Cortes and S A Maier and A V Bragas and A Kuznetsov and G Grinblat},

year  = {2024},

date = {2024-10-03},

journal = {arXiv preprint arXiv:2410.02431},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Polyoxometalates-Mediated Selectivity in Pt Single-Atoms on Ceria for Environmental Catalysis},

author = {T Lan and R Yalavarthi and Y Shen and M Gao and F Wang and Q Hu and P Hu and M Beladi-Mousavi and X Chen and X Hu and H Yang and E Cort\'{e}s and D Zhang},

url = {https://doi.org/10.1002/anie.202415786},

doi = {https://doi.org/10.1002/anie.202415786},

issn = {1433-7851},

year  = {2024},

date = {2024-09-26},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

pages = {e202415786},

abstract = {Abstract Optimizing the reactivity and selectivity of single-atom catalysts (SACs) remains a crucial yet challenging issue in heterogeneous catalysis. This study demonstrates selective catalysis facilitated by a polyoxometalates-mediated electronic interaction (PMEI) in a Pt single-atom catalyst supported on CeO2 modified with Keggin-type phosphotungstate acid (HPW), labeled as Pt1/CeO2-HPW. The PMEI effect originates from the unique arrangement of isolated Pt atoms and HPW clusters on the CeO2 support. Electrons are transferred from the ceria support to the electrophilic tungsten in HPW clusters, and subsequently, Pt atoms donate electrons to the now electron-deficient ceria. This phenomenon enhances the positive charge of Pt atoms, moderating O2 activation and limiting lattice oxygen mobility compared to the conventional Pt1/CeO2 catalyst. The resulting electronic structure of Pt combined with the strong and local acidic environment of HPW on Pt1/CeO2-HPW leads to improved efficiency and N2 selectivity in the degradation of NH3 and NO, as well as increased CO2 yield when inputting volatile organic compounds. This study sheds the light on the design of SACs with balanced reactivity and selectivity for environmental catalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Accelerating Toluene Oxidation over Boron\textendashTitanium\textendashOxygen Interface: Steric Hindrance of the Methyl Group Induced by the Plane-Adsorption Configuration},

author = {W Qu and Z Xu and C G Gruber and H Li and X Hu and L Zhou and H Duan and J Zhang and M Liu and E Cort\'{e}s and D Zhang},

url = {https://doi.org/10.1021/acs.est.4c06079},

doi = {10.1021/acs.est.4c06079},

issn = {0013-936X},

year  = {2024},

date = {2024-09-10},

journal = {Environmental Science \& Technology},

volume = {58},

number = {36},

pages = {16215-16224},

abstract = {Elimination of dilute gaseous toluene is one of the critical concerns within the field of indoor air remediation. The typical degradation route on titanium-based catalysts, “toluene\textendashbenzaldehyde\textendashcarbon dioxide”, necessitates the oxidation of the methyl group as a prerequisite for photocatalytic toluene oxidation. However, the inherent planar adsorption configuration of toluene molecules, dominated by the benzene rings, leads to significant steric hindrance for the methyl group. This steric hindrance prevents the methyl group from contacting the active species on the catalyst surface, thereby limiting the removal of toluene under indoor conditions. To date, no effective strategy to control the steric hindrance of the methyl group has been identified. Herein, we showed a B\textendashTi\textendashO interface that exhibits significantly enhanced toluene removal efficiency under indoor conditions. In-depth investigations revealed that, compared to typical Ti-based photocatalysts, the steric hindrance between the methyl group and the catalyst surface decreased from 3.42 to 3.03 r{A} on the designed interface. This reduction originates from the matching of orbital energy levels between Ti 3dz2 and C 2pz of the benzene ring. The decreased steric hindrance improved the efficiency of toluene being attacked by surface active species, allowing for rapid conversion into benzaldehyde and benzoic acid species for subsequent reactions. Our work provides novel insights into the steric hindrance effect in the elimination of aromatic volatile organic compounds.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Photonic solutions help fight climate crisis},

author = {G Tagliabue and H A Atwater and A Polman and E Cort\'{e}s},

url = {https://doi.org/10.1038/s41566-024-01509-9},

doi = {10.1038/s41566-024-01509-9},

issn = {1749-4893},

year  = {2024},

date = {2024-09-01},

journal = {Nature Photonics},

volume = {18},

number = {9},

pages = {879-882},

abstract = {The mitigation of climate change requires major transformations in the ways we generate energy and operate technologies that release carbon dioxide. Photonic concepts and novel light-driven technologies provide many potential solutions, transforming our current modes of energy use into more effective and sustainable ones.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Tracking surface charge dynamics on single nanoparticles},

author = {R Dagar and W Zhang and P Rosenberger and T M Linker and A Sousa-Castillo and M Neuhaus and S Mitra and S Biswas and A Feinberg and A M Summers and A Nakano and P Vashishta and F Shimojo and J Wu and C C Vera and S A Maier and E Cort\'{e}s and B Bergues and M F Kling},

url = {https://doi.org/10.1126/sciadv.adp1890},

doi = {10.1126/sciadv.adp1890},

year  = {2024},

date = {2024-08-07},

journal = {Science Advances},

volume = {10},

number = {32},

pages = {eadp1890},

abstract = {Surface charges play a fundamental role in physics and chemistry, in particular in shaping the catalytic properties of nanomaterials. However, tracking nanoscale surface charge dynamics remains challenging due to the involved length and time scales. Here, we demonstrate time-resolved access to the nanoscale charge dynamics on dielectric nanoparticles using reaction nanoscopy. We present a four-dimensional visualization of the spatiotemporal evolution of the charge density on individual SiO2 nanoparticles under strong-field irradiation with femtosecond-nanometer resolution. The initially localized surface charges exhibit a biexponential redistribution over time. Our findings reveal the influence of surface charges on surface molecular bonding through quantum dynamical simulations. We performed semi-classical simulations to uncover the roles of diffusion and charge loss in the surface charge redistribution process. Understanding nanoscale surface charge dynamics and its influence on chemical bonding on a single-nanoparticle level unlocks an increased ability to address global needs in renewable energy and advanced health care. Time-resolved visualization of surface charge dynamics on single nanoparticles shows bond-weakening effects for surface molecules.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {High-Power Impulse Magnetron Sputter Deposition of Ag on Self-Assembled Au Nanoparticle Arrays at Low-Temperature Dewetting Conditions},

author = {T Guan and S Liang and Y Kang and E Pensa and D Li and W Liang and Z Liang and Y Bulut and K A Reck and T Xiao and R Guo and J Drewes and T Strunskus and M Schwartzkopf and F Faupel and S V Roth and E Cort\'{e}s and L Jiang and P M\"{u}ller-Buschbaum},

url = {https://doi.org/10.1021/acsami.4c10726},

doi = {10.1021/acsami.4c10726},

issn = {1944-8244},

year  = {2024},

date = {2024-07-31},

journal = {ACS Applied Materials \& Interfaces},

volume = {16},

number = {30},

pages = {40286-40296},

abstract = {Plasmons have facilitated diverse analytical applications due to the boosting signal detectability by hot spots. In practical applications, it is crucial to fabricate straightforward, large-scale, and reproducible plasmonic substrates. Dewetting treatment, via applying direct thermal annealing of metal films, has been used as a straightforward method in the fabrication of such plasmonic nanostructures. However, tailoring the evolution of the dewetting process of metal films poses considerable experimental complexities, mainly due to nanoscale structure formation. Here, we use grazing-incidence small- and wide-angle X-ray scattering for the in situ investigation of the high-power impulse magnetron sputter deposition of Ag on self-assembled Au nanoparticle arrays at low-temperature dewetting conditions. This approach allows us to examine both the direct formation of binary Au/Ag nanostructure and the consequential impact of the dewetting process on the spatial arrangement of the bimetallic nanoparticles. It is observed that the dewetting at 100 °C is sufficient to favor the establishment of a homogenized structural configuration of bimetallic nanostructures, which is beneficial for localized surface plasmon resonances (LSPRs). The fabricated metal nanostructures show potential application for the surface-enhanced Raman scattering (SERS) detection of rhodamine 6G molecules. As SERS platform, bimetallic nanostructures formed with dewetting conditions turn out to be superior to those without dewetting conditions. The method in this work is envisioned as a facile strategy for the fabrication of plasmonic nanostructures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Coupling Nano and Atomic Electric Field Confinement for Robust Alkaline Oxygen Evolution},

author = {Q Wang and Y Gong and X Zi and L Gan and E Pensa and Y Liu and Y Xiao and H Li and K Liu and J Fu and J Liu and A Stefancu and C Cai and S Chen and S Zhang and Y-R Lu and T-S Chan and C Ma and X Cao and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1002/anie.202405438},

doi = {https://doi.org/10.1002/anie.202405438},

issn = {1433-7851},

year  = {2024},

date = {2024-07-08},

journal = {Angewandte Chemie International Edition},

volume = {63},

number = {28},

pages = {e202405438},

abstract = {Abstract The alkaline oxygen evolution reaction (OER) is a promising avenue for producing clean fuels and storing intermittent energy. However, challenges such as excessive OH? consumption and strong adsorption of oxygen-containing intermediates hinder the development of alkaline OER. In this study, we propose a cooperative strategy by leveraging both nano-scale and atomically local electric fields for alkaline OER, demonstrated through the synthesis of Mn single atom doped CoP nanoneedles (Mn SA-CoP NNs). Finite element method simulations and density functional theory calculations predict that the nano-scale local electric field enriches OH? around the catalyst surface, while the atomically local electric field improves *O desorption. Experimental validation using in situ attenuated total reflection infrared and Raman spectroscopy confirms the effectiveness of the nano-scale and atomically electric fields. Mn SA-CoP NNs exhibit an ultra-low overpotential of 189?mV at 10?mA?cm?2 and stable operation over 100?hours at ~100?mA?cm?2 during alkaline OER. This innovative strategy provides new insights for enhancing catalyst performance in energy conversion reactions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electronic excitations at the plasmon\textendashmolecule interface},

author = {A Stefancu and N J Halas and P Nordlander and E Cortes},

url = {https://doi.org/10.1038/s41567-024-02537-6},

doi = {10.1038/s41567-024-02537-6},

issn = {1745-2481},

year  = {2024},

date = {2024-07-01},

journal = {Nature Physics},

volume = {20},

number = {7},

pages = {1065-1077},

abstract = {The recent rise of plasmonic materials for solar-to-chemical energy conversion places a focus on the mechanisms associated with charge and energy flow at the metal\textendashmolecule interface. Understanding the connection between these effects and their roles in the plasmonic excitations of adsorbed molecules has been challenging. In this Review, we strive to provide a general framework\textemdashbased on the concept of electron scattering\textemdashthat encompasses the most important effects at the plasmonic metal\textendashmolecule interface. First we use the model of adsorbate-induced surface resistivity to understand the chemical specificity of the electron scattering process. We then analyse two of the most prominent effects in plasmonics through the lens of the electron scattering model: chemical interface damping and the chemical model of surface-enhanced Raman scattering. We show how most metal\textendashadsorbate charge- or energy-transfer interactions can be mapped into two major classes\textemdashelectron scattering through molecular resonances and direct non-resonant electron scattering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Multiplication of the orbital angular momentum of phonon polaritons via sublinear dispersion},

author = {A Mancini and L Nan and R Bert\'{e} and E Cort\'{e}s and H Ren and S A Maier},

url = {https://doi.org/10.1038/s41566-024-01410-5},

doi = {10.1038/s41566-024-01410-5},

issn = {1749-4893},

year  = {2024},

date = {2024-07-01},

journal = {Nature Photonics},

volume = {18},

number = {7},

pages = {677-684},

abstract = {Optical vortices (OVs) promise to greatly enhance optical information capacity via orbital angular momentum multiplexing. The need for the on-chip integration of orbital angular momentum technologies has prompted research into subwavelength-confined polaritonic OVs. However, the topological order imprinted by the structure used for transduction from free-space beams to surface polaritons is inherently fixed after fabrication. Here we overcome this limitation via dispersion-driven topological charge multiplication. We switch the OV topological charge within a small frequency range (~3%) by leveraging the strong sublinear dispersion of low-loss surface phonon polaritons on silicon carbide membranes. Applying the Huygens principle, we quantitatively evaluate the topological order of experimental OVs detected by near-field imaging. We further explore the deuterogenic effect, which predicts the coexistence of multiple topological charges in higher-order polaritonic OVs. Our work demonstrates a viable method to manipulate the topological charge of polaritonic OVs, paving the way for the exploration of novel orbital-angular-momentum-enabled light\textendashmatter interactions at mid-infrared frequencies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Arsenic Oxidation Kinetics with Plasmonic Nanocatalysts},

author = {B Miralles and M Y Paredes and A V Bragas and G Grinblat and E Cort\'{e}s and A F Scarpettini},

url = {https://doi.org/10.1021/acs.jpcc.4c02905},

doi = {10.1021/acs.jpcc.4c02905},

issn = {1932-7447},

year  = {2024},

date = {2024-06-20},

journal = {The Journal of Physical Chemistry C},

volume = {128},

number = {24},

pages = {10017-10024},

abstract = {Arsenic is one of the most toxic elements present in natural waters, and prolonged ingestion causes severe damage to health. Its oxidation from highly toxic As(III) to less harmful species involving As(V) is a process included in most remediation methods. The kinetics of this homogeneous redox reaction in the presence of hydrogen peroxide is very slow. We propose the use of metal nanoparticles as plasmonic catalysts for this reaction assisted by solar illumination. In this work, we show that As(III) oxidation to As(V) is accelerated by gold and silver nanoparticles through heterogeneous catalysis, and under plasmon excitation, hot charge carriers are generated that contribute to further increase in the reaction rate. We evaluate the efficiency of these nanocatalysts and their dependence on the excitation wavelength, and we quantify the different contributions to the oxidation process. Our results show that gold nanoparticles are better heterogeneous catalysts than silver nanoparticles; however, the latter increase their efficiency 8 times under resonant illumination, with irradiation powers close to that of sunlight, evidencing that the lower-cost material becomes a more efficient catalyst with light.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Si metasurface supporting multiple quasi-BICs for degenerate four-wave mixing},

author = {G Q Moretti and T Weber and T Possmayer and E Cort\'{e}s and L D S Menezes and A V Bragas and S A Maier and A Tittl and G Grinblat},

url = {https://doi.org/10.1515/nanoph-2024-0128},

doi = {doi:10.1515/nanoph-2024-0128},

year  = {2024},

date = {2024-06-05},

journal = {Nanophotonics},

volume = {13},

number = {18},

pages = {3421-3428},

abstract = {Dielectric metasurfaces supporting quasi-bound states in the continuum (qBICs) enable high field enhancement with narrow-linewidth resonances in the visible and near-infrared ranges. The resonance emerges when distorting the meta-atom’s geometry away from a symmetry-protected BIC condition and, usually, a given design can sustain one or two of these states. In this work, we introduce a silicon-on-silica metasurface that simultaneously supports up to four qBIC resonances in the near-infrared region. This is achieved by combining multiple symmetry-breaking distortions on an elliptical cylinder array. By pumping two of these resonances, the nonlinear process of degenerate four-wave mixing is experimentally realized. By comparing the nonlinear response with that of an unpatterned silicon film, the near-field enhancement inside the nanostructured dielectric is revealed. The presented results demonstrate independent geometric control of multiple qBICs and their interaction through wave mixing processes, opening new research pathways in nanophotonics, with potential applications in information multiplexing, multi-wavelength sensing and nonlinear imaging.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Early stages of covalent organic framework formation imaged in operando},

author = {C G Gruber and L Frey and R Guntermann and D D Medina and E Cort\'{e}s},

url = {https://doi.org/10.1038/s41586-024-07483-0},

doi = {10.1038/s41586-024-07483-0},

issn = {1476-4687},

year  = {2024},

date = {2024-06-01},

journal = {Nature},

volume = {630},

number = {8018},

pages = {872-877},

abstract = {Covalent organic frameworks (COFs) are a functional material class able to harness, convert and store energy. However, after almost 20 years of research, there are no coherent prediction rules for their synthesis conditions. This is partly because of an incomplete picture of nucleation and growth at the early stages of formation. Here we use the optical technique interferometric scattering microscopy (iSCAT)1\textendash3 for in operando studies of COF polymerization and framework formation. We observe liquid\textendashliquid phase separation, pointing to the existence of structured solvents in the form of surfactant-free (micro)emulsions in conventional COF synthesis. Our findings show that the role of solvents extends beyond solubility to being kinetic modulators by compartmentation of reactants and catalyst. Taking advantage of these observations, we develop a synthesis protocol for COFs using room temperature instead of elevated temperatures. This work connects framework synthesis with liquid phase diagrams and thereby enables an active design of the reaction environment, emphasizing that visualization of chemical reactions by means of light-scattering-based techniques can be a powerful approach for advancing rational materials synthesis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Focusing Surface Acoustic Waves with a Plasmonic Hypersonic Lens},

author = {H D Boggiano and L Nan and G Grinblat and S A Maier and E Cort\'{e}s and A V Bragas},

