Publications

@article{nokey,

title = {Strong Induced Circular Dichroism in a Hybrid Lead-Halide Semiconductor Using Chiral Amino Acids for Crystallite Surface Functionalization},

author = {M W Heindl and T Kodalle and N Fehn and L K Reb and S Liu and C Harder and M Abdelsamie and L Eyre and I D Sharp and S V Roth and P M\"{u}ller-Buschbaum and A Kartouzian and C M Sutter-Fella and F Deschler},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202200204},

doi = {https://doi.org/10.1002/adom.202200204},

issn = {2195-1071},

year  = {2022},

date = {2022-06-17},

journal = {Advanced Optical Materials},

volume = {n/a},

number = {n/a},

pages = {2200204},

abstract = {Abstract Chirality is a desired property in functional semiconductors for optoelectronic, catalytic, and spintronic applications. Here, introducing enantiomerically-pure 3-aminobutyric acid (3-ABA) into thin films of the 1D semiconductor dimethylammonium lead iodide (DMAPbI3) is found to result in strong circular dichroism (CD) in the optical absorption. X-ray diffraction and grazing incidence small angle X-ray scattering (GISAXS) are applied to gain molecular-scale insights into the chirality transfer mechanism, which is attributed to a chiral surface modification of DMAPbI3 crystallites. This study demonstrates that the CD signal strength can be controlled by the amino-acid content relative to the crystallite surface area. The CD intensity is tuned by the composition of the precursor solution and the spin-coating time, thereby achieving anisotropy factors (gabs) as high as 1.75 × 10\textendash2. Grazing incidence wide angle scattering reveals strong preferential ordering that can be suppressed via tailored synthesis conditions. Different contributions to the chiroptical properties are resolved by a detailed analysis of the CD signal utilizing an approach based on the Mueller matrix model. This report of a novel class of chiral hybrid semiconductors with precise control over their optical activity presents a promising approach for the design of circularly polarized light detectors and emitters.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Covalent Organic Framework Nanoplates Enable Solution-Processed Crystalline Nanofilms for Photoelectrochemical Hydrogen Evolution},

author = {L Yao and A Rodr\'{i}guez-Camargo and M Xia and D M\"{u}cke and R Guntermann and Y Liu and L Grunenberg and A Jim\'{e}nez-Solano and S T Emmerling and V Duppel and K Sivula and T Bein and H Qi and U Kaiser and M Gr\"{a}tzel and B V Lotsch},

url = {https://doi.org/10.1021/jacs.2c01433},

doi = {10.1021/jacs.2c01433},

issn = {0002-7863},

year  = {2022},

date = {2022-06-15},

journal = {Journal of the American Chemical Society},

volume = {144},

number = {23},

pages = {10291-10300},

abstract = {As covalent organic frameworks (COFs) are coming of age, the lack of effective approaches to achieve crystalline and centimeter-scale-homogeneous COF films remains a significant bottleneck toward advancing the application of COFs in optoelectronic devices. Here, we present the synthesis of colloidal COF nanoplates, with lateral sizes of ∼200 nm and average heights of 35 nm, and their utilization as photocathodes for solar hydrogen evolution. The resulting COF nanoplate colloid exhibits a unimodal particle-size distribution and an exceptional colloidal stability without showing agglomeration after storage for 10 months and enables smooth, homogeneous, and thickness-tunable COF nanofilms via spin coating. Photoelectrodes comprising COF nanofilms were fabricated for photoelectrochemical (PEC) solar-to-hydrogen conversion. By rationally designing multicomponent photoelectrode architectures including a polymer donor/COF heterojunction and a hole-transport layer, charge recombination in COFs is mitigated, resulting in a significantly increased photocurrent density and an extremely positive onset potential for PEC hydrogen evolution (over +1 V against the reversible hydrogen electrode), among the best of classical semiconductor-based photocathodes. This work thus paves the way toward fabricating solution-processed large-scale COF nanofilms and heterojunction architectures and their use in solar-energy-conversion devices.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Radial bound states in the continuum for polarization-invariant nanophotonics},

author = {L K\"{u}hner and L Sortino and R Bert\'{e} and J Wang and H Ren and S A Maier and Y S Kivshar and A Tittl},