url = {https://doi.org/10.1021/acs.nanolett.4c01251},

doi = {10.1021/acs.nanolett.4c01251},

issn = {1530-6984},

year  = {2024},

date = {2024-05-29},

journal = {Nano Letters},

volume = {24},

number = {21},

pages = {6362-6368},

abstract = {Plasmonic nanoantennas have proven to be efficient transducers of electromagnetic to mechanical energy and vice versa. The sudden thermal expansion of these structures after an ultrafast optical pulsed excitation leads to the emission of hypersonic acoustic waves to the supporting substrate, which can be detected by another antenna that acts as a high-sensitivity mechanical probe due to the strong modulation of its optical response. Here, we propose and experimentally demonstrate a nanoscale acoustic lens comprised of 11 gold nanodisks whose collective oscillation at gigahertz frequencies gives rise to an interference pattern that results in a diffraction-limited surface acoustic beam of about 340 nm width, with an amplitude contrast of 60%. Via spatially decoupled pump\textendashprobe experiments, we were able to map the radiated acoustic energy in the proximity of the focal area, obtaining a very good agreement with the continuum elastic theory.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Lattice Oxygen Activation through Deep Oxidation of Co4N by Jahn\textendashTeller\textendashActive Dopants for Improved Electrocatalytic Oxygen Evolution},

author = {J Han and H Wang and Y Wang and H Zhang and J Li and Y Xia and J Zhou and Z Wang and M Luo and Y Wang and N Wang and E Cort\'{e}s and Z Wang and A Vomiero and Z-F Huang and H Ren and X Yuan and S Chen and D Feng and X Sun and Y Liu and H Liang},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202405839},

doi = {https://doi.org/10.1002/anie.202405839},

issn = {1433-7851},

year  = {2024},

date = {2024-05-27},

journal = {Angewandte Chemie International Edition},

volume = {63},

number = {33},

pages = {e202405839},

abstract = {Abstract Triggering the lattice oxygen oxidation mechanism is crucial for improving oxygen evolution reaction (OER) performance, because it could bypass the scaling relation limitation associated with the conventional adsorbate evolution mechanism through the direct formation of oxygen\textendashoxygen bond. High-valence transition metal sites are favorable for activating the lattice oxygen, but the deep oxidation of pre-catalysts suffers from a high thermodynamic barrier. Here, taking advantage of the Jahn\textendashTeller (J\textendashT) distortion induced structural instability, we incorporate high-spin Mn3+ ( t2g3eg1 $t_2g^3e_g^1$ ) dopant into Co4N. Mn dopants enable a surface structural transformation from Co4N to CoOOH, and finally to CoO2, as observed by various in situ spectroscopic investigations. Furthermore, the reconstructed surface on Mn-doped Co4N triggers the lattice oxygen activation, as evidenced experimentally by pH-dependent OER, tetramethylammonium cation adsorption and online electrochemical mass spectrometry measurements of 18O-labelled catalysts. In general, this work not only offers the introducing J\textendashT effect approach to regulate the structural transition, but also provides an understanding about the influence of the catalyst's electronic configuration on determining the reaction route, which may inspire the design of more efficient catalysts with activated lattice oxygen.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Effect of crystal facets in plasmonic catalysis},

author = {Y Kang and S M Jo\~{a}o and R Lin and K Liu and L Zhu and J Fu and W M Cheong and S Lee and K Frank and B Nickel and M Liu and J Lischner and E Cort\'{e}s},

doi = {10.1038/s41467-024-47994-y},

issn = {2041-1723},

year  = {2024},

date = {2024-05-09},

journal = {Nat Commun},

volume = {15},

number = {1},

pages = {3923},

abstract = {While the role of crystal facets is well known in traditional heterogeneous catalysis, this effect has not yet been thoroughly studied in plasmon-assisted catalysis, where attention has primarily focused on plasmon-derived mechanisms. Here, we investigate plasmon-assisted electrocatalytic CO(2) reduction using different shapes of plasmonic Au nanoparticles - nanocube (NC), rhombic dodecahedron (RD), and octahedron (OC) - exposing 100, 110, and 111 facets, respectively. Upon plasmon excitation, Au OCs doubled CO Faradaic efficiency (FE(CO)) and tripled CO partial current density (j(CO)) compared to a dark condition, with NCs also improving under illumination. In contrast, Au RDs maintained consistent performance irrespective of light exposure, suggesting minimal influence of light on the reaction. Temperature experiments ruled out heat as the main factor to explain such differences. Atomistic simulations and electromagnetic modeling revealed higher hot carrier abundance and electric field enhancement on Au OCs and NCs than RDs. These effects now dominate the reaction landscape over the crystal facets, thus shifting the reaction sites when comparing dark and plasmon-activated processes. Plasmon-assisted H(2) evolution reaction experiments also support these findings. The dominance of low-coordinated sites over facets in plasmonic catalysis suggests key insights for designing efficient photocatalysts for energy conversion and carbon neutralization.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Highly confined incident-angle-robust surface phonon polariton bound states in the continuum metasurfaces},

author = {L Nan and A Mancini and T Weber and G L Seah and E Cort\'{e}s and A Tittl and S A Maier},

year  = {2024},

date = {2024-03-27},

journal = {arXiv preprint arXiv:2403.18743},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Surface-Enhanced Raman Scattering in BIC-Driven Semiconductor Metasurfaces},

author = {H Hu and A K Pal and A Berestennikov and T Weber and A Stefancu and E Cort\'{e}s and S A Maier and A Tittl},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202302812},

doi = {https://doi.org/10.1002/adom.202302812},

issn = {2195-1071},

year  = {2024},

date = {2024-02-05},

journal = {Advanced Optical Materials},

volume = {12},

number = {14},

pages = {2302812},

abstract = {Abstract Semiconductor-based surface-enhanced Raman spectroscopy (SERS) substrates, as a new frontier in the field of SERS, are hindered by their poor electromagnetic field confinement and weak light-matter interaction. Metasurfaces, a class of 2D artificial materials based on the electromagnetic design of nanophotonic resonators, enable strong electromagnetic field enhancement and optical absorption engineering for a wide range of semiconductors. However, the engineering of semiconductor substrates into metasurfaces for improving SERS activity remains underexplored. Here, an improved SERS metasurface platform is developed that leverages the combination of titanium oxide (TiO2) and the emerging physical concept of optical bound states in the continuum (BICs) to boost the Raman emission. Moreover, fine-tuning of BIC-assisted resonant absorption offers a pathway for maximizing the photoinduced charge transfer effect (PICT) in SERS. High values of BIC-assisted electric field enhancement (|E/E0|2 ≈103) are achieved, challenging the preconception of weak electromagnetic (EM) field enhancement on semiconductor SERS substrates. The BIC-assisted TiO2 metasurface platform offers a new dimension in spectrally-tunable SERS with earth-abundant and bio-compatible semiconductor materials, beyond the traditional plasmonic ones.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Unraveling the Chirality Transfer from Circularly Polarized Light to Single Plasmonic Nanoparticles},

author = {S Lee and C Fan and A Movsesyan and J B\"{u}rger and F J Wendisch and L De S. Menezes and S A Maier and H Ren and T Liedl and L V Besteiro and A O Govorov and E Cort\'{e}s},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202319920},

doi = {https://doi.org/10.1002/anie.202319920},

issn = {1433-7851},

year  = {2024},

date = {2024-01-18},

journal = {Angewandte Chemie International Edition},

volume = {63},

number = {11},

pages = {e202319920},

abstract = {Abstract Due to their broken symmetry, chiral plasmonic nanostructures have unique optical properties and numerous applications. However, there is still a lack of comprehension regarding how chirality transfer occurs between circularly polarized light (CPL) and these structures. Here, we thoroughly investigate the plasmon-assisted growth of chiral nanoparticles from achiral Au nanocubes (AuNCs) via CPL without the involvement of any chiral molecule stimulators. We identify the structural chirality of our synthesized chiral plasmonic nanostructures using circular differential scattering (CDS) spectroscopy, which is correlated with scanning electron microscopy imaging at both the single-particle and ensemble levels. Theoretical simulations, including hot-electron surface maps, reveal that the plasmon-induced chirality transfer is mediated by the asymmetric distribution of hot electrons on achiral AuNCs under CPL excitation. Furthermore, we shed light on how this plasmon-induced chirality transfer can also be utilized for chiral growth in bimetallic systems, such as Ag or Pd on AuNCs. The results presented here uncover fundamental aspects of chiral light-matter interaction and have implications for the future design and optimization of chiral sensors and chiral catalysis, among others.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Unraveling the Chirality Transfer from Circularly Polarized Light to Single Plasmonic Nanoparticles},

author = {S Lee and C Fan and A Movsesyan and J B\"{u}rger and F J Wendisch and L De S. Menezes and S A Maier and H Ren and T Liedl and L V Besteiro and A O Govorov and E Cort\'{e}s},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202319920},

doi = {https://doi.org/10.1002/anie.202319920},

issn = {1433-7851},

year  = {2024},

date = {2024-01-18},

journal = {Angewandte Chemie International Edition},

volume = {63},

number = {11},

pages = {e202319920},

abstract = {Abstract Due to their broken symmetry, chiral plasmonic nanostructures have unique optical properties and numerous applications. However, there is still a lack of comprehension regarding how chirality transfer occurs between circularly polarized light (CPL) and these structures. Here, we thoroughly investigate the plasmon-assisted growth of chiral nanoparticles from achiral Au nanocubes (AuNCs) via CPL without the involvement of any chiral molecule stimulators. We identify the structural chirality of our synthesized chiral plasmonic nanostructures using circular differential scattering (CDS) spectroscopy, which is correlated with scanning electron microscopy imaging at both the single-particle and ensemble levels. Theoretical simulations, including hot-electron surface maps, reveal that the plasmon-induced chirality transfer is mediated by the asymmetric distribution of hot electrons on achiral AuNCs under CPL excitation. Furthermore, we shed light on how this plasmon-induced chirality transfer can also be utilized for chiral growth in bimetallic systems, such as Ag or Pd on AuNCs. The results presented here uncover fundamental aspects of chiral light-matter interaction and have implications for the future design and optimization of chiral sensors and chiral catalysis, among others.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Potential Alignment in Tandem Catalysts Enhances CO2-to-C2H4 Conversion Efficiencies},

author = {M Liu and Q Wang and T Luo and M Herran and X Cao and W Liao and L Zhu and H Li and A Stefancu and Y-R Lu and T-S Chan and E Pensa and C Ma and S Zhang and R Xiao and E Cort\'{e}s},

url = {https://doi.org/10.1021/jacs.3c09632},

doi = {10.1021/jacs.3c09632},

issn = {0002-7863},

year  = {2024},

date = {2024-01-10},

journal = {Journal of the American Chemical Society},

volume = {146},

number = {1},

pages = {468-475},

abstract = {The in-tandem catalyst holds great promise for addressing the limitation of low *CO coverage on Cu-based materials for selective C2H4 generation during CO2 electroreduction. However, the potential mismatch between the CO-formation catalyst and the favorable C\textendashC coupling Cu catalyst represents a bottleneck in these types of electrocatalysts, resulting in low tandem efficiencies. In this study, we propose a robust solution to this problem by introducing a wide-CO generation-potential window nickel single atom catalyst (Ni SAC) supported on a Cu catalyst. The selection of Ni SAC was based on theoretical calculations, and its excellent performance was further confirmed by using in situ IR spectroscopy. The facilitated carbon dimerization in our tandem catalyst led to a ∼370 mA/cm2 partial current density of C2H4, corresponding to a faradic efficiency of ∼62%. This performance remained stable and consistent for at least ∼14 h at a high current density of 500 mA/cm2 in a flow-cell reactor, outperforming most tandem catalysts reported so far.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Efficient method of arsenic removal from water based on photocatalytic oxidation by a plasmonic\textendashmagnetic nanosystem},

author = {M Y Paredes and L P Martinez and B C Barja and M C Marchi and M Herran and G Grinblat and A V Bragas and E Cort\'{e}s and A F Scarpettini},

url = {http://dx.doi.org/10.1039/D2EN01082H},

doi = {10.1039/D2EN01082H},

issn = {2051-8153},

year  = {2023},

date = {2023-12-13},

journal = {Environmental Science: Nano},

volume = {10},

number = {1},

pages = {166-177},

abstract = {Arsenic is one of the most toxic elements in natural waters since prolonged exposure to this metalloid can cause chronic damage to health. Its removal from groundwater remains one of the greatest environmental challenges to be addressed nowadays. Here, we present core\textendashsatellite hybrid nanostructures formed by plasmonic gold satellites supported onto magnetic iron oxide cores for sunlight-driven remediation of arsenic-containing water. Our experimental results show that the gold nanoparticles catalyze the oxidation of arsenic to much less toxic species and that \textendash upon illumination \textendash the generated heat and hot carriers further enhance the reaction rate. The iron oxides act as an arsenic adsorbent, enabling the complete removal of the catalysts and the adsorbed oxidized arsenic species through a magnet. We quantified the different catalytic contributions, showing that the plasmonic one is of the same order as the surface one. This work highlights the synergy between plasmonic catalysts and iron oxides for light-assisted water remediation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Plasmonic bimetallic two-dimensional supercrystals for H2 generation},

author = {M Herran and S Juergensen and M Kessens and D Hoeing and A K\"{o}ppen and A Sousa-Castillo and W J Parak and H Lange and S Reich and F Schulz and E Cort\'{e}s},

url = {https://doi.org/10.1038/s41929-023-01053-9},

doi = {10.1038/s41929-023-01053-9},

issn = {2520-1158},

year  = {2023},

date = {2023-12-01},

journal = {Nature Catalysis},

volume = {6},

issue = {12},

pages = {1205-1214},

abstract = {Sunlight-driven H2 generation is a central technology to tackle our impending carbon-based energy collapse. Colloidal photocatalysts consisting of plasmonic and catalytic nanoparticles are promising for H2 production at solar irradiances, but their performance is hindered by absorption and multiscattering events. Here we present a two-dimensional bimetallic catalyst by incorporating platinum nanoparticles into a well-defined supercrystal of gold nanoparticles. The bimetallic supercrystal exhibited an H2 generation rate of $$139,mathrmmmol,mathrmg_mathrmcat^-1,mathrmh^-1$$via formic acid dehydrogenation under visible light illumination and solar irradiance. This configuration makes it possible to study the interaction between the two metallic materials and the influence of this in catalysis. We observe a correlation between the intensity of the electric field in the hotspots and the boosted catalytic activity of platinum nanoparticles, while identifying a minor role of heat and gold-to-platinum charge transfer in the enhancement. Our results demonstrate the benefits of two-dimensional configurations with optimized architecture for liquid-phase photocatalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Spatial Distributions of Single-Molecule Reactivity in Plasmonic Catalysis},

author = {S Ezendam and J Gargiulo and A Sousa-Castillo and J B Lee and Y S Nam and S A Maier and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsnano.3c07833},

doi = {10.1021/acsnano.3c07833},

issn = {1936-0851},

year  = {2023},

date = {2023-11-16},

journal = {ACS Nano},

abstract = {Plasmonic catalysts have the potential to accelerate and control chemical reactions with light by exploiting localized surface plasmon resonances. However, the mechanisms governing plasmonic catalysis are not simple to decouple. Several plasmon-derived phenomena, such as electromagnetic field enhancements, temperature, or the generation of charge carriers, can affect the reactivity of the system. These effects are convoluted with the inherent (nonplasmonic) catalytic properties of the metal surface. Disentangling these coexisting effects is challenging but is the key to rationally controlling reaction pathways and enhancing reaction rates. This study utilizes super-resolution fluorescence microscopy to examine the mechanisms of plasmonic catalysis at the single-particle level. The reduction reaction of resazurin to resorufin in the presence of Au nanorods coated with a porous silica shell is investigated in situ. This allows the determination of reaction rates with a single-molecule sensitivity and subparticle resolution. By variation of the irradiation wavelength, it is possible to examine two different regimes: photoexcitation of the reactant molecules and photoexcitation of the nanoparticle’s plasmon resonance. In addition, the measured spatial distribution of reactivity allows differentiation between superficial and far-field effects. Our results indicate that the reduction of resazurin can occur through more than one reaction pathway, being most efficient when the reactant is photoexcited and is in contact with the Au surface. In addition, it was found that the spatial distribution of enhancements varies, depending on the underlying mechanism. These findings contribute to the fundamental understanding of plasmonic catalysis and the rational design of future plasmonic nanocatalysts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optical Readout of the Mechanical Properties of Silica Mesoporous Thin Films Using Plasmonic Nanoantennas},

author = {H D Boggiano and J I Ramallo and L Nan and A Litwiller and E Cort\'{e}s and S A Maier and G Grinblat and M C Fuertes and P C Angelom\'{e} and A V Bragas},

url = {https://doi.org/10.1021/acsphotonics.3c00874},

doi = {10.1021/acsphotonics.3c00874},

year  = {2023},

date = {2023-11-15},

journal = {ACS Photonics},

volume = {10},

number = {11},

pages = {3998-4005},

abstract = {In this work, we apply the recently developed frequency shift of nanoantennas (FRESA) technique to measure the Young’s modulus of thin mesoporous films at GHz frequencies as a function of porosity with local precision. The method measures changes in the mechanical oscillation frequency of optically excited plasmonic nanoantennas with modification of their surrounding medium. The values obtained range from 4 to 10 GPa for porosities extending from 35 to 4%, compatible with reports on films grown under similar conditions. We further find comparable results when using the well-established nanoindentation (NI) technique, validating the new method. By analysis of the nanoresonator’s quality factor, the measurement reveals an excellent interfacial adhesion of the films to the nanoantennas. Different from most other characterization techniques, FRESA provides elastic modulus determination at GHz frequencies, relevant for the operation of current devices. Furthermore, FRESA exhibits, in principle, no limitations in terms of film thickness, in contrast to the NI, which is strongly affected by the stiffness of the substrate for ultrathin films.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Semiconductor Metasurfaces for Surface-enhanced Raman Scattering},

author = {H Hu and A K Pal and A Berestennikov and T Weber and A Stefancu and E Cortes and S A Maier and A Tittl},

url = {https://arxiv.org/abs/2309.10732},

doi = {https://doi.org/10.48550/arXiv.2309.10732},

year  = {2023},

date = {2023-09-19},

journal = {arXiv preprint arXiv:2309.10732},

abstract = {Semiconductor-based surface-enhanced Raman spectroscopy (SERS) substrates, as a new frontier in the field of SERS, are hindered by their poor electromagnetic field confinement, and weak light-matter interaction. Metasurfaces, a class of 2D artificial materials based on the electromagnetic design of nanophotonic resonators, enable strong electromagnetic field enhancement and optical absorption engineering for a wide range of semiconductor materials. However, the engineering of semiconductor substrates into metasurfaces for improving SERS activity remains underexplored. Here, we develop an improved SERS metasurface platform that leverages the combination of titanium oxide (TiO2) and the emerging physical concept of optical bound states in the continuum (BICs) to boost the Raman emission. Moreover, fine-tuning of BIC-assisted resonant absorption offers a pathway for maximizing the photoinduced charge transfer effect (PICT) in SERS. We achieve ultrahigh values of BIC-assisted electric field enhancement (|E/E0|^2 ~ 10^3), challenging the preconception of weak electromagnetic (EM) field enhancement on semiconductor SERS substrates. Our BIC-assisted TiO2 metasurface platform offers a new dimension in spectrally-tunable SERS with earth-abundant and bio-compatible semiconductor materials, beyond the traditional plasmonic ones.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Theory of Hot-Carrier Generation in Bimetallic Plasmonic Catalysts},

author = {H Jin and M Herran and E Cort\'{e}s and J Lischner},

url = {https://doi.org/10.1021/acsphotonics.3c00715},

doi = {10.1021/acsphotonics.3c00715},

year  = {2023},

date = {2023-09-15},

urldate = {2023-09-25},

journal = {ACS Photonics},

volume = {10},

number = {10},

pages = {3629-3636},

abstract = {Bimetallic nanoreactors in which a plasmonic metal is used to funnel solar energy toward a catalytic metal have recently been studied experimentally, but a detailed theoretical understanding of these systems is lacking. Here, we present theoretical results of hot-carrier generation rates of different Au\textendashPd nanoarchitectures. In particular, we study spherical core\textendashshell nanoparticles with a Au core and a Pd shell as well as antenna\textendashreactor systems consisting of a large Au nanoparticle that acts as an antenna and a smaller Pd satellite nanoparticle separated by a gap. In addition, we investigate an antenna\textendashreactor system in which the satellite is a core\textendashshell nanoparticle. Hot-carrier generation rates are obtained from an atomistic quantum-mechanical modeling technique which combines a solution of Maxwell’s equation with a tight-binding description of the nanoparticle electronic structure. We find that antenna\textendashreactor systems exhibit significantly higher hot-carrier generation rates in the catalytic material than the core\textendashshell system as a result of strong electric field enhancements associated with the gap between the antenna and the satellite. For these systems, we also study the dependence of the hot-carrier generation rate on the size of the gap, the radius of the antenna nanoparticle, and the direction of light polarization. Overall, we find a strong correlation between the calculated hot-carrier generation rates and the experimentally measured chemical activity for the different Au\textendashPd photocatalysts. Our insights pave the way toward a microscopic understanding of hot-carrier generation in heterogeneous nanostructures for photocatalysis and other energy-conversion applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Anti Stokes Thermometry of Plasmonic Nanoparticle Arrays},

author = {S Ezendam and L Nan and I L Violi and S A Maier and E Cort\'{e}s and G Baffou and J Gargiulo},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202301496},

doi = {https://doi.org/10.1002/adom.202301496},

issn = {2195-1071},

year  = {2023},

date = {2023-09-14},

journal = {Advanced Optical Materials},

volume = {n/a},

number = {n/a},

pages = {2301496},

abstract = {Abstract Metallic nanoparticles possess strong photothermal responses, especially when illuminated as ensembles due to collective effects. However, accurately quantifying the temperature increase remains a significant challenge, impeding progress in several applications. Anti Stokes thermometry offers a promising solution by enabling direct and non-invasive temperature measurements of the metal without the need for labeling or prior calibration. While Anti Stokes thermometry is successfully applied to individual nanoparticles, its potential to study light-to-heat conversion with plasmonic ensembles remains unexplored. In this study, the theoretical framework and the conditions that must be fulfilled for applying Anti Stokes thermometry to ensembles of nanoparticles are discussed. Then, this technique is implemented to measure the light-induced heating of square arrays of Au nanodisks. The obtained temperature measurements are validated using wavefront microscopy, demonstrating excellent agreement between the two thermometry methods. These results showcase the extension of Anti Stokes thermometry to plasmonic ensembles, highlighting its potential for implementation in the diverse photothermal applications involving these systems.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Photo-induced enhanced Raman spectroscopy as a probe for photocatalytic surfaces},

author = {S Ben-Jaber and D Glass and T Brick and S A Maier and I P Parkin and E Cort\'{e}s and W J Peveler and R Quesada-Cabrera},

url = {https://royalsocietypublishing.org/doi/abs/10.1098/rsta.2022.0343},

doi = {doi:10.1098/rsta.2022.0343},

year  = {2023},

date = {2023-09-11},

journal = {Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences},

volume = {381},

number = {2259},

pages = {20220343},

abstract = {Photo-induced enhanced Raman spectroscopy (PIERS) has emerged as a highly sensitive surface-enhanced Raman spectroscopy (SERS) technique for the detection of ultra-low concentrations of organic molecules. The PIERS mechanism has been largely attributed to UV-induced formation of surface oxygen vacancies (Vo) in semiconductor materials, although alternative interpretations have been suggested. Very recently, PIERS has been proposed as a surface probe for photocatalytic materials, following Vo formation and healing kinetics. This work establishes comparison between PIERS and Vo-induced SERS approaches in defected noble-metal-free titanium dioxide (TiO2-x) films to further confirm the role of Vo in PIERS. Upon application of three post-treatment methods (namely UV-induction, vacuum annealing and argon etching), correlation of Vo kinetics and distribution could be established. A proposed mechanism and further discussion on PIERS as a probe to explore photocatalytic materials are also presented. This article is part of the theme issue ‘Exploring the length scales, timescales and chemistry of challenging materials (Part 2)’.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Breaking K+ Concentration Limit on Cu Nanoneedles for Acidic Electrocatalytic CO2 Reduction to Multi-Carbon Products},

author = {X Zi and Y Zhou and L Zhu and Q Chen and Y Tan and X Wang and M Sayed and E Pensa and R A Geioushy and K Liu and J Fu and E Cort\'{e}s and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202309351},

doi = {https://doi.org/10.1002/anie.202309351},

issn = {1433-7851},

year  = {2023},

date = {2023-08-28},

journal = {Angewandte Chemie International Edition},

volume = {62},

number = {42},

pages = {e202309351},

abstract = {Abstract Electrocatalytic CO2 reduction reaction (CO2RR) to multi-carbon products (C2+) in acidic electrolyte is one of the most advanced routes for tackling our current climate and energy crisis. However, the competing hydrogen evolution reaction (HER) and the poor selectivity towards the valuable C2+ products are the major obstacles for the upscaling of these technologies. High local potassium ions (K+) concentration at the cathode's surface can inhibit proton-diffusion and accelerate the desirable carbon-carbon (C−C) coupling process. However, the solubility limit of potassium salts in bulk solution constrains the maximum achievable K+ concentration at the reaction sites and thus the overall acidic CO2RR performance of most electrocatalysts. In this work, we demonstrate that Cu nanoneedles induce ultrahigh local K+ concentrations (4.22 M) \textendash thus breaking the K+ solubility limit (3.5 M) \textendash which enables a highly efficient CO2RR in 3 M KCl at pH=1. As a result, a Faradaic efficiency of 90.69±2.15 % for C2+ (FEC2+) can be achieved at 1400 mA.cm−2, simultaneous with a single pass carbon efficiency (SPCE) of 25.49±0.82 % at a CO2 flow rate of 7 sccm.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Highly Efficient Decomposition of Perfluorocarbons for over 1000 Hours via Active Site Regeneration},

author = {H Zhang and T Luo and Y Chen and K Liu and H Li and E Pensa and J Fu and Z Lin and L Chai and E Cort\'{e}s and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202305651},

doi = {https://doi.org/10.1002/anie.202305651},

issn = {1433-7851},

year  = {2023},

date = {2023-08-23},

journal = {Angewandte Chemie International Edition},

volume = {62},

number = {46},

pages = {e202305651},

abstract = {Abstract Tetrafluoromethane (CF4), the simplest perfluorocarbon (PFC), has the potential to exacerbate global warming. Catalytic hydrolysis is a viable method to degrade CF4, but fluorine poisoning severely restricts both the catalytic performance and catalyst lifetime. In this study, Ga is introduced to effectively assists the defluorination of poisoned Al active sites, leading to highly efficient CF4 decomposition at 600 °C with a catalytic lifetime exceeding 1,000 hours. 27Al and 71Ga magic-angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) showed that the introduced Ga exists as tetracoordinated Ga sites (GaIV), which readily dissociate water to form Ga−OH. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density function theory (DFT) calculations confirmed that Ga−OH assists the defluorination of poisoned Al active sites via a dehydration-like process. As a result, the Ga/Al2O3 catalyst achieved 100 % CF4 decomposition keeping an ultra-long catalytic lifetime and outperforming reported results. This work proposes a new approach for efficient and long-term CF4 decomposition by promoting the regeneration of active sites.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optimization of p-Type Cu2O Nanocube Photocatalysts Based on Electronic Effects},

author = {R Lin and H Chen and T Cui and Z Zhang and Q Zhou and L Nan and W-C Cheong and L Schr\"{o}ck and V Ramm and Q Ding and X Liang and S Saris and F J Wendisch and S A Maier and R A Fischer and Y Zhu and D Wang and E Cortes},

url = {https://doi.org/10.1021/acscatal.3c02710},

doi = {10.1021/acscatal.3c02710},

year  = {2023},

date = {2023-08-14},

journal = {ACS Catalysis},

pages = {11352-11361},

abstract = {The size effect in semiconductor photocatalysis has been widely investigated but still remains elusive. Herein, employing p-type Cu2O nanocubes as the heterogeneous photocatalysts, we propose a feasible size optimization strategy to enhance the photocatalytic performance of semiconductors. With the size of Cu2O increasing from 2.5 nm (exciton Bohr radius) to 5 nm (twice the exciton Bohr radius), the corresponding calculated band gap of Cu2O decreases from 3.39 to 2.41 eV, indicating that controlling the size to above twice the exciton Bohr radius is vital for retaining the visible-light response of Cu2O. Based on the theoretical calculations and experimental measurements of the charge carrier dynamics, we found that the synthesized 30 nm Cu2O nanocubes have an electron diffusion length of 191 nm, while 229 nm Cu2O nanocubes show an electron diffusion length of 45 nm. An electron diffusion length larger than the semiconductor particle size lowers the electron\textendashhole recombination, resulting in a visible-light CO generation rate 23.4 times higher for the smaller Cu2O nanocubes than that for the larger ones. These results verify that confining Cu2O size to within the minority carrier diffusion length and above twice the exciton Bohr radius is a promising way to enhance Cu2O photocatalytic activity.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optimizing Hot Electron Harvesting at Planar Metal\textendashSemiconductor Interfaces with Titanium Oxynitride Thin Films},

author = {B Doiron and Y Li and R Bower and A Mihai and S Dal Forno and S Fearn and L H\"{u}ttenhofer and E Cort\'{e}s and L F Cohen and N M Alford and J Lischner and P Petrov and S A Maier and R F Oulton},

url = {https://doi.org/10.1021/acsami.3c02812},

doi = {10.1021/acsami.3c02812},

issn = {1944-8244},

year  = {2023},

date = {2023-06-28},

journal = {ACS Applied Materials \& Interfaces},

volume = {15},

number = {25},

pages = {30417-30426},

abstract = {Understanding metal\textendashsemiconductor interfaces is critical to the advancement of photocatalysis and sub-bandgap solar energy harvesting where electrons in the metal can be excited by sub-bandgap photons and extracted into the semiconductor. In this work, we compare the electron extraction efficiency across Au/TiO2 and titanium oxynitride (TiON)/TiO2\textendashx interfaces, where in the latter case the spontaneously forming oxide layer (TiO2\textendashx) creates a metal\textendashsemiconductor contact. Time-resolved pump\textendashprobe spectroscopy is used to study the electron recombination rates in both cases. Unlike the nanosecond recombination lifetimes in Au/TiO2, we find a bottleneck in the electron relaxation in the TiON system, which we explain using a trap-mediated recombination model. Using this model, we investigate the tunability of the relaxation dynamics with oxygen content in the parent film. The optimized film (TiO0.5N0.5) exhibits the highest carrier extraction efficiency (NFC ≈ 2.8 × 1019 m\textendash3), slowest trapping, and an appreciable hot electron population reaching the surface oxide (NHE ≈ 1.6 × 1018 m\textendash3). Our results demonstrate the productive role oxygen can play in enhancing electron harvesting and prolonging electron lifetimes, providing an optimized metal\textendashsemiconductor interface using only the native oxide of titanium oxynitride.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Impact of bimetallic interface design on heat generation in plasmonic Au/Pd nanostructures studied by single-particle thermometry},

author = {J Gargiulo and M Herran and I L Violi and A Sousa-Castillo and L P Martinez and S Ezendam and M Barella and H Giesler and R Grzeschik and S Schl\"{u}cker and S A Maier and F D Stefani and E Cort\'{e}s},

url = {https://doi.org/10.1038/s41467-023-38982-9},

doi = {10.1038/s41467-023-38982-9},

issn = {2041-1723},

year  = {2023},

date = {2023-06-27},

journal = {Nature Communications},

volume = {14},

number = {1},

pages = {3813},

abstract = {Localized surface plasmons are lossy and generate heat. However, accurate measurement of the temperature of metallic nanoparticles under illumination remains an open challenge, creating difficulties in the interpretation of results across plasmonic applications. Particularly, there is a quest for understanding the role of temperature in plasmon-assisted catalysis. Bimetallic nanoparticles combining plasmonic with catalytic metals are raising increasing interest in artificial photosynthesis and the production of solar fuels. Here, we perform single-particle thermometry measurements to investigate the link between morphology and light-to-heat conversion of colloidal Au/Pd nanoparticles with two different configurations: core\textendashshell and core-satellite. It is observed that the inclusion of Pd as a shell strongly reduces the photothermal response in comparison to the bare cores, while the inclusion of Pd as satellites keeps photothermal properties almost unaffected. These results contribute to a better understanding of energy conversion processes in plasmon-assisted catalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Direct Bottom-Up In Situ Growth: A Paradigm Shift for Studies in Wet-Chemical Synthesis of Gold Nanoparticles},

author = {G A Vinnacombe-Willson and Y Conti and A Stefancu and P S Weiss and E Cort\'{e}s and L Scarabelli},

url = {https://doi.org/10.1021/acs.chemrev.2c00914},

doi = {10.1021/acs.chemrev.2c00914},

issn = {0009-2665},

year  = {2023},

date = {2023-06-06},

journal = {Chemical Reviews},

volume = {123},

number = {13},

pages = {8488-8529},

abstract = {Plasmonic gold nanoparticles have been used increasingly in solid-state systems because of their applicability in fabricating novel sensors, heterogeneous catalysts, metamaterials, and thermoplasmonic substrates. While bottom-up colloidal syntheses take advantage of the chemical environment to control size, shape, composition, surface chemistry, and crystallography of the nanostructures precisely, it can be challenging to assemble nanoparticles rationally from suspension onto solid supports or within devices. In this Review, we discuss a powerful recent synthetic methodology, bottom-up in situ substrate growth, which circumvents time-consuming batch presynthesis, ligand exchange, and self-assembly steps by applying wet-chemical synthesis to form morphologically controlled nanostructures on supporting materials. First, we briefly introduce the properties of plasmonic nanostructures. Then we comprehensively summarize recent work that adds to the synthetic understanding of in situ geometrical and spatial control (patterning). Next, we briefly discuss applications of plasmonic hybrid materials prepared by in situ growth. Overall, despite the vast potential advantages of in situ growth, the mechanistic understanding of these methodologies remains far from established, providing opportunities and challenges for future research.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Asymmetric Coordination Induces Electron Localization at Ca Sites for Robust CO2 Electroreduction to CO},

author = {Q Wang and M Dai and H Li and Y-R Lu and T-S Chan and C Ma and K Liu and J Fu and W Liao and S Chen and E Pensa and Y Wang and S Zhang and Y Sun and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1002/adma.202300695},