url = {https://arxiv.org/abs/2206.05206},

doi = {https://doi.org/10.48550/arXiv.2206.05206},

year  = {2022},

date = {2022-06-10},

journal = {arXiv preprint arXiv:2206.05206},

abstract = {All-dielectric nanophotonics underpinned by bound states in the continuum (BICs) have demonstrated breakthrough applications in nanoscale light manipulation, frequency conversion and optical sensing. Leading BIC implementations range from isolated nanoantennas with localized electromagnetic fields to symmetry-protected metasurfaces with controllable resonance quality (Q) factors. However, they either require structured light illumination with complex beamshaping optics or large, fabrication-intense arrays of polarization-sensitive unit cells, hindering tailored nanophotonic applications and on-chip integration. Here, we introduce radial quasi bound states in the continuum (rBICs) as a new class of radially distributed electromagnetic modes controlled by structural asymmetry in a ring of dielectric rod pair resonators. The rBIC platform provides polarization-invariant and tunable high-Q resonances with strongly enhanced near-fields in an ultracompact footprint as low as 2 μm2. We demonstrate rBIC realizations in the visible for sensitive biomolecular detection and enhanced second-harmonic generation from monolayers of transition metal dichalcogenides, opening new perspectives for compact, spectrally selective, and polarization-invariant metadevices for multi-functional light-matter coupling, multiplexed sensing, and high-density on-chip photonics.},

keywords = {Foundry Inorganic, Molecularly-Functionalized},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {From Free-Energy Profiles to Activation Free Energies},

author = {J C Dietschreit and D J Diestler and A Hulm and C Ochsenfeld and R G\'{o}mez-Bombarelli},

url = {https://arxiv.org/abs/2206.02893},

doi = {https://doi.org/10.48550/arXiv.2206.02893},

year  = {2022},

date = {2022-06-06},

journal = {arXiv preprint arXiv:2206.02893},

abstract = {Given a chemical reaction going from reactant (R) to the product (P) on a potential energy surface (PES) and a collective variable (CV) that discriminates between R and P, one can define a free-energy profile (FEP) as the logarithm of the marginal Boltzmann distribution of the CV. The FEP is not a true free energy, however, it is common to treat the FEP as the free-energy analog of the minimum energy path on the PES and to take the activation free energy, ΔF‡RP, as the difference between the maximum of the FEP at the transition state and the minimum at R. We show that this approximation can result in large errors. Since the FEP depends on the CV, it is therefore not unique, and different, discriminating CVs can yield different activation free energies for the same reaction. We derive an exact expression for the activation free energy that avoids this ambiguity with respect to the choice of CV. We find ΔF‡RP to be a combination of the probability of the system being in the reactant state, the probability density at the transition state surface, and the thermal de~Broglie wavelength associated with the transition from R to P. We then evaluate the activation free energies based on our formalism for simple analytic models and realistic chemical systems. The analytic models show that the widespread FEP-based approximation applies only at low temperatures for CVs for which the effective mass of the associated pseudo-particle is small. Most chemical reactions of practical interest involve polyatomic molecules with complex, high-dimensional PES that cannot be treated analytically and pose the added challenge of choosing a good CV, typically through heuristics. We study the influence of the choice of CV and find that, while the reaction free energy is largely unaffected, ΔF‡RP is quite sensitive.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Metasurface-Enhanced Infrared Spectroscopy: An Abundance of Materials and Functionalities},

author = {A John-Herpin and A Tittl and L K\"{u}hner and F Richter and S H Huang and G Shvets and S-H Oh and H Altug},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202110163},