doi = {https://doi.org/10.1002/adma.202300695},

issn = {0935-9648},

year  = {2023},

date = {2023-05-01},

journal = {Advanced Materials},

volume = {35},

number = {21},

pages = {2300695},

abstract = {Abstract Main group single atom catalysts (SACs) are promising for CO2 electroreduction to CO by virtue of their ability in preventing the hydrogen evolution reaction and CO poisoning. Unfortunately, their delocalized orbitals reduce the CO2 activation to *COOH. Herein, an O doping strategy to localize electrons on p-orbitals through asymmetric coordination of Ca SAC sites (Ca-N3O) is developed, thus enhancing the CO2 activation. Theoretical calculations indicate that asymmetric coordination of Ca-N3O improves electron-localization around Ca sites and thus promotes *COOH formation. X-ray absorption fine spectroscopy shows the obtained Ca-N3O features: one O and three N coordinated atoms with one Ca as a reactive site. In situ attenuated total reflection infrared spectroscopy proves that Ca-N3O promotes *COOH formation. As a result, the Ca-N3O catalyst exhibits a state-of-the-art turnover frequency of ≈15 000 per hour in an H-cell and a large current density of ?400 mA cm?2 with a CO Faradaic efficiency (FE) ≥ 90% in a flow cell. Moreover, Ca-N3O sites retain a FE above 90% even with a 30% diluted CO2 concentration.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Potential-Dependent Active Moiety of Fe\textendashN\textendashC Catalysts for the Oxygen Reduction Reaction},

author = {K Liu and J Fu and T Luo and G Ni and H Li and L Zhu and Y Wang and Z Lin and Y Sun and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1021/acs.jpclett.3c00583},

doi = {10.1021/acs.jpclett.3c00583},

year  = {2023},

date = {2023-04-20},

journal = {The Journal of Physical Chemistry Letters},

volume = {14},

number = {15},

pages = {3749-3756},

abstract = {The real active moiety of Fe\textendashN\textendashC single-atom catalysts (SACs) during the oxygen reduction reaction (ORR) depends on the applied potential. Here, we examine the ORR activity of various SAC active moieties (Fe\textendashN4, Fe\textendash(OH)N4, Fe\textendash(O2)N4, and Fe\textendash(OH2)N4) over a wide potential window ranging from −0.8 to 1.0 V (vs. SHE) using constant potential density functional theory calculations. We show that the ORR activity of the Fe\textendashN4 moiety is hindered by the slow *OH protonation, while the Fe\textendash(OH2)N4 (0.4 V ≤ U ≤ 1.0 V), *O2-assisted Fe\textendashN4 (−0.6 V ≤ U ≤ 0.2 V), and Fe\textendash(OH)N4 (U = −0.8 V) moieties dominate the ORR activity of the Fe\textendashN\textendashC catalysts at different potential windows. These oxygenated species modified the single-atom Fe sites and can promote *OH protonation by regulating the electron occupancy of the Fe 3dz2 (spin-up) and Fe 3dxz (spin-down) orbitals. Overall, our findings provide guidance for understanding the active moieties of SACs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Investigating Plasmonic Catalysis Kinetics on Hot-Spot Engineered Nanoantennae},

author = {L Nan and J Gir\'{a}ldez-Mart\'{i}nez and A Stefancu and L Zhu and M Liu and A O Govorov and L V Besteiro and E Cort\'{e}s},

url = {https://doi.org/10.1021/acs.nanolett.3c00219},

doi = {10.1021/acs.nanolett.3c00219},

issn = {1530-6984},

year  = {2023},

date = {2023-03-31},

journal = {Nano Letters},

abstract = {Strong hot-spots can facilitate photocatalytic reactions potentially providing effective solar-to-chemical energy conversion pathways. Although it is well-known that the local electromagnetic field in plasmonic nanocavities increases as the cavity size reduces, the influence of hot-spots on photocatalytic reactions remains elusive. Herein, we explored hot-spot dependent catalytic behaviors on a highly controlled platform with varying interparticle distances. Plasmon-meditated dehalogenation of 4-iodothiophenol was employed to observe time-resolved catalytic behaviors via in situ surface-enhanced Raman spectroscopy on dimers with 5, 10, 20, and 30 nm interparticle distances. As a result, we show that by reducing the gap from 20 to 10 nm, the reaction rate can be sped up more than 2 times. Further reduction in the interparticle distance did not improve reaction rate significantly although the maximum local-field was ∼2.3-fold stronger. Our combined experimental and theoretical study provides valuable insights in designing novel plasmonic photocatalytic platforms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Improved In Situ Characterization of Electrochemical Interfaces Using Metasurface-Driven Surface-Enhanced IR Absorption Spectroscopy},

author = {L M Berger and M Duportal and L D S Menezes and E Cort\'{e}s and S A Maier and A Tittl and K Krischer},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202300411},

doi = {https://doi.org/10.1002/adfm.202300411},

issn = {1616-301X},

year  = {2023},

date = {2023-03-20},

urldate = {2023-03-20},

journal = {Advanced Functional Materials},

volume = {33},

issue = {25},

pages = {2300411},

abstract = {Abstract Electrocatalysis plays a crucial role in realizing the transition toward a zero-carbon future, driving research directions from green hydrogen generation to carbon dioxide reduction. Surface-enhanced infrared absorption spectroscopy (SEIRAS) is a suitable method for investigating electrocatalytic processes because it can monitor with chemical specificity the mechanisms of the reactions. However, it remains difficult to detect many relevant aspects of electrochemical reactions such as short-lived intermediates. Herein, an integrated nanophotonic-electrochemical SEIRAS platform is developed and experimentally realized for the in situ investigation of molecular signal traces emerging during electrochemical experiments. A platinum nano-slot metasurface featuring strongly enhanced electromagnetic near fields is implemented and spectrally targets the weak vibrational mode of the adsorbed carbon monoxide at ≈2033 cm−1. The metasurface-driven resonances can be tuned over a broad range in the mid-infrared spectrum and provide high molecular sensitivity. Compared to conventional unstructured platinum films, this nanophotonic-electrochemical platform delivers a 27-fold improvement of the experimentally detected characteristic absorption signals, enabling the detection of new species with weak signals, fast conversions, or low surface concentrations. By providing a deeper understanding of catalytic reactions, the nanophotonic-electrochemical platform is anticipated to open exciting perspectives for electrochemical SEIRAS, surface-enhanced Raman spectroscopy, and other fields of chemistry such as photoelectrocatalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Nanomechanics with plasmonic nanoantennas: ultrafast and local exchange between electromagnetic and mechanical energy},

author = {A V Bragas and S A Maier and H D Boggiano and G Grinblat and R Bert\'{e} and L D S Menezes and E Cort\'{e}s},

url = {https://opg.optica.org/josab/abstract.cfm?doi=10.1364/JOSAB.482384},

doi = {https://doi.org/10.1364/JOSAB.482384},

year  = {2023},

date = {2023-03-10},

journal = {J. Opt. Soc. Am. B},

abstract = {Converted into mechanical nanoresonators after optical pulsed excitation and electron decay into coherent acoustic phonons, plasmonic nanoantennas produce a periodic modulation of their optical properties, allowing, in turn, an optical reading of these extremely small movements. In this work we review the physics of these nanoresonators and their acoustic vibrations, whose frequencies are in the range of a few to tens of GHz. The accurate determination of their oscillation frequencies allows them to act as mechanical nanoprobes, measure local mechanical moduli of the environment, and perform high-resolution imaging using phononic reconstruction. Furthermore, the internal and external damping mechanisms which affect the quality factor of the nanoresonator and, in particular, the role of the substrate when the nanoantennas are integrated into platforms and probed individually are also reviewed. Finally, we discuss the all-optical generation of hypersonic surface acoustic waves with nanoantennas and the importance of their manipulation for potential acousto-plasmonic devices operating in the GHz range and the nanoscale.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Atomically Local Electric Field Induced Interface Water Reorientation for Alkaline Hydrogen Evolution Reaction},

author = {C Cai and K Liu and L Zhang and F Li and Y Tan and P Li and Y Wang and M Wang and Z Feng and D Motta Meira and W Qu and A Stefancu and W Li and H Li and J Fu and H Wang and D Zhang and E Cort\'{e}s and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202300873},

doi = {https://doi.org/10.1002/anie.202300873},

issn = {1433-7851},

year  = {2023},

date = {2023-03-08},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

pages = {e202300873},

abstract = {Abstract The slow water dissociation process in alkaline electrolyte severely limits the kinetics of HER. The orientation of H2O is well known to affect the dissociation process, but H2O orientation is hard to control because of its random distribution. Herein, an atomically asymmetric local electric field was designed by IrRu dizygotic single-atom sites (IrRu DSACs) to tune the H2O adsorption configuration and orientation, thus optimizing its dissociation process. The electric field intensity of IrRu DSACs is over 4.00×1010 N/C. The ab initio molecular dynamics simulations combined with in situ Raman spectroscopy analysis on the adsorption behavior of H2O show that the M−H bond length (M=active site) is shortened at the interface due to the strong local electric field gradient and the optimized water orientation promotes the dissociation process of interfacial water. This work provides a new way to explore the role of single atomic sites in alkaline hydrogen evolution reaction.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Interface-Dependent Selectivity in Plasmon-Driven Chemical Reactions},

author = {A Stefancu and J Gargiulo and G Laufersky and B Augui\'{e} and V Chi\c{s} and E C Le Ru and M Liu and N Leopold and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsnano.2c12116},

doi = {10.1021/acsnano.2c12116},

issn = {1936-0851},

year  = {2023},

date = {2023-02-01},

journal = {ACS Nano},

volume = {17},

number = {3},

pages = {3119-3127},

abstract = {Plasmonic nanoparticles can drive chemical reactions powered by sunlight. These processes involve the excitation of surface plasmon resonances (SPR) and the subsequent charge transfer to adsorbed molecular orbitals. Nonetheless, controlling the flow of energy and charge from SPR to adsorbed molecules is still difficult to predict or tune. Here, we show the crucial role of halide ions in modifying the energy landscape of a plasmon-driven chemical reaction by carefully engineering the nanoparticle\textendashmolecule interface. By doing so, the selectivity of plasmon-driven chemical reactions can be controlled, either enhancing or inhibiting the metal\textendashmolecule charge and energy transfer or by regulating the vibrational pumping rate. These results provide an elegant method for controlling the energy flow from plasmonic nanoparticles to adsorbed molecules, in situ, and selectively targeting chemical bonds by changing the chemical nature of the metal\textendashmolecule interface.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Light-activated catalysts point the way to sustainable chemistry},

author = {E Cort\'{e}s},

doi = {10.1038/d41586-023-00239-2},

issn = {0028-0836},

year  = {2023},

date = {2023-02-01},

journal = {Nature},

volume = {614},

number = {7947},

pages = {230-232},

abstract = {A light-activated ‘plasmonic’ catalyst, made from abundant elements, produces as much hydrogen from ammonia as do the most-used heat-activated catalysts based on a rarer element, suggesting a strategy for sustainable chemical production.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Highly selective monomethylation of amines with CO2/H2 via Ag/Al2O3 as catalyst},

author = {Y Long and J He and H Zhang and Y Chen and K Liu and J Fu and H Li and L Zhu and Z Lin and A Stefancu and E Cortes and M Zhu and M Liu},

url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/chem.202203152},

doi = {https://doi.org/10.1002/chem.202203152},

issn = {0947-6539},

year  = {2023},

date = {2023-01-10},

journal = {Chemistry \textendash A European Journal},

volume = {n/a},

number = {n/a},

abstract = {The selective synthesis of monomethylated amines with CO2 is particularly challenging because the formation of tertiary amines is thermodynamically more favorable. Here we explore a new strategy for the controllable synthesis of N-monomethylated amines from primary amines and CO2/H2. Our first-principle calculations reveal that the dissociation of H2 via an heterolytic route reduces the reactivity of methylated amines and thus inhibit successive methylation. In-situ DRIFTS prove the process of formation and decomposition of ammonium salt by secondary amine reversible binding with H+ on the Ag/Al2O3 catalyst, thereby reducing its reactivity. Meanwhile, the energy barrier for rate-determining step of monomehylation was much lower than that of over methylation (0.34 eV vs 0.58 eV) means amines monomethylation in preference to successive methylation. Under optimal reaction conditions, a variety of amines conversion to corresponding monomethylated amines in good to excellent yields, and more than 90% yield of product obtained.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Subsurface Engineering Induced Fermi Level De-pinning in Metal Oxide Semiconductors for Photoelectrochemical Water Splitting},

author = {J Wang and G Ni and W Liao and K Liu and J Chen and F Liu and Z Zhang and M Jia and J Li and J Fu and E Pensa and L Jiang and Z Bian and E Cortes and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202217026},

doi = {https://doi.org/10.1002/anie.202217026},

issn = {1433-7851},

year  = {2022},

date = {2022-12-28},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

abstract = {Photoelectrochemical (PEC) water splitting is a promising approach for renewable solar light conversion. However, surface Fermi level pinning (FLP), caused by surface trap states, severely restricts the PEC activities. Theoretical calculations indicate subsurface oxygen vacancy (sub-Ov) could release the FLP and retain the active structure. A series of metal oxide semiconductors with sub-Ov were prepared through precisely regulated spin-coating and calcination. Etching X-ray photoelectron spectroscopy (XPS), scanning transmission electron microscopy (STEM), and electron energy loss spectra (EELS) demonstrated Ov located at sub ~2-5 nm region. Mott-Schottky and open circuit photovoltage results confirmed the surface trap states elimination and Fermi level de-pinning. Thus, superior PEC performances of 5.1, 3.4, and 2.1 mA cm-2 at 1.23 V vs. RHE were achieved on BiVO4, Bi2O3, TiO2 with outstanding stability for 72 h, outperforming most reported works under the identical conditions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Boosting Nitrogen Activation via Ag Nanoneedle Arrays for Efficient Ammonia Synthesis},

author = {W Liao and K Liu and J Wang and A Stefancu and Q Chen and K Wu and Y Zhou and H Li and L Mei and M Li and J Fu and M Miyauchi and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1021/acsnano.2c08853},

doi = {10.1021/acsnano.2c08853},

issn = {1936-0851},

year  = {2022},

date = {2022-12-16},

journal = {ACS Nano},

abstract = {Electrocatalytic N2 reduction reaction (eNRR) provides a promising carbon-neutral and sustainable ammonia-synthesizing alternative to the Haber-Bosch process. However, the nonpolar N2 has significant thermodynamic stability and requires ultrahigh energy to break down the N≡N bond. Here, we report the construction of local enhanced electric fields (LEEFs) by Ag nanoneedle arrays to promote N≡N fracture thus assisting the eNRR. The LEEFs could induce charge polarization on nitrogen atoms and reduce the energy barrier in the N2 first-protonation step. The detected N─N and N─H intermediates prove the cleavage of the N≡N bond and the hydrogenation of N2 by LEEFs. The increased LEEFs lead to logarithmic growth rates for the targeted eNRR and exponential growth rates for the unavoidable competitive hydrogen evolution reaction. Thus, regulation and tuning of LEEFs to ∼4 × 104 kV m\textendash1 endows the raise of eNRR to the summit, achieving high ammonia selectivity with a Faradaic efficiency of 72.3 ± 4.0%.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Near-Field Retrieval of the Surface Phonon Polariton Dispersion in Free-Standing Silicon Carbide Thin Films},

author = {A Mancini and L Nan and F J Wendisch and R Bert\'{e} and H Ren and E Cort\'{e}s and S A Maier},

url = {https://doi.org/10.1021/acsphotonics.2c01270},

doi = {10.1021/acsphotonics.2c01270},

year  = {2022},

date = {2022-10-20},

journal = {ACS Photonics},

abstract = {Surface phonon polaritons (SPhPs) are mixed light-matter states originating from strong coupling of photons with lattice vibrations. Thin films of polar dielectrics feature a splitting of the SPhP branch due to the hybridization of the top and bottom interface modes. Recently, enhanced in-plane thermal conductivity and near-field energy transfer have been experimentally demonstrated in free-standing polar films. These effects are determined by the SPhP dispersion in these systems, which, however, is yet to be reported experimentally. In this work, we retrieve the SPhP dispersion in silicon carbide free-standing membranes few hundreds of nanometers thick through near-field spectroscopy. We find several branches in the experimental dispersion, which we rationalize as multiple reflections of tip and edge launched SPhPs, in good agreement with theoretical predictions. Our work paves the way to employ large-area free-standing membranes as a platform for phonon polaritonics, with foreseeable applications in the field of thermal management at the nanoscale.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Attenuating metal-substrate conjugation in atomically dispersed nickel catalysts for electroreduction of CO2 to CO},

author = {Q Wang and K Liu and K Hu and C Cai and H Li and H Li and M Herran and Y-R Lu and T-S Chan and C Ma and J Fu and S Zhang and Y Liang and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1038/s41467-022-33692-0},

doi = {10.1038/s41467-022-33692-0},

issn = {2041-1723},

year  = {2022},

date = {2022-10-14},

journal = {Nature Communications},

volume = {13},

number = {1},

pages = {6082},

abstract = {Atomically dispersed transition metals on carbon-based aromatic substrates are an emerging class of electrocatalysts for the electroreduction of CO2. However, electron delocalization of the metal site with the carbon support via d-π conjugation strongly hinders CO2 activation at the active metal centers. Herein, we introduce a strategy to attenuate the d-π conjugation at single Ni atomic sites by functionalizing the support with cyano moieties. In situ attenuated total reflection infrared spectroscopy and theoretical calculations demonstrate that this strategy increases the electron density around the metal centers and facilitates CO2 activation. As a result, for the electroreduction of CO2 to CO in aqueous KHCO3 electrolyte, the cyano-modified catalyst exhibits a turnover frequency of ~22,000 per hour at −1.178 V versus the reversible hydrogen electrode (RHE) and maintains a Faradaic efficiency (FE) above 90% even with a CO2 concentration of only 30% in an H-type cell. In a flow cell under pure CO2 at −0.93 V versus RHE the cyano-modified catalyst enables a current density of −300 mA/cm2 with a FE above 90%.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Heteroatoms Induce Localization of the Electric Field and Promote a Wide Potential-Window Selectivity Towards CO in the CO2 Electroreduction},

author = {C Cai and B Liu and K Liu and P Li and J Fu and Y Wang and W Li and C Tian and Y Kang and A Stefancu and H Li and C-W Kao and T-S Chan and Z Lin and L Chai and E Cort\'{e}s and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202212640},

doi = {https://doi.org/10.1002/anie.202212640},

issn = {1433-7851},

year  = {2022},

date = {2022-09-08},

journal = {Angewandte Chemie International Edition},

volume = {61},

number = {44},

pages = {e202212640},

abstract = {Abstract Carbon dioxide electroreduction (CO2RR) is a sustainable way of producing carbon-neutral fuels. Product selectivity in CO2RR is regulated by the adsorption energy of reaction-intermediates. Here, we employ differential phase contrast-scanning transmission electron microscopy (DPC-STEM) to demonstrate that Sn heteroatoms on a Ag catalyst generate very strong and atomically localized electric fields. In situ attenuated total reflection infrared spectroscopy (ATR-IR) results verified that the localized electric field enhances the adsorption of *COOH, thus favoring the production of CO during CO2RR. The Ag/Sn catalyst exhibits an approximately 100 % CO selectivity at a very wide range of potentials (from −0.5 to −1.1 V, versus reversible hydrogen electrode), and with a remarkably high energy efficiency (EE) of 76.1 %.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Tailoring Plasmonic Bimetallic Nanocatalysts Toward Sunlight-Driven H2 Production},

author = {M Herran and A Sousa-Castillo and C Fan and S Lee and W Xie and M D\"{o}blinger and B Augui\'{e} and E Cort\'{e}s},

url = {https://doi.org/10.1002/adfm.202203418},

doi = {https://doi.org/10.1002/adfm.202203418},

issn = {1616-301X},

year  = {2022},

date = {2022-09-01},

journal = {Advanced Functional Materials},

volume = {32},

number = {38},

pages = {2203418},

abstract = {Abstract Hybrid nanoparticles combining plasmonic and catalytic components have recently gained interest for their potential use in sunlight-to-chemical energy conversion. However, a deep understanding of the structure?performance that maximizes the use of the incoming energy remains elusive. Here, a suite of Au and Pd based nanostructures in core?shell and core-satellites configurations are designed and their photocatalytic activity for Hydrogen (H2) generation under sunlight illumination is tested. Formic acid is employed as H2 source. Core-satellite systems show a higher enhancement of the reaction upon illumination, compared to core?shell ones. Electromagnetic simulations reveal that a key difference between both configurations is the excitation of highly localized and asymmetric electric fields in the gap between both materials. In this scheme, the core Au particle acts as an antenna, efficiently capturing visible light via the excitation of localized plasmon resonances, while the surrounding Pd satellites transduce the locally-enhanced electric field into catalytic activity. These findings advance the understanding of plasmon-driven photocatalysis, and provide an important benchmark to guide the design of the next generation of plasmonic bimetallic nanostructures.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Introducing a Symmetry-Breaking Coupler into a Dielectric Metasurface Enables Robust High-Q Quasi-BICs},

author = {G Q Moretti and A Tittl and E Cort\'{e}s and S A Maier and A V Bragas and G Grinblat},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adpr.202200111},

doi = {https://doi.org/10.1002/adpr.202200111},

issn = {2699-9293},

year  = {2022},

date = {2022-08-21},

journal = {Advanced Photonics Research},

volume = {n/a},

number = {n/a},

pages = {2200111},

abstract = {Dielectric metasurfaces supporting quasibound states in the continuum (quasi-BICs) exhibit very high-quality factor resonances and electric field confinement. However, accessing the high-Q end of the quasi-BIC regime usually requires marginally distorting the metasurface design from a BIC condition, pushing the needed nanoscale fabrication precision to the limit. This work introduces a novel concept for generating high-Q quasi-BICs, which strongly relaxes this requirement by incorporating a relatively large perturbative element close to high-symmetry points of an undistorted BIC metasurface, acting as a coupler to the radiation continuum. This approach is validated by adding a ≈100 nm diameter cylinder between two reflection-symmetry points separated by a 300 nm gap in an elliptical disk metasurface unit cell, using gallium phosphide as the dielectric. It is found that high-Q resonances emerge when the cylindrical coupler is placed at any position between such symmetry points. This metasurface's second harmonic generation capability in the optical range is further explored. Displacing the coupler as much as a full diameter from a BIC condition produces record-breaking normalized conversion efficiencies \>102 W−1. The strategy of enclosing a disruptive element between multiple high-symmetry points in a BIC metasurface can be applied to construct robust high-Q quasi-BICs in many geometrical designs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Catalytic Metasurfaces Empowered by Bound States in the Continuum},

author = {H Hu and T Weber and O Bienek and A Wester and L H\"{u}ttenhofer and I D Sharp and S A Maier and A Tittl and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsnano.2c05680},

doi = {10.1021/acsnano.2c05680},

issn = {1936-0851},

year  = {2022},

date = {2022-08-11},

journal = {ACS Nano},

volume = {16},

number = {8},

pages = {13057-13068},

abstract = {Photocatalytic platforms based on ultrathin reactive materials facilitate carrier transport and extraction but are typically restricted to a narrow set of materials and spectral operating ranges due to limited absorption and poor energy-tuning possibilities. Metasurfaces, a class of 2D artificial materials based on the electromagnetic design of nanophotonic resonators, allow optical absorption engineering for a wide range of materials. Moreover, tailored resonances in nanostructured materials enable strong absorption enhancement and thus carrier multiplication. Here, we develop an ultrathin catalytic metasurface platform that leverages the combination of loss-engineered substoichiometric titanium oxide (TiO2\textendashx) and the emerging physical concept of optical bound states in the continuum (BICs) to boost photocatalytic activity and provide broad spectral tunability. We demonstrate that our platform reaches the condition of critical light coupling in a TiO2\textendashx BIC metasurface, thus providing a general framework for maximizing light\textendashmatter interactions in diverse photocatalytic materials. This approach can avoid the long-standing drawbacks of many naturally occurring semiconductor-based ultrathin films applied in photocatalysis, such as poor spectral tunability and limited absorption manipulation. Our results are broadly applicable to fields beyond photocatalysis, including photovoltaics and photodetectors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Identification of the Highly Active Co\textendashN4 Coordination Motif for Selective Oxygen Reduction to Hydrogen Peroxide},

author = {S Chen and T Luo and X Li and K Chen and J Fu and K Liu and C Cai and Q Wang and H Li and Y Chen and C Ma and L Zhu and Y-R Lu and T-S Chan and M Zhu and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1021/jacs.2c01194},

doi = {10.1021/jacs.2c01194},

issn = {0002-7863},

year  = {2022},

date = {2022-08-03},

journal = {Journal of the American Chemical Society},

volume = {144},

number = {32},

pages = {14505-14516},

abstract = {Electrosynthesis of hydrogen peroxide (H2O2) through oxygen reduction reaction (ORR) is an environment-friendly and sustainable route for obtaining a fundamental product in the chemical industry. Co\textendashN4 single-atom catalysts (SAC) have sparkled attention for being highly active in both 2e\textendash ORR, leading to H2O2 and 4e\textendash ORR, in which H2O is the main product. However, there is still a lack of fundamental insights into the structure\textendashfunction relationship between CoN4 and the ORR mechanism over this family of catalysts. Here, by combining theoretical simulation and experiments, we unveil that pyrrole-type CoN4 (Co\textendashN SACDp) is mainly responsible for the 2e\textendash ORR, while pyridine-type CoN4 catalyzes the 4e\textendash ORR. Indeed, Co\textendashN SACDp exhibits a remarkable H2O2 selectivity of 94% and a superb H2O2 yield of 2032 mg for 90 h in a flow cell, outperforming most reported catalysts in acid media. Theoretical analysis and experimental investigations confirm that Co\textendashN SACDp─with weakening O2/HOO* interaction─boosts the H2O2 production.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Ordered Ag Nanoneedle Arrays with Enhanced Electrocatalytic CO2 Reduction via Structure-Induced Inhibition of Hydrogen Evolution},

author = {Q Chen and K Liu and Y Zhou and X Wang and K Wu and H Li and E Pensa and J Fu and M Miyauchi and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1021/acs.nanolett.2c01853},

doi = {10.1021/acs.nanolett.2c01853},

issn = {1530-6984},

year  = {2022},

date = {2022-08-01},

journal = {Nano Letters},

volume = {22},

number = {15},

pages = {6276-6284},

abstract = {Silver is an attractive catalyst for converting CO2 into CO. However, the high CO2 activation barrier and the hydrogen evolution side reaction seriously limit its practical application and industrial perspective. Here, an ordered Ag nanoneedle array (Ag-NNAs) was prepared by template-assisted vacuum thermal-evaporation for CO2 electroreduction into CO. The nanoneedle array structure induces a strong local electric field at the tips, which not only reduces the activation barrier for CO2 electroreduction but also increases the energy barrier for the hydrogen evolution reaction (HER). Moreover, the array structure endows a high surface hydrophobicity, which can regulate the adsorption of water molecules at the interface and thus dynamically inhibit the competitive HER. As a result, the optimal Ag-NNAs exhibits 91.4% Faradaic efficiency (FE) of CO for over 700 min at −1.0 V vs RHE. This work provides a new concept for the application of nanoneedle array structures in electrocatalytic CO2 reduction reactions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Mechanistic Insights into OC\textendashCOH Coupling in CO2 Electroreduction on Fragmented Copper},

author = {K Yao and J Li and H Wang and R Lu and X Yang and M Luo and N Wang and Z Wang and C Liu and T Jing and S Chen and E Cort\'{e}s and S A Maier and S Zhang and T Li and Y Yu and Y Liu and X Kang and H Liang},

url = {https://doi.org/10.1021/jacs.2c01044},

doi = {10.1021/jacs.2c01044},

issn = {0002-7863},

year  = {2022},

date = {2022-07-29},

journal = {Journal of the American Chemical Society},

volume = {144},

number = {31},

pages = {14005-14011},

abstract = {The carbon\textendashcarbon (C\textendashC) bond formation is essential for the electroconversion of CO2 into high-energy-density C2+ products, and the precise coupling pathways remain controversial. Although recent computational investigations have proposed that the OC\textendashCOH coupling pathway is more favorable in specific reaction conditions than the well-known CO dimerization pathway, the experimental evidence is still lacking, partly due to the separated catalyst design and mechanistic/spectroscopic exploration. Here, we employ density functional theory calculations to show that on low-coordinated copper sites, the *CO bindings are strengthened, and the adsorbed *CO coupling with their hydrogenation species, *COH, receives precedence over CO dimerization. Experimentally, we construct a fragmented Cu catalyst with abundant low-coordinated sites, exhibiting a 77.8% Faradaic efficiency for C2+ products at 300 mA cm\textendash2. With a suite of in situ spectroscopic studies, we capture an *OCCOH intermediate on the fragmented Cu surfaces, providing direct evidence to support the OC\textendashCOH coupling pathway. The mechanistic insights of this research elucidate how to design materials in favor of OC\textendashCOH coupling toward efficient C2+ production from CO2 reduction.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Imaging elliptically polarized infrared near-fields on nanoparticles by strong-field dissociation of functional surface groups},

author = {P Rosenberger and R Dagar and W Zhang and A Sousa-Castillo and M Neuhaus and E Cortes and S A Maier and C Costa-Vera and M F Kling and B Bergues},

url = {https://doi.org/10.1140/epjd/s10053-022-00430-6},

doi = {10.1140/epjd/s10053-022-00430-6},

issn = {1434-6079},

year  = {2022},

date = {2022-06-27},

journal = {The European Physical Journal D},

volume = {76},

number = {6},

pages = {109},

abstract = {We investigate the strong-field ion emission from the surface of isolated silica nanoparticles aerosolized from an alcoholic solution, and demonstrate the applicability of the recently reported near-field imaging at 720 nm [Rupp et al., Nat. Comm., 10(1):4655, 2019] to longer wavelength (2 $$mu $$m) and polarizations with arbitrary ellipticity. Based on the experimental observations, we discuss the validity of a previously introduced semi-classical model, which is based on near-field driven charge generation by a Monte-Carlo approach and classical propagation. We furthermore clarify the role of the solvent in the surface composition of the nanoparticles in the interaction region. We find that upon injection of the nanoparticles into the vacuum, the alcoholic solvent evaporates on millisecond time scales, and that the generated ions originate predominantly from covalent bonds with the silica surface rather than from physisorbed solvent molecules. These findings have important implications for the development of future theoretical models of the strong-field ion emission from silica nanoparticles, and the application of near-field imaging and reaction dynamics of functional groups on isolated nanoparticles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optical Metasurfaces for Energy Conversion},

author = {E Cort\'{e}s and F J Wendisch and L Sortino and A Mancini and S Ezendam and S Saris and L De S. Menezes and A Tittl and H Ren and S A Maier},

url = {https://doi.org/10.1021/acs.chemrev.2c00078},

doi = {10.1021/acs.chemrev.2c00078},

issn = {0009-2665},

year  = {2022},

date = {2022-06-21},

journal = {Chemical Reviews},

volume = {122},

number = {19},

pages = {15082-15176},

abstract = {Nanostructured surfaces with designed optical functionalities, such as metasurfaces, allow efficient harvesting of light at the nanoscale, enhancing light\textendashmatter interactions for a wide variety of material combinations. Exploiting light-driven matter excitations in these artificial materials opens up a new dimension in the conversion and management of energy at the nanoscale. In this review, we outline the impact, opportunities, applications, and challenges of optical metasurfaces in converting the energy of incoming photons into frequency-shifted photons, phonons, and energetic charge carriers. A myriad of opportunities await for the utilization of the converted energy. Here we cover the most pertinent aspects from a fundamental nanoscopic viewpoint all the way to applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {All-optical nanoscopic spatial control of molecular reaction yields on nanoparticles},

author = {W Zhang and R Dagar and P Rosenberger and A Sousa-Castillo and M Neuhaus and W Li and S A Khan and A S Alnaser and E Cortes and S A Maier and C Costa-Vera and M F Kling and B Bergues},

url = {http://opg.optica.org/optica/abstract.cfm?URI=optica-9-5-551},

doi = {10.1364/OPTICA.453915},

year  = {2022},

date = {2022-05-20},

journal = {Optica},

volume = {9},

number = {5},

pages = {551-560},

abstract = {Molecular adsorbate reactions on nanoparticles play a fundamental role in areas such as nano-photocatalysis, atmospheric, and astrochemistry. They can be induced, enhanced, and controlled by field localization and enhancement on the nanoparticle surface. In particular, the ability to perform highly controlled near-field-mediated reactions is key to deepening our understanding of surface photoactivity on nanosystems. Here, using reaction nanoscopy, we experimentally demonstrate all-optical nanoscopic control of surface reaction yields by tailoring the near fields on nanoparticles with waveform-controlled linear and bicircular two-color laser pulses, respectively. We observe site-selective proton emission from the dissociative ionization of adsorbate molecules on SiO2 nanoparticles as a function of the polarization and relative phase of the two-color pulses. The angularly resolved close-to-uniform mapping between the surface reaction yields and the measured ion momentum enables the observation and spatial control of molecular reactions on the nanoparticle surface with nanoscopic resolution. The experimental results are modeled and reproduced qualitatively by classical trajectory Monte Carlo simulations. Our work paves the way toward reliable all-optical control of photocatalytic chemical reactions on nanoscale surfaces.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Controlling Plasmonic Chemistry Pathways through Specific Ion Effects},

author = {A Stefancu and L Nan and L Zhu and V Chiș and I Bald and M Liu and N Leopold and S A Maier and E Cortes},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202200397},

doi = {https://doi.org/10.1002/adom.202200397},

issn = {2195-1071},

year  = {2022},

date = {2022-05-11},

journal = {Advanced Optical Materials},

volume = {n/a},

number = {n/a},

pages = {2200397},

abstract = {Abstract Plasmon-driven dehalogenation of brominated purines has been recently explored as a model system to understand fundamental aspects of plasmon-assisted chemical reactions. Here, it is shown that divalent Ca2+ ions strongly bridge the adsorption of bromoadenine (Br-Ade) to Ag surfaces. Such ion-mediated binding increases the molecule's adsorption energy leading to an overlap of the metal energy states and the molecular states, enabling the chemical interface damping (CID) of the plasmon modes of the Ag nanostructures (i.e., direct electron transfer from the metal to Br-Ade). Consequently, the conversion of Br-Ade to adenine almost doubles following the addition of Ca2+. These experimental results, supported by theoretical calculations of the local density of states of the Ag/Br-Ade complex, indicate a change of the charge transfer pathway driving the dehalogenation reaction, from Landau damping (in the lack of Ca2+ ions) to CID (after the addition of Ca2+). The results show that the surface dynamics of chemical species (including water molecules) play an essential role in charge transfer at plasmonic interfaces and cannot be ignored. It is envisioned that these results will help in designing more efficient nanoreactors, harnessing the full potential of plasmon-assisted chemistry.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Introducing a Symmetry-Breaking Coupler into a Dielectric Metasurface Enables Robust High-Q Quasibound States in the Continuum and Efficient Nonlinear Frequency Conversion},