doi = {https://doi.org/10.1002/adma.202110163},

issn = {0935-9648},

year  = {2022},

date = {2022-05-31},

journal = {Advanced Materials},

volume = {n/a},

number = {n/a},

pages = {2110163},

abstract = {Abstract Infrared (IR) spectroscopy provides unique information on the composition and dynamics of biochemical systems by resolving the characteristic absorption fingerprints of their constituent molecules. Based on this inherent chemical specificity and the capability for label-free, non-invasive, and real-time detection, IR spectroscopy approaches have unlocked a plethora of breakthrough application perspectives for fields ranging from environmental monitoring and defense to chemical analysis and medical diagnostics. Nanophotonics has played a crucial role for pushing the sensitivity limits of traditional far-field spectroscopy by using resonant nanostructures to focus the incident light into nanoscale hot-spots of the electromagnetic field, greatly enhancing light-matter interaction. Metasurfaces composed of regular arrangements of such resonators further increase the design space for tailoring this nanoscale light control both spectrally and spatially, which has established them as an invaluable toolkit for surface-enhanced spectroscopy. Starting from the fundamental concepts of metasurface-enhanced IR spectroscopy, we showcase a broad palette of resonator geometries, materials and arrangements for realizing highly sensitive metadevices, with a special focus on emerging systems such as phononic and 2D van der Waals materials, and integration with waveguides for lab-on-a-chip devices. Furthermore, we will highlight some advanced sensor functionalities of metasurface-based IR spectroscopy, including multiresonance, tunability, dielectrophoresis, live cell sensing, and machine-learning-aided analysis. This article is protected by copyright. All rights reserved},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Operando Study of Structure Degradation in Solid-State Dye-Sensitized Solar Cells with a TiO2 Photoanode Having Ordered Mesopore Arrays},

author = {N Li and R Guo and A L Oechsle and M A Reus and S Liang and L Song and K Wang and D Yang and F Allegretti and A Kumar and M Nuber and J Berger and S Bernstorff and H Iglev and J Hauer and R A Fischer and J V Barth and P M\"{u}ller-Buschbaum},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202200373},

doi = {https://doi.org/10.1002/solr.202200373},

issn = {2367-198X},

year  = {2022},

date = {2022-05-31},

journal = {Solar RRL},

volume = {n/a},

number = {n/a},

pages = {2200373},

abstract = {Via operando grazing-incidence small-angle X-ray scattering, the degradation mechanisms of solid-state dye-sensitized solar cells (ssDSSCs) using two types of ordered mesoporous TiO2 scaffolds with different pore sizes, and an exemplary dye D205, are investigated. The temporal evolution of the inner morphology shows a strong impact on device performance. The photoinduced dye aggregation on the TiO2 surface leads to an increase in the domain radius but a decreased spatial order of the photoactive layer during the burn-in stage. This dye aggregation on the TiO2 surface causes the short-circuit current density loss, which plays a major role in the power conversion efficiency decay. Finally, it is found that a larger surface area in the small-pore sample yields a faster short-circuit current density decay as compared with the big-pore sample. Therefore, a control of dye aggregation and the pore size of TiO2 photoelectrodes is crucial for the stability of TiO2-based ssDSSCs.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Advances in nano-and microscale NMR spectroscopy using diamond quantum sensors},

author = {R D Allert and K D Briegel and D B Bucher},

url = {https://arxiv.org/abs/2205.12178},

doi = {https://doi.org/10.48550/arXiv.2205.12178},

year  = {2022},

date = {2022-05-24},

journal = {arXiv preprint arXiv:2205.12178},

abstract = {Quantum technologies have seen a rapid developmental surge over the last couple of years. Though often overshadowed by quantum computation, quantum sensors show tremendous potential for widespread applications in chemistry and biology. One system stands out in particular: the nitrogen-vacancy (NV) center in diamond, an atomic-sized sensor allowing the detection of nuclear magnetic resonance (NMR) signals at unprecedented length scales down to a single proton. In this article, we review the fundamentals of NV center-based quantum sensing and its distinct impact on nano- to microscale NMR spectroscopy. Furthermore, we highlight and discuss possible future applications of this novel technology ranging from energy research, material science, or single-cell biology, but also associated challenges of these rapidly developing NMR sensors.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Understanding Carotenoid Dynamics via the Vibronic Energy Relaxation Approach},

author = {V \v{S}ebel\'{i}k and C D P Duffy and E Keil and T Pol\'{i}vka and J Hauer},

url = {https://doi.org/10.1021/acs.jpcb.2c00996},

doi = {10.1021/acs.jpcb.2c00996},

issn = {1520-6106},

year  = {2022},

date = {2022-05-24},

journal = {The Journal of Physical Chemistry B},

abstract = {Carotenoids are an integral part of natural photosynthetic complexes, with tasks ranging from light harvesting to photoprotection. Their underlying energy deactivation network of optically dark and bright excited states is extremely efficient: after excitation of light with up to 2.5 eV of photon energy, the system relaxes back to ground state on a time scale of a few picoseconds. In this article, we summarize how a model based on the vibrational energy relaxation approach (VERA) explains the main characteristics of relaxation dynamics after one-photon excitation with special emphasis on the so-called S* state. Lineshapes after two-photon excitation are beyond the current model of VERA. We outline this future line of research in our article. In terms of experimental method development, we discuss which techniques are needed to better describe energy dissipation effects in carotenoids and within the first solvation shell.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Capabilities and limitations of rotating disk electrodes versus membrane electrode assemblies in the investigation of electrocatalysts},

author = {T Lazaridis and B M St\"{u}hmeier and H A Gasteiger and H A El-Sayed},

url = {https://doi.org/10.1038/s41929-022-00776-5},

doi = {10.1038/s41929-022-00776-5},

issn = {2520-1158},

year  = {2022},

date = {2022-05-23},

journal = {Nature Catalysis},

volume = {5},

number = {5},

pages = {363-373},

abstract = {Cost-competitive fuel cells and water electrolysers require highly efficient electrocatalysts for the respective reactions of hydrogen oxidation and evolution, and oxygen evolution and reduction. Electrocatalyst activity and durability are commonly assessed using rotating disk electrodes (RDEs) or membrane electrode assemblies (MEAs). RDEs provide a quick and widely accessible testing tool, whereas MEA testing is more complex but closely resembles the actual application. Although both experimental set-ups allow investigation of the same reactions, there are scientific questions that cannot be answered by the RDE technique. In this Perspective, we scrutinize protocols widely used to determine the activity and durability of electrocatalysts, and highlight discrepancies in the results obtained using RDEs and MEAs. We discuss where the use of RDEs is appropriate and, conversely, where it leads to erroneous interpretations. Ultimately, we show that many of the current challenges for hydrogen and oxygen electrocatalysts require MEA testing and advocate for its greater adoption in the early stages of electrocatalyst development.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Effect of Solvent Vapor Annealing on Diblock Copolymer-Templated Mesoporous Si/Ge/C Thin Films: Implications for Li-Ion Batteries},

author = {C L Weindl and C E Fajman and M A Giebel and K S Wienhold and S Yin and T Tian and C Geiger and L P Kreuzer and M Schwartzkopf and S V Roth and T F F\"{a}ssler and P M\"{u}ller-Buschbaum},

url = {https://doi.org/10.1021/acsanm.2c01191},

doi = {10.1021/acsanm.2c01191},

year  = {2022},

date = {2022-05-17},

journal = {ACS Applied Nano Materials},

volume = {5},

number = {5},

pages = {7278-7287},

abstract = {Although amphiphilic diblock copolymer templating of inorganic materials such as TiO2 is already well investigated, sol\textendashgel synthesis routines for porous silicon and germanium are relatively rare. Therefore, especially in the field of Li-ion batteries, novel synthesis routines with the possibility to tune the silicon and germanium ratio and the morphology in the nanometer regime are of high interest. Here, we demonstrate a synthesis method that allows a change of morphology and elemental composition with minimal effort. We evidence a morphological transformation in the nanometer regime with real space (scanning electron microscopy) and complementary reciprocal space analysis methods (grazing-incidence small-angle X-ray scattering). Although energy-dispersive X-ray spectroscopy (EDS) reveals a considerable amount of oxygen in the thin film, crystalline Ge in the bulk is detected with powder X-ray diffraction (PXRD) and Raman spectroscopy. Due to the system’s simplicity, chemical mass production options such as roll-to-roll or slot-die printing can also be considered high-yield methods compared to standard synthesis routines.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Gold\textendashrhodium nanoflowers for the plasmon enhanced ethanol electrooxidation under visible light for tuning the activity and selectivity},