author = {G Q Moretti and A Tittl and E Cort\'{e}s and S A Maier and A V Bragas and G Grinblat},

url = {https://doi.org/10.48550/arXiv.2204.07097},

doi = {https://doi.org/10.48550/arXiv.2204.07097},

year  = {2022},

date = {2022-04-14},

journal = {arXiv preprint arXiv:2204.07097},

abstract = {Dielectric metasurfaces supporting quasi-bound states in the continuum (quasi-BICs) exhibit very high quality factor resonances and electric field confinement. However, accessing the high-Q end of the quasi-BIC regime usually requires marginally distorting the metasurface design from a BIC condition, pushing the needed nanoscale fabrication precision to the limit. This work introduces a novel concept for generating high-Q quasi-BICs, which strongly relaxes this requirement by incorporating a relatively large perturbative element close to high-symmetry points of an undistorted BIC metasurface, acting as a coupler to the radiation continuum. We validate this approach by adding a ∼100 nm diameter cylinder between two reflection-symmetry points separated by a 300 nm gap in an elliptical disk metasurface unit cell, using gallium phosphide as the dielectric. We find that high-Q resonances emerge when the cylindrical coupler is placed at any position between such symmetry points. We further explore this metasurface's second harmonic generation capability in the optical range. Displacing the coupler as much as a full diameter from a BIC condition produces record-breaking normalized conversion efficiencies \>102 W−1. The strategy of enclosing a disruptive element between multiple high-symmetry points in a BIC metasurface could be applied to construct robust high-Q quasi-BICs in many geometrical designs.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Experimental characterization techniques for plasmon-assisted chemistry},

author = {E Cort\'{e}s and R Grzeschik and S A Maier and S Schl\"{u}cker},

doi = {10.1038/s41570-022-00368-8},

issn = {2397-3358},

year  = {2022},

date = {2022-03-28},

journal = {Nat Rev Chem},

volume = {6},

number = {4},

pages = {259-274},

abstract = {Plasmon-assisted chemistry is the result of a complex interplay between electromagnetic near fields, heat and charge transfer on the nanoscale. The disentanglement of their roles is non-trivial. Therefore, a thorough knowledge of the chemical, structural and spectral properties of the plasmonic/molecular system being used is required. Specific techniques are needed to fully characterize optical near fields, temperature and hot carriers with spatial, energetic and/or temporal resolution. The timescales for all relevant physical and chemical processes can range from a few femtoseconds to milliseconds, which necessitates the use of time-resolved techniques for monitoring the underlying dynamics. In this Review, we focus on experimental techniques to tackle these challenges. We further outline the difficulties when going from the ensemble level to single-particle measurements. Finally, a thorough understanding of plasmon-assisted chemistry also requires a substantial joint experimental and theoretical effort.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Vertical Cu Nanoneedle Arrays Enhance the Local Electric Field Promoting C2 Hydrocarbons in the CO2 Electroreduction},

author = {Y Zhou and Y Liang and J Fu and K Liu and Q Chen and X Wang and H Li and L Zhu and J Hu and H Pan and M Miyauchi and L Jiang and E Cort\'{e}s and M Liu},

url = {https://doi.org/10.1021/acs.nanolett.1c04653},

doi = {10.1021/acs.nanolett.1c04653},

issn = {1530-6984},

year  = {2022},

date = {2022-02-15},

journal = {Nano Letters},

abstract = {Electrocatalytic reduction of CO2 to multicarbon products is a potential strategy to solve the energy crisis while achieving carbon neutrality. To improve the efficiency of multicarbon products in Cu-based catalysts, optimizing the *CO adsorption and reducing the energy barrier for carbon\textendashcarbon (C\textendashC) coupling are essential features. In this work, a strong local electric field is obtained by regulating the arrangement of Cu nanoneedle arrays (CuNNAs). CO2 reduction performance tests indicate that an ordered nanoneedle array reaches a 59% Faraday efficiency for multicarbon products (FEC2) at −1.2 V (vs RHE), compared to a FEC2 of 20% for a disordered nanoneedle array (CuNNs). As such, the very high and local electric fields achieved by an ordered Cu nanoneedle array leads to the accumulation of K+ ions, which benefit both *CO adsorption and C\textendashC coupling. Our results contribute to the design of highly efficient catalysts for multicarbon products.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Halide\textendashMetal Complexes at Plasmonic Interfaces Create New Decay Pathways for Plasmons and Excited Molecules},

author = {A Stefancu and O M Biro and O Todor-Boer and I Botiz and E Cort\'{e}s and N Leopold},

url = {https://doi.org/10.1021/acsphotonics.1c01714},

doi = {10.1021/acsphotonics.1c01714},

year  = {2022},

date = {2022-02-10},

journal = {ACS Photonics},

abstract = {We show that by modifying the chemical interface of silver nanoparticles (AgNPs) with halide ions, it is possible to tune the total decay rate of adsorbed excited molecules and the plasmon damping rate. Through single-molecule surface-enhanced Raman scattering and surface-enhanced fluorescence enhancement factors of crystal violet (CV) and rhodamine 6G (R6G), we show that I\textendash-modified AgNPs (AgNPs@I) and Br\textendash-modified AgNPs (AgNPs@Br) lead to an increase in the total decay rate of excited CV and R6G by a factor between ∼1.6\textendash2.6, compared to Cl\textendash-modified AgNPs (AgNPs@Cl). In addition, we found that the chemical interface damping, which characterizes the plasmon resonance decay into surface states, is stronger on AgNPs@I and AgNPs@Br when compared to AgNPs@Cl. These results point toward the formation of metal\textendashhalide surface complexes. These new interfacial states can accept electrons from both excited molecular orbitals and surface plasmon excitations, completely altering the electronic dynamics and reactivity of plasmonic interfaces.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Accelerating CO2 Electroreduction to Multicarbon Products via Synergistic Electric\textendashThermal Field on Copper Nanoneedles},

author = {B Yang and K Liu and H Li and C Liu and J Fu and H Li and J E Huang and P Ou and T Alkayyali and C Cai and Y Duan and H Liu and P An and N Zhang and W Li and X Qiu and C Jia and J Hu and L Chai and Z Lin and Y Gao and M Miyauchi and E Cort\'{e}s and S A Maier and M Liu},

url = {https://doi.org/10.1021/jacs.1c11253},

doi = {10.1021/jacs.1c11253},

issn = {0002-7863},

year  = {2022},

date = {2022-02-03},

urldate = {2022-02-03},

journal = {Journal of the American Chemical Society},

abstract = {Electrochemical CO2 reduction is a promising way to mitigate CO2 emissions and close the anthropogenic carbon cycle. Among products from CO2RR, multicarbon chemicals, such as ethylene and ethanol with high energy density, are more valuable. However, the selectivity and reaction rate of C2 production are unsatisfactory due to the sluggish thermodynamics and kinetics of C\textendashC coupling. The electric field and thermal field have been studied and utilized to promote catalytic reactions, as they can regulate the thermodynamic and kinetic barriers of reactions. Either raising the potential or heating the electrolyte can enhance C\textendashC coupling, but these come at the cost of increasing side reactions, such as the hydrogen evolution reaction. Here, we present a generic strategy to enhance the local electric field and temperature simultaneously and dramatically improve the electric\textendashthermal synergy desired in electrocatalysis. A conformal coating of ∼5 nm of polytetrafluoroethylene significantly improves the catalytic ability of copper nanoneedles (∼7-fold electric field and ∼40 K temperature enhancement at the tips compared with bare copper nanoneedles experimentally), resulting in an improved C2 Faradaic efficiency of over 86% at a partial current density of more than 250 mA cm\textendash2 and a record-high C2 turnover frequency of 11.5 ± 0.3 s\textendash1 Cu site\textendash1. Combined with its low cost and scalability, the electric\textendashthermal strategy for a state-of-the-art catalyst not only offers new insight into improving activity and selectivity of value-added C2 products as we demonstrated but also inspires advances in efficiency and/or selectivity of other valuable electro-/photocatalysis such as hydrogen evolution, nitrogen reduction, and hydrogen peroxide electrosynthesis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Hybrid Plasmonic Nanomaterials for Hydrogen Generation and Carbon Dioxide Reduction},

author = {S Ezendam and M Herran and L Nan and C Gruber and Y Kang and F Gr\"{o}bmeyer and R Lin and J Gargiulo and A Sousa-Castillo and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsenergylett.1c02241},

doi = {10.1021/acsenergylett.1c02241},

year  = {2022},

date = {2022-01-24},

urldate = {2022-01-24},

journal = {ACS Energy Letters},

pages = {778-815},

abstract = {The successful development of artificial photosynthesis requires finding new materials able to efficiently harvest sunlight and catalyze hydrogen generation and carbon dioxide reduction reactions. Plasmonic nanoparticles are promising candidates for these tasks, due to their ability to confine solar energy into molecular regions. Here, we review recent developments in hybrid plasmonic photocatalysis, including the combination of plasmonic nanomaterials with catalytic metals, semiconductors, perovskites, 2D materials, metal\textendashorganic frameworks, and electrochemical cells. We perform a quantitative comparison of the demonstrated activity and selectivity of these materials for solar fuel generation in the liquid phase. In this way, we critically assess the state-of-the-art of hybrid plasmonic photocatalysts for solar fuel production, allowing its benchmarking against other existing heterogeneous catalysts. Our analysis allows the identification of the best performing plasmonic systems, useful to design a new generation of plasmonic catalysts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Nickel polyphthalocyanine with electronic localization at the nickel site for enhanced CO2 reduction reaction},

author = {K Chen and M Cao and G Ni and S Chen and H Liao and L Zhu and H Li and J Fu and J Hu and E Cort\'{e}s and M Liu},

url = {https://www.sciencedirect.com/science/article/pii/S0926337322000339},

doi = {https://doi.org/10.1016/j.apcatb.2022.121093},

issn = {0926-3373},

year  = {2022},

date = {2022-01-09},

journal = {Applied Catalysis B: Environmental},

volume = {306},

pages = {121093},

abstract = {Nickel phthalocyanine (NiPc) can be at first glance a compelling catalyst for CO2 reduction reaction (CO2RR) because of its Ni\textendashN4 site. Unfortunately, the pristine NiPc possesses a low catalytic activity resulting from the poor CO2 adsorption and activation capabilities of the electron-deficiency Ni site. Herein, we develop nickel polyphthalocyanine (NiPPc) with extended conjugation to tailor the electronic density at the Ni active site. The enlarged π conjugation of NiPPc evokes the d-electrons localization, increasing the electronic density at the Ni site, which enhances its CO2 adsorption and activation. Consequently, NiPPc supported on carbon nanotubes (NiPPc/CNT) in a flow cell delivers an excellent activity of −300 mA cm−2 for CO2RR with the CO selectivity of 99.8%, which is much higher than that of NiPc dispersed on carbon nanotubes. NiPPc/CNT exhibits an outstanding stability for CO2RR of more than 30 h at a current density of −100 mA cm−2 with an ultrahigh selectivity for CO, exceeding 99.7%. This work showcases a new way of tuning the electronic density of catalytic sites.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Local Growth Mediated by Plasmonic Hot Carriers: Chirality from Achiral Nanocrystals Using Circularly Polarized Light},

author = {L V Besteiro and A Movsesyan and O \'{A}valos-Ovando and S Lee and E Cort\'{e}s and M A Correa-Duarte and Z M Wang and A O Govorov},

url = {https://doi.org/10.1021/acs.nanolett.1c03503},

doi = {10.1021/acs.nanolett.1c03503},

issn = {1530-6984},

year  = {2021},

date = {2021-12-03},

journal = {Nano Letters},

abstract = {Plasmonic nanocrystals and their assemblies are excellent tools to create functional systems, including systems with strong chiral optical responses. Here we study the possibility of growing chiral plasmonic nanocrystals from strictly nonchiral seeds of different types by using circularly polarized light as the chirality-inducing mechanism. We present a novel theoretical methodology that simulates realistic nonlinear and inhomogeneous photogrowth processes in plasmonic nanocrystals, mediated by the excitation of hot carriers that can drive surface chemistry. We show the strongly anisotropic and chiral growth of oriented nanocrystals with lowered symmetry, with the striking feature that such chiral growth can appear even for nanocrystals with subwavelength sizes. Furthermore, we show that the chiral growth of nanocrystals in solution is fundamentally challenging. This work explores new ways of growing monolithic chiral plasmonic nanostructures and can be useful for the development of plasmonic photocatalysis and fabrication technologies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Ligand Engineering in Nickel Phthalocyanine to Boost the Electrocatalytic Reduction of CO2},

author = {K Chen and M Cao and Y Lin and J Fu and H Liao and Y Zhou and H Li and X Qiu and J Hu and X Zheng and M Shakouri and Q Xiao and Y Hu and J Li and J Liu and E Cort\'{e}s and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202111322},

doi = {https://doi.org/10.1002/adfm.202111322},

issn = {1616-301X},

year  = {2021},

date = {2021-12-01},

urldate = {2021-12-01},

journal = {Advanced Functional Materials},

volume = {n/a},

number = {n/a},

pages = {2111322},

abstract = {Abstract Designing and synthesizing efficient molecular catalysts may unlock the great challenge of controlling the CO2 reduction reaction (CO2RR) with molecular precision. Nickel phthalocyanine (NiPc) appears as a promising candidate for this task due to its adjustable Ni active-site. However, the pristine NiPc suffers from poor activity and stability for CO2RR owing to the poor CO2 adsorption and activation at the bare Ni site. Here, a ligand-tuned strategy is developed to enhance the catalytic performance and unveil the ligand effect of NiPc on CO2RR. Theoretical calculations and experimental results indicate that NiPc with electron-donating substituents (hydroxyl or amino) can induce electronic localization at the Ni site which greatly enhances the CO2 adsorption and activation. Employing the optimal catalyst\textemdashan amino-substituted NiPc\textemdashto convert CO2 into CO in a flow cell can achieve an ultrahigh activity and selectivity of 99.8% at current densities up to −400 mA cm−2. This work offers a novel strategy to regulate the electronic structure of active sites by ligand design and discloses the ligand-directed catalysis of the tailored NiPc for highly efficient CO2RR.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Optimizing hydrogen binding on Ru sites with RuCo alloy nanosheets for efficient alkaline hydrogen evolution},

author = {C Cai and K Liu and Y Zhu and P Li and Q Wang and B Liu and S Chen and H Li and L Zhu and H Li and J Fu and Y Chen and E Pensa and J Hu and Y-R Lu and T-S Chan and E Cortes and M Liu},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202113664},

doi = {https://doi.org/10.1002/anie.202113664},

issn = {1433-7851},

year  = {2021},

date = {2021-11-25},

urldate = {2021-11-25},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

abstract = {Ruthenium (Ru)-based catalysts, with considerable performance and desirable cost, become highly concerned candidates to replace platinum (Pt) in alkaline hydrogen evolution reaction (HER). The hydrogen binding at Ru sites (Ru-H) is an important factor limiting the HER activity. Herein, density functional theory (DFT) simulations show that the essence of Ru-H binding energy is the strong interaction between the 4dz 2 orbital of Ru and 1s orbital of H. The charge transfer between Ru sites and substrates (Co and Ni) causes the appropriate downward shift of the 4dz 2 -band center of Ru, which results in a Gibbs free energy of 0.022 eV for H* in RuCo system, much decrease compared to 0.133 eV in pure Ru system. This theoretical prediction has been experimentally confirmed using RuCo alloy nanosheets (RuCo ANSs). They were prepared via fast co-precipitation method followed with a mild electrochemical reduction. Structure characterizations reveal that the Ru atoms are embed into Co substrate as isolated active sites with the planar symmetric and Z-direction asymmetric coordination structure, obtaining an optimal 4dz 2 modulated electronic structure. Hydrogen sensor and temperature program desorption (TPD) tests demonstrate the enhanced Ru-H interactions in RuCo ANSs than pure Ru nanoparticles. As a result, the RuCo ANSs reach an ultra-low overpotential of 10 mV at 10 mA/cm 2 and a Tafel slope of 20.6 mV/dec in 1 M KOH, outperforming that of the commercial Pt/C. This holistic work provides a new insight to promote alkaline HER by optimizing metal-H binding energy of active sites.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Probing the Role of Atomic Defects in Photocatalytic Systems through Photoinduced Enhanced Raman Scattering},

author = {D Glass and R Quesada-Cabrera and S Bardey and P Promdet and R Sapienza and V Keller and S A Maier and V Caps and I P Parkin and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsenergylett.1c01772},

doi = {10.1021/acsenergylett.1c01772},

year  = {2021},

date = {2021-11-10},

journal = {ACS Energy Letters},

pages = {4273-4281},

abstract = {Even in ultralow quantities, oxygen vacancies (VO) drastically impact key properties of metal oxide semiconductors, such as charge transport, surface adsorption, and reactivity, playing central roles in functional materials performance. Current methods used to investigate VO often rely on specialized instrumentation under far from ideal reaction conditions. Hence, the influence of VO generated in situ during catalytic processes has yet to be probed. In this work, we assess in situ extrinsic surface VO formation and lifetime under photocatalytic conditions which we compare to photocatalytic performance. We show for the first time that lifetimes of in situ generated atomic VO play more significant roles in catalysis than their concentration, with strong correlations between longer-lived VO and higher photocatalytic activity. Our results indicate that enhanced photocatalytic efficiency correlates with goldilocks VO concentrations, where VO densities must be just right to encourage carrier transport while avoiding charge carrier trapping.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Metasurface Photoelectrodes for Enhanced Solar Fuel Generation},

author = {L H\"{u}ttenhofer and M Golibrzuch and O Bienek and F J Wendisch and R Lin and M Becherer and I D Sharp and S A Maier and E Cort\'{e}s},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202102877},

doi = {https://doi.org/10.1002/aenm.202102877},

issn = {1614-6832},

year  = {2021},

date = {2021-10-27},

journal = {Advanced Energy Materials},

volume = {11},

number = {46},

pages = {2102877},

abstract = {Abstract Tailoring optical properties in photocatalysts by nanostructuring them can help increase solar light harvesting efficiencies in a wide range of materials. Whereas plasmon resonances are widely employed in metallic catalysts for this purpose, latest advances of nonradiative, dielectric nanophotonics also enable light confinement and enhanced visible light absorption in semiconductors. Here, a design procedure for large-scale nanofabrication of semiconductor photoelectrodes using imprint lithography is developed. Anapole excitations and metasurface lattice resonances are combined to enhance the absorption of the model material, amorphous gallium phosphide (a-GaP), over the visible spectrum. It is shown that cost-effective, high sample throughput is achieved while retaining the precise signature of the engineered photonic states. Photoelectrochemical measurements under hydrogen evolution reaction conditions and sunlight illumination reveal the contributions of the respective resonances and demonstrate an overall photocurrent enhancement of 5.7, compared to a planar film. These results are supported by optical and numerical analysis of single nanodisks and of the upscaled metasurface.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {The Effect of Photoinduced Surface Oxygen Vacancies on the Charge Carrier Dynamics in TiO2 Films},

author = {O E Dagdeviren and D Glass and R Sapienza and E Cort\'{e}s and S A Maier and I P Parkin and P Gr\"{u}tter and R Quesada-Cabrera},

url = {https://doi.org/10.1021/acs.nanolett.1c02853},

doi = {10.1021/acs.nanolett.1c02853},

issn = {1530-6984},

year  = {2021},

date = {2021-09-28},

journal = {Nano Letters},

volume = {21},

number = {19},

pages = {8348-8354},

abstract = {Metal-oxide semiconductors (MOS) are widely utilized for catalytic and photocatalytic applications in which the dynamics of charged carriers (e.g., electrons, holes) play important roles. Under operation conditions, photoinduced surface oxygen vacancies (PI-SOV) can greatly impact the dynamics of charge carriers. However, current knowledge regarding the effect of PI-SOV on the dynamics of hole migration in MOS films, such as titanium dioxide, is solely based upon volume-averaged measurements and/or vacuum conditions. This limits the basic understanding of hole-vacancy interactions, as they are not capable of revealing time-resolved variations during operation. Here, we measured the effect of PI-SOV on the dynamics of hole migration using time-resolved atomic force microscopy. Our findings demonstrate that the time constant associated with hole migration is strongly affected by PI-SOV, in a reversible manner. These results will nucleate an insightful understanding of the physics of hole dynamics and thus enable emerging technologies, facilitated by engineering hole-vacancy interactions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Acoustic Coupling between Plasmonic Nanoantennas: Detection and Directionality of Surface Acoustic Waves},

author = {M Poblet and R Bert\'{e} and H D Boggiano and Y Li and E Cort\'{e}s and G Grinblat and S A Maier and A V Bragas},

url = {https://doi.org/10.1021/acsphotonics.1c00741},

doi = {10.1021/acsphotonics.1c00741},

year  = {2021},

date = {2021-09-17},

urldate = {2021-09-17},

journal = {ACS Photonics},

abstract = {Hypersound waves can be efficient mediators between optical signals at the nanoscale. Having phase velocities several orders of magnitude lower than the speed of light, they propagate with much shorter wavelengths and can be controlled, directed, and even focused in a very small region of space. This work shows how two optical nanoantennas can be coupled through an acoustic wave that propagates with a certain directionality. An “emitter” antenna is first optically excited to generate acoustic coherent phonons that launch surface acoustic waves through the underlying substrate. These waves travel until they are mechanically detected by a “receiver” nanoantenna whose oscillation produces a detectable optical signal. Generation and detection are studied in detail, and new designs are proposed to improve the directionality of the hypersonic surface acoustic wave.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Engineering gallium phosphide nanostructures for efficient nonlinear photonics and enhanced spectroscopies},

author = {G Q Moretti and E Cort\'{e}s and S A Maier and A V Bragas and G Grinblat},

url = {https://doi.org/10.1515/nanoph-2021-0388},

doi = {doi:10.1515/nanoph-2021-0388},

year  = {2021},

date = {2021-09-16},

journal = {Nanophotonics},

number = {000010151520210388},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {In situ surface-enhanced Raman spectroelectrochemistry reveals the molecular conformation of electrolyte additives in Li-ion batteries},

author = {C Zhu and C Fan and E Cort\'{e}s and W Xie},

url = {http://dx.doi.org/10.1039/D1TA04218A},

doi = {10.1039/D1TA04218A},

issn = {2050-7488},

year  = {2021},

date = {2021-08-02},

journal = {Journal of Materials Chemistry A},

volume = {9},

number = {35},

pages = {20024-20031},

abstract = {We report the mechanism of rhodamine B (RhB) acting as an electrolyte additive in Li/graphite cells. We show that the cycle performance and rate capability of graphite are enhanced in carbonate-based electrolytes containing 0.2 wt% RhB. By using silica-encapsulated Au nanoparticles, in situ surface-enhanced Raman spectroscopy (SERS) is applied to study the graphite/electrolyte interface. We find that the adsorption orientation of RhB molecules on the surface of graphite can be modulated by the applied potential: vertical adsorption at higher potentials while horizontal adsorption takes place at lower potentials. This behavior effectively suppresses the electrolyte solvent decomposition, as well as electrode corrosion while improving the Li+ diffusion. This work shows that SERS is a powerful tool for interfacial analysis of battery systems and provides new ideas for rational design of electrolyte additives.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Fermi Level Equilibration at the Metal\textendashMolecule Interface in Plasmonic Systems},

author = {A Stefancu and S Lee and L Zhu and M Liu and R C Lucacel and E Cort\'{e}s and N Leopold},

url = {https://doi.org/10.1021/acs.nanolett.1c02003},

doi = {10.1021/acs.nanolett.1c02003},

issn = {1530-6984},

year  = {2021},

date = {2021-07-22},

urldate = {2021-07-22},

journal = {Nano Letters},

abstract = {We highlight a new metal\textendashmolecule charge transfer process by tuning the Fermi energy of plasmonic silver nanoparticles (AgNPs) in situ. The strong adsorption of halide ions upshifts the Fermi level of AgNPs by up to ∼0.3 eV in the order Cl\textendash \< Br\textendash \< I\textendash, favoring the spontaneous charge transfer to aligned molecular acceptor orbitals until charge neutrality across the interface is achieved. By carefully quantifying, experimentally and theoretically, the Fermi level upshift, we show for the first time that this effect is comparable in energy to different plasmonic effects such as the plasmoelectric effect or hot-carriers production. Moreover, by monitoring in situ the adsorption dynamic of halide ions in different AgNP\textendashmolecule systems, we show for the first time that the catalytic role of halide ions in plasmonic nanostructures depends on the surface affinity of halide ions compared to that of the target molecule.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Self-Constructed Multiple Plasmonic Hotspots on an Individual Fractal to Amplify Broadband Hot Electron Generation},

author = {X Wang and C Liu and C Gao and K Yao and S S M Masouleh and R Bert\'{e} and H Ren and L D S Menezes and E Cort\'{e}s and I C Bicket and H Wang and N Li and Z Zhang and M Li and W Xie and Y Yu and Y Fang and S Zhang and H Xu and A Vomiero and Y Liu and G A Botton and S A Maier and H Liang},

url = {https://doi.org/10.1021/acsnano.1c03218},

doi = {10.1021/acsnano.1c03218},

issn = {1936-0851},

year  = {2021},

date = {2021-06-11},

journal = {ACS Nano},

abstract = {Plasmonic nanoparticles are ideal candidates for hot-electron-assisted applications, but their narrow resonance region and limited hotspot number hindered the energy utilization of broadband solar energy. Inspired by tree branches, we designed and chemically synthesized silver fractals, which enable self-constructed hotspots and multiple plasmonic resonances, extending the broadband generation of hot electrons for better matching with the solar radiation spectrum. We directly revealed the plasmonic origin, the spatial distribution, and the decay dynamics of hot electrons on the single-particle level by using ab initio simulation, dark-field spectroscopy, pump\textendashprobe measurements, and electron energy loss spectroscopy. Our results show that fractals with acute tips and narrow gaps can support broadband resonances (400\textendash1100 nm) and a large number of randomly distributed hotspots, which can provide unpolarized enhanced near field and promote hot electron generation. As a proof-of-concept, hot-electron-triggered dimerization of p-nitropthiophenol and hydrogen production are investigated under various irradiations, and the promoted hot electron generation on fractals was confirmed with significantly improved efficiency.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Tuning the intermediate reaction barriers by a CuPd catalyst to improve the selectivity of CO2 electroreduction to C2 products},

author = {L Zhu and Y Lin and K Liu and E Cort\'{e}s and H Li and J Hu and A Yamaguchi and X Liu and M Miyauchi and J Fu and M Liu},

url = {https://www.sciencedirect.com/science/article/pii/S1872206720637548},

doi = {https://doi.org/10.1016/S1872-2067(20)63754-8},

issn = {1872-2067},

year  = {2021},

date = {2021-05-12},

urldate = {2021-05-12},

journal = {Chinese Journal of Catalysis},

volume = {42},

number = {9},

pages = {1500-1508},

abstract = {Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity. Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon products. However, Cu exhibits an unfavorable activity and selectivity for the generation of C2 products because of the insufficient amount of CO* provided for the C-C coupling. Based on the strong CO2 adsorption and ultrafast reaction kinetics of CO* formation on Pd, an intimate CuPd(100) interface was designed to lower the intermediate reaction barriers and improve the efficiency of C2 product formation. Density functional theory (DFT) calculations showed that the CuPd(100) interface enhanced the CO2 adsorption and decreased the CO2* hydrogenation energy barrier, which was beneficial for the C-C coupling. The potential-determining step (PDS) barrier of CO2 to C2 products on the CuPd(100) interface was 0.61 eV, which was lower than that on Cu(100) (0.72 eV). Encouraged by the DFT calculation results, the CuPd(100) interface catalyst was prepared by a facile chemical solution method and characterized by transmission electron microscopy. CO2 temperature-programmed desorption and gas sensor experiments further confirmed the enhancement of the CO2 adsorption and CO2* hydrogenation ability of the CuPd(100) interface catalyst. Specifically, the obtained CuPd(100) interface catalyst exhibited a C2 Faradaic efficiency of 50.3% ± 1.2% at −1.4 VRHE in 0.1 M KHCO3, which was 2.1 times higher than that of the Cu catalyst (23.6% ± 1.5%). This study provides the basis for the rational design of Cu-based electrocatalysts for the generation of multicarbon products by fine-tuning the intermediate reaction barriers.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Anapole-Assisted Absorption Engineering in Arrays of Coupled Amorphous Gallium Phosphide Nanodisks},

author = {L H\"{u}ttenhofer and A Tittl and L K\"{u}hner and E Cort\'{e}s and S A Maier},

url = {https://doi.org/10.1021/acsphotonics.1c00238},

doi = {10.1021/acsphotonics.1c00238},

year  = {2021},

date = {2021-04-26},

journal = {ACS Photonics},

abstract = {Broadband solar light harvesting plays a crucial role for efficient energy conversion. Anapole excitations and associated absorption engineering in dielectric nanoresonators are a focus of nanophotonic research due to the intricate combination of nonradiating modes and strong electromagnetic field confinement in the underlying material. The arising high field strengths are used for enhanced second-harmonic generation and photocatalysis, where devices require large areas with closely spaced nanoresonators for sizable photonic yields. However, most anapole studies have so far been carried out at the single-particle level, neglecting the influence of anapole\textendashanapole interactions. Here, we present a systematic study of coupling mechanisms in rectangular arrays of amorphous GaP nanodisks that support anapole excitations at 600 nm, which is within the lossy spectral regime of the material. Our experimental findings show that maximum visible light extinction by the array and maximum absorption in the GaP are not achieved by the densest packing of resonators. Counterintuitively, increasing the array periodicities such that collective effects spectrally overlap with the anapole excitation of a single particle leads to an absorption enhancement of up to 300% compared to a single disk. An analysis of coupling in one- and two-dimensional arrays with polarization-dependent measurements and numerical simulations allows us to discriminate between coupling interactions parallel and perpendicular to the polarization axis and evaluate their strengths. Utilizing a multipolar decomposition of excitations in single nanodisks embedded in one-dimensional arrays, we can attribute the coupling to enhanced electric and toroidal dipoles under variation of the interparticle spacing. Our results provide a fundamental understanding of tailored light absorption in coupled anapole resonators and reveal important design guidelines for advanced metasurface approaches in a wide range of energy conversion applications.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Hot electron physics and applications},

author = {L V Besteiro and E Cort\'{e}s and S Ishii and P Narang and R F Oulton},

url = {https://aip.scitation.org/doi/abs/10.1063/5.0050796},

doi = {10.1063/5.0050796},

year  = {2021},

date = {2021-04-19},

journal = {Journal of Applied Physics},

volume = {129},

number = {15},

pages = {150401},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Paired Ru‒O‒Mo ensemble for efficient and stable alkaline hydrogen evolution reaction},

author = {H Li and K Liu and J Fu and K Chen and K Yang and Y Lin and B Yang and Q Wang and H Pan and Z Cai and H Li and M Cao and J Hu and Y-R Lu and T-S Chan and E Cort\'{e}s and A Fratalocchi and M Liu},

url = {http://www.sciencedirect.com/science/article/pii/S2211285521000252},

doi = {https://doi.org/10.1016/j.nanoen.2021.105767},

issn = {2211-2855},

year  = {2021},

date = {2021-04-01},

urldate = {2021-04-01},

journal = {Nano Energy},

volume = {82},

pages = {105767},

abstract = {Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is a promising electrochemical energy conversion strategy. Ruthenium (Ru) is an efficient catalyst with a desirable cost for HER, however, the sluggish H2O dissociation process, due to the low H2O adsorption on its surface, currently hampers the performances of this catalyst in alkaline HER. Herein, we demonstrate that the H2O adsorption improves significantly by the construction of Ru\textendashO\textendashMo sites. We prepared Ru/MoO2 catalysts with Ru\textendashO\textendashMo sites through a facile thermal treatment process and assessed the creation of Ru\textendashO\textendashMo interfaces by transmission electron microscope (TEM) and extended X-ray absorption fine structure (EXAFS). By using Fourier-transform infrared spectroscopy (FTIR) and H2O adsorption tests, we proved Ru\textendashO\textendashMo sites have tenfold stronger H2O adsorption ability than that of Ru catalyst. The catalysts with Ru\textendashO\textendashMo sites exhibited a state-of-the-art overpotential of 16 mV at 10 mA cm\textendash2 in 1 M KOH electrolyte, demonstrating a threefold reduction than the previous bests of Ru (59 mV) and commercial Pt (31 mV) catalysts. We proved the stability of these performances over 40 h without decline. These results could open a new path for designing efficient and stable catalysts.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Challenges in Plasmonic Catalysis},

author = {E Cort\'{e}s and L V Besteiro and A Alabastri and A Baldi and G Tagliabue and A Demetriadou and P Narang},

url = {https://doi.org/10.1021/acsnano.0c08773},

doi = {10.1021/acsnano.0c08773},

issn = {1936-0851},

year  = {2020},

date = {2020-12-22},

urldate = {2020-12-22},

journal = {ACS Nano},

volume = {14},

number = {12},

pages = {16202-16219},

abstract = {The use of nanoplasmonics to control light and heat close to the thermodynamic limit enables exciting opportunities in the field of plasmonic catalysis. The decay of plasmonic excitations creates highly nonequilibrium distributions of hot carriers that can initiate or catalyze reactions through both thermal and nonthermal pathways. In this Perspective, we present the current understanding in the field of plasmonic catalysis, capturing vibrant debates in the literature, and discuss future avenues of exploration to overcome critical bottlenecks. Our Perspective spans first-principles theory and computation of correlated and far-from-equilibrium light\textendashmatter interactions, synthesis of new nanoplasmonic hybrids, and new steady-state and ultrafast spectroscopic probes of interactions in plasmonic catalysis, recognizing the key contributions of each discipline in realizing the promise of plasmonic catalysis. We conclude with our vision for fundamental and technological advances in the field of plasmon-driven chemical reactions in the coming years.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Template Dissolution Interfacial Patterning of Single Colloids for Nanoelectrochemistry and Nanosensing},

author = {J B Lee and H Walker and Y Li and T W Nam and A Rakovich and R Sapienza and Y S Jung and Y S Nam and S A Maier and E Cort\'{e}s},

url = {https://doi.org/10.1021/acsnano.0c09319},

doi = {10.1021/acsnano.0c09319},

issn = {1936-0851},

year  = {2020},

date = {2020-12-03},

urldate = {2020-12-03},

journal = {ACS Nano},

abstract = {Deterministic positioning and assembly of colloidal nanoparticles (NPs) onto substrates is a core requirement and a promising alternative to top-down lithography to create functional nanostructures and nanodevices with intriguing optical, electrical, and catalytic features. Capillary-assisted particle assembly (CAPA) has emerged as an attractive technique to this end, as it allows controlled and selective assembly of a wide variety of NPs onto predefined topographical templates using capillary forces. One critical issue with CAPA, however, lies in its final printing step, where high printing yields are possible only with the use of an adhesive polymer film. To address this problem, we have developed a template dissolution interfacial patterning (TDIP) technique to assemble and print single colloidal AuNP arrays onto various dielectric and conductive substrates in the absence of any adhesion layer, with printing yields higher than 98%. The TDIP approach grants direct access to the interface between the AuNP and the target surface, enabling the use of colloidal AuNPs as building blocks for practical applications. The versatile applicability of TDIP is demonstrated by the creation of direct electrical junctions for electro- and photoelectrochemistry and nanoparticle-on-mirror geometries for single-particle molecular sensing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Core\textendashShell Bimetallic Nanoparticle Trimers for Efficient Light-to-Chemical Energy Conversion},

author = {S Lee and H Hwang and W Lee and D Schebarchov and Y Wy and J Grand and B Augui\'{e} and D H Wi and E Cort\'{e}s and S W Han},

url = {https://doi.org/10.1021/acsenergylett.0c02110},

doi = {10.1021/acsenergylett.0c02110},

year  = {2020},

date = {2020-11-19},

journal = {ACS Energy Letters},

pages = {3881-3890},

abstract = {Incorporation of catalytically active materials into plasmonic metal nanostructures can efficiently merge the reactivity and energy-harvesting abilities of both types of materials for visible light photocatalysis. Herein, we explore the influence of electromagnetic hotspots in the ability of plasmonic core\textendashshell colloidal structures to induce chemical transformations. For this study, we developed a synthetic strategy for the fabrication of Au nanoparticle (NP) trimers in aqueous solution through fine controlled galvanic replacement between Ag nanoprisms and Au precursors. Core\textendashshell Au@M NP trimers with catalytically active metals (M = Pd, Pt) were subsequently synthesized using Au NP trimers as templates. Our experimental and computational results highlight the synergy of geometry and composition in plasmonic catalysts for plasmon-driven chemical reactions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Nanostructured amorphous gallium phosphide on silica for nonlinear and ultrafast nanophotonics},

author = {B Tilmann and G Grinblat and R Bert\'{e} and M \"{O}zcan and V F Kunzelmann and B Nickel and I D Sharp and E Cort\'{e}s and S A Maier and Y Li},

url = {http://dx.doi.org/10.1039/D0NH00461H},

doi = {10.1039/D0NH00461H},

issn = {2055-6756},

year  = {2020},

date = {2020-09-30},

journal = {Nanoscale Horizons},

volume = {5},

number = {11},

pages = {1500-1508},

abstract = {Nanophotonics based on high refractive index dielectrics relies on appreciable contrast between the indices of designed nanostructures and their immediate surrounding, which can be achieved by the growth of thin films on low-index substrates. Here we propose the use of high index amorphous gallium phosphide (a-GaP), fabricated by radio-frequency sputter deposition, on top of a low refractive index glass substrate and thoroughly examine its nanophotonic properties. Spectral ellipsometry of the amorphous material demonstrates the optical properties to be considerably close to crystalline gallium phosphide (c-GaP), with low-loss transparency for wavelengths longer than 650 nm. When nanostructured into nanopatches, the second harmonic (SH) response of an individual a-GaP patch is characterized to be more than two orders of magnitude larger than the as-deposited unstructured film, with an anapole-like resonant behavior. Numerical simulations are in good agreement with the experimental results over a large spectral and geometrical range. Furthermore, by studying individual a-GaP nanopatches through non-degenerate pump\textendashprobe spectroscopy with sub-10 fs pulses, we find a more than 5% ultrafast modulation of the reflectivity that is accompanied by a slower decaying free carrier contribution, caused by absorption. Our investigations reveal a potential for a-GaP as an adequate inexpensive and CMOS-compatible material for nonlinear nanophotonic applications as well as for photocatalysis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electrical control of single-photon emission in highly charged individual colloidal quantum dots},

author = {S Morozov and E L Pensa and A H Khan and A Polovitsyn and E Cort\'{e}s and S A Maier and S Vezzoli and I Moreels and R Sapienza},

url = {https://pubmed.ncbi.nlm.nih.gov/32948584/},

doi = {10.1126/sciadv.abb1821},

issn = {2375-2548},

year  = {2020},

date = {2020-09-18},

urldate = {2020-09-18},

journal = {Sci Adv},

volume = {6},

number = {38},

abstract = {Electron transfer to an individual quantum dot promotes the formation of charged excitons with enhanced recombination pathways and reduced lifetimes. Excitons with only one or two extra charges have been observed and exploited for very efficient lasing or single-quantum dot light-emitting diodes. Here, by room-temperature time-resolved experiments on individual giant-shell CdSe/CdS quantum dots, we show the electrochemical formation of highly charged excitons containing more than 12 electrons and 1 hole. We report the control over intensity blinking, along with a deterministic manipulation of quantum dot photodynamics, with an observed 210-fold increase in the decay rate, accompanied by 12-fold decrease in the emission intensity, while preserving single-photon emission characteristics. These results pave the way for deterministic control over the charge state, and room-temperature decay rate engineering for colloidal quantum dot-based classical and quantum communication technologies.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {In Situ Photothermal Response of Single Gold Nanoparticles through Hyperspectral Imaging Anti-Stokes Thermometry},

author = {M Barella and I L Violi and J Gargiulo and L P Martinez and F Goschin and V Guglielmotti and D Pallarola and S Schl\"{u}cker and M Pilo-Pais and G P Acuna and S A Maier and E Cort\'{e}s and F D Stefani},

url = {https://doi.org/10.1021/acsnano.0c06185},

doi = {10.1021/acsnano.0c06185},

issn = {1936-0851},

year  = {2020},

date = {2020-09-17},

journal = {ACS Nano},

volume = {15},

number = {2},

pages = {2458-2467},

abstract = {Several fields of applications require a reliable characterization of the photothermal response and heat dissipation of nanoscopic systems, which remains a challenging task for both modeling and experimental measurements. Here, we present an implementation of anti-Stokes thermometry that enables the in situ photothermal characterization of individual nanoparticles (NPs) from a single hyperspectral photoluminescence confocal image. The method is label-free, potentially applicable to any NP with detectable anti-Stokes emission, and does not require any prior information about the NP itself or the surrounding media. With it, we first studied the photothermal response of spherical gold NPs of different sizes on glass substrates, immersed in water, and found that heat dissipation is mainly dominated by the water for NPs larger than 50 nm. Then, the role of the substrate was studied by comparing the photothermal response of 80 nm gold NPs on glass with sapphire and graphene, two materials with high thermal conductivity. For a given irradiance level, the NPs reach temperatures 18% lower on sapphire and 24% higher on graphene than on bare glass. The fact that the presence of a highly conductive material such as graphene leads to a poorer thermal dissipation demonstrates that interfacial thermal resistances play a very significant role in nanoscopic systems and emphasize the need for in situ experimental thermometry techniques. The developed method will allow addressing several open questions about the role of temperature in plasmon-assisted applications, especially ones where NPs of arbitrary shapes are present in complex matrixes and environments.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Direct Detection of Optical Forces of Magnetic Nature in Dielectric Nanoantennas},

author = {M Poblet and Y Li and E Cort\'{e}s and S A Maier and G Grinblat and A V Bragas},

url = {https://doi.org/10.1021/acs.nanolett.0c03157},

doi = {10.1021/acs.nanolett.0c03157},

issn = {1530-6984},

year  = {2020},

date = {2020-09-16},

urldate = {2020-09-16},

journal = {Nano Letters},

volume = {20},

number = {10},

pages = {7627-7634},

abstract = {Optical forces on nanostructures are usually characterized by their interaction with the electric field component of the light wave, given that most materials present negligible magnetic response at optical frequencies. This is not the case however of a high-refractive-index dielectric nanoantenna, which has been recently shown to efficiently support both electric and magnetic optical modes. In this work, we use a photoinduced force microscopy configuration to measure optically induced forces produced by a germanium nanoantenna on a surrounding silicon near-field probe. We reveal the spatial distribution, character, and magnitude of the generated forces when exciting the nanoantenna at its anapole state condition. We retrieve optical force maps showing values of up to 20 pN, which are found to be mainly magnetic in nature, according to our numerical simulations. The results of this investigation open new pathways for the study, detection, and generation of magnetic light forces at the nanometer scale.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Efficient ultrafast all-optical modulation in a nonlinear crystalline gallium phosphide nanodisk at the anapole excitation},

author = {G Grinblat and H Zhang and M P Nielsen and L Krivitsky and R Bert\'{e} and Y Li and B Tilmann and E Cort\'{e}s and R F Oulton and A I Kuznetsov and S A Maier},

url = {https://advances.sciencemag.org/content/advances/6/34/eabb3123.full.pdf},

doi = {10.1126/sciadv.abb3123},

year  = {2020},

date = {2020-08-21},

journal = {Science Advances},

volume = {6},

number = {34},

pages = {eabb3123},

abstract = {High\textendashrefractive index nanostructured dielectrics have the ability to locally enhance electromagnetic fields with low losses while presenting high third-order nonlinearities. In this work, we exploit these characteristics to achieve efficient ultrafast all-optical modulation in a crystalline gallium phosphide (GaP) nanoantenna through the optical Kerr effect (OKE) and two-photon absorption (TPA) in the visible/near-infrared range. We show that an individual GaP nanodisk can yield differential reflectivity modulations of up to ~40%, with characteristic modulation times between 14 and 66 fs, when probed at the anapole excitation (AE). Numerical simulations reveal that the AE represents a unique condition where both the OKE and TPA contribute with the same modulation sign, maximizing the response. These findings highly outperform previous reports on sub\textendash100-fs all-optical switching from resonant nanoscale dielectrics, which have demonstrated modulation depths no larger than 0.5%, placing GaP nanoantennas as a promising choice for ultrafast all-optical modulation at the nanometer scale.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Near-Field Spectroscopy of Cylindrical Phonon-Polariton Antennas},

author = {A Mancini and C R Gubbin and R Bert\'{e} and F Martini and A Politi and E Cort\'{e}s and Y Li and S De Liberato and S A Maier},

url = {https://doi.org/10.1021/acsnano.0c02784},

doi = {10.1021/acsnano.0c02784},

issn = {1936-0851},

year  = {2020},

date = {2020-06-12},

urldate = {2020-06-12},

journal = {ACS Nano},

volume = {14},

number = {7},

pages = {8508-8517},

abstract = {Surface phonon polaritons (SPhPs) are hybrid light\textendashmatter states in which light strongly couples to lattice vibrations inside the Reststrahlen band of polar dielectrics at mid-infrared frequencies. Antennas supporting localized surface phonon polaritons (LSPhPs) easily outperform their plasmonic counterparts operating in the visible or near-infrared in terms of field enhancement and confinement thanks to the inherently slower phonon\textendashphonon scattering processes governing SPhP decay. In particular, LSPhP antennas have attracted considerable interest for thermal management at the nanoscale, where the emission strongly diverts from the usual far-field blackbody radiation due to the presence of evanescent waves at the surface. However, far-field measurements cannot shed light on the behavior of antennas in the near-field region. To overcome this limitation, we employ scattering-scanning near-field optical microscopy (sSNOM) to unveil the spectral near-field response of 3C-SiC antenna arrays. We present a detailed description of the behavior of the antenna resonances by comparing far-field and near-field spectra and demonstrate the existence of a mode with no net dipole moment, absent in the far-field spectra, but of importance for applications that exploit the heightened electromagnetic near fields. Furthermore, we investigate the perturbation in the antenna response induced by the presence of the AFM tip, which can be further extended toward situations where for example strong IR emitters couple to LSPhP modes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Determination of Nanoscale Mechanical Properties of Polymers via Plasmonic Nanoantennas},

author = {H D Boggiano and R Berte and A F Scarpettini and E Cortes and S A Maier and A V Bragas},

url = {\<Go to ISI\>://WOS:000542931300008},

doi = {10.1021/acsphotonics.0c00631},

issn = {2330-4022},

year  = {2020},

date = {2020-06-02},

journal = {Acs Photonics},

volume = {7},

number = {6},

pages = {1403-1409},

abstract = {Nanotechnology and the consequent emergence of miniaturized devices are driving the need to improve our understanding of the mechanical properties of a myriad of materials. Here we focus on amorphous polymeric materials and introduce a new way to determine the nanoscale mechanical response of polymeric thin films in the GHz range, using ultrafast optical means. Coupling of the films to plasmonic nanoantennas excited at their vibrational eigenfrequencies allows the extraction of the values of the mechanical moduli as well as the estimation of the glass transition temperature via time-domain measurements, here demonstrated for PMMA films. This nanoscale method can be extended to the determination of mechanical and elastic properties of a wide range of spatially strongly confined materials.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Anapole Excitations in Oxygen-Vacancy-Rich TiO2\textendashx Nanoresonators: Tuning the Absorption for Photocatalysis in the Visible Spectrum},

author = {L H\"{u}ttenhofer and F Eckmann and A Lauri and J Cambiasso and E Pensa and Y Li and E Cort\'{e}s and I D Sharp and S A Maier},

url = {https://doi.org/10.1021/acsnano.9b09987},

doi = {10.1021/acsnano.9b09987},

issn = {1936-0851},

year  = {2020},

date = {2020-02-25},

journal = {ACS Nano},

volume = {14},

number = {2},

pages = {2456-2464},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Towards Reliable and Quantitative Surface-Enhanced Raman Scattering (SERS): From Key Parameters to Good Analytical Practice},

author = {S E J Bell and G Charron and E Cort\'{e}s and J Kneipp and De La M L Chapelle and J Langer and M Proch\'{a}zka and V Tran and S Schl\"{u}cker},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201908154},

doi = {10.1002/anie.201908154},

issn = {1433-7851},

year  = {2019},

date = {2019-10-07},

urldate = {2019-10-07},

journal = {Angewandte Chemie International Edition},

volume = {59},

number = {14},

pages = {5454-5462},

abstract = {Abstract Experimental results obtained in different laboratories world-wide by researchers using surface-enhanced Raman scattering (SERS) can differ significantly. We, an international team of scientists with long-standing expertise in SERS, address this issue from our perspective by presenting considerations on reliable and quantitative SERS. The central idea of this joint effort is to highlight key parameters and pitfalls that are often encountered in the literature. To that end, we provide here a series of recommendations on: a) the characterization of solid and colloidal SERS substrates by correlative electron and optical microscopy and spectroscopy, b) on the determination of the SERS enhancement factor (EF), including suitable Raman reporter/probe molecules, and finally on c) good analytical practice. We hope that both newcomers and specialists will benefit from these recommendations to increase the inter-laboratory comparability of experimental SERS results and further establish SERS as an analytical tool.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Particle-in-a-Frame Nanostructures with Interior Nanogaps},

author = {S Lee and J Kim and H Yang and E Cort\'{e}s and S Kang and S W Han},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.201908291},

doi = {https://doi.org/10.1002/anie.201908291},

issn = {1433-7851},

year  = {2019},

date = {2019-09-03},

journal = {Angewandte Chemie International Edition},

volume = {58},

number = {44},

pages = {15890-15894},

abstract = {Abstract Designing plasmonic hollow colloids with small interior nanogaps would allow structural properties to be exploited that are normally linked to an ensemble of particles but within a single nanoparticle. Now, a synthetic approach for constructing a new class of frame nanostructures is presented. Fine control over the galvanic replacement reaction of Ag nanoprisms with Au precursors gave unprecedented Au particle-in-a-frame nanostructures with well-defined sub-2 nm interior nanogaps. The prepared nanostructures exhibited superior performance in applications, such as plasmonic sensing and surface-enhanced Raman scattering, over their solid nanostructure and nanoframe counterparts. This highlights the benefit of their interior hot spots, which can highly promote and maximize the electric field confinement within a single nanostructure.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {From Optical to Chemical Hot Spots in Plasmonics},

author = {J Gargiulo and R Bert\'{e} and Y Li and S A Maier and E Cort\'{e}s},

url = {https://doi.org/10.1021/acs.accounts.9b00234},

doi = {10.1021/acs.accounts.9b00234},

issn = {0001-4842},

year  = {2019},

date = {2019-08-20},

journal = {Accounts of Chemical Research},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{,

title = {Spectral Screening of the Energy of Hot Holes over a Particle Plasmon Resonance},

author = {E Pensa and J Gargiulo and A Lauri and S Schl\"{u}cker and E Cort\'{e}s and S A Maier},

url = {https://doi.org/10.1021/acs.nanolett.8b04950},

doi = {10.1021/acs.nanolett.8b04950},

issn = {1530-6984},

year  = {2019},

date = {2019-03-13},

journal = {Nano Letters},

volume = {19},

number = {3},

pages = {1867-1874},

keywords = {},

pubstate = {published},

tppubtype = {article}

}