author = {M P S Rodrigues and A H B Dourado and K Krischer and S I C Torresi},

url = {https://www.sciencedirect.com/science/article/pii/S0013468622006016},

doi = {https://doi.org/10.1016/j.electacta.2022.140439},

issn = {0013-4686},

year  = {2022},

date = {2022-05-12},

journal = {Electrochimica Acta},

volume = {420},

pages = {140439},

abstract = {Direct ethanol fuel cells (DEFCs) are a promising power source, but the low selectivity to ethanol complete oxidation is still challenging. The localized surface plasmon resonance (LSPR) excitation has been reported to accelerate and drive several chemical reactions, including the ethanol oxidation reaction (EOR), coming as a strategy to improve catalysts performance. Nonetheless, metallic nanoparticles (NPs) that present the LSPR excitation in the visible range are known for leading to the incomplete oxidation of ethanol. Thus, we report here the application of gold-rhodium nanoflowers (Au@Rh NFs) towards the plasmon-enhanced EOR. These hybrid materials consist of a Au spherical nucleus covered by Rh branches shell, combining plasmonic and catalytic properties. Firstly, the Au@Rh NFs metallic ratio was investigated in dark conditions to obtain an optimal catalyst. Experiments were also performed under light irradiation. Our data demonstrated an improvement of 352% in current density and 36% in selectivity to complete ethanol oxidation under 533 nm laser incidence. Moreover, the current density showed a linear increase with the laser power density, indicating a photochemical effect and thus enhancement due to the LSPR properties.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Inverse Multislice Ptychography by Layer-wise Optimisation and Sparse Matrix Decomposition},

author = {A Bangun and O Melnyk and B M\"{a}rz and B Diederichs and A Clausen and D Weber and F Filbir and K M\"{u}ller-Caspary},

url = {https://arxiv.org/abs/2205.03902},

doi = {https://doi.org/10.48550/arXiv.2205.03902},

year  = {2022},

date = {2022-05-08},

journal = {arXiv preprint arXiv:2205.03902},

abstract = {We propose algorithms based on an optimisation method for inverse multislice ptychography in, e.g. electron microscopy. The multislice method is widely used to model the interaction between relativistic electrons and thick specimens. Since only the intensity of diffraction patterns can be recorded, the challenge in applying inverse multislice ptychography is to uniquely reconstruct the electrostatic potential in each slice up to some ambiguities. In this conceptual study, we show that a unique separation of atomic layers for simulated data is possible when considering a low acceleration voltage. We also introduce an adaptation for estimating the illuminating probe. For the sake of practical application, we finally present slice reconstructions using experimental 4D scanning transmission electron microscopy (STEM) data.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Solution-based synthesis of wafer-scale epitaxial BiVO4 thin films exhibiting high structural and optoelectronic quality},

author = {V F Kunzelmann and C-M Jiang and I Ihrke and E Sirotti and T Rieth and A Henning and J Eichhorn and I D Sharp},

url = {http://dx.doi.org/10.1039/D1TA10732A},

doi = {10.1039/D1TA10732A},

issn = {2050-7488},

year  = {2022},

date = {2022-04-22},

journal = {Journal of Materials Chemistry A},

abstract = {We demonstrate a facile approach to solution-based synthesis of wafer-scale epitaxial bismuth vanadate (BiVO4) thin films by spin-coating on yttria-stabilized zirconia. Epitaxial growth proceeds via solid-state transformation of initially formed polycrystalline films, driven by interface energy minimization. The (010)-oriented BiVO4 films are smooth and compact, possessing remarkably high structural quality across complete 2′′ wafers. Optical absorption is characterized by a sharp onset with a low sub-band gap response, confirming that the structural order of the films results in correspondingly high optoelectronic quality. This combination of structural and optoelectronic quality enables measurements that reveal a strong optical anisotropy of BiVO4, which leads to significantly increased in-plane optical constants near the fundamental band edge that are of particular importance for maximizing light harvesting in semiconductor photoanodes. Temperature-dependent transport measurements confirm a thermally activated hopping barrier of ∼570 meV, consistent with small electron polaron conduction. This simple approach for synthesis of high-quality epitaxial BiVO4, without the need for complex deposition equipment, enables a broadly accessible materials base to accelerate research aimed at understanding and optimizing photoelectrochemical energy conversion mechanisms.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Revealing the Nature of Active Sites on Pt\textendashGd and Pt\textendashPr Alloys during the Oxygen Reduction Reaction},

author = {R M Kluge and E Psaltis and R W Haid and S Hou and T O Schmidt and O Schneider and B Garlyyev and F Calle-Vallejo and A S Bandarenka},

url = {https://doi.org/10.1021/acsami.2c03604},

doi = {10.1021/acsami.2c03604},

issn = {1944-8244},

year  = {2022},

date = {2022-04-20},

journal = {ACS Applied Materials \& Interfaces},

volume = {14},

number = {17},

pages = {19604-19613},

abstract = {For large-scale applications of hydrogen fuel cells, the sluggish kinetics of the oxygen reduction reaction (ORR) have to be overcome. So far, only platinum (Pt)-group catalysts have shown adequate performance and stability. A well-known approach to increase the efficiency and decrease the Pt loading is to alloy Pt with other metals. Still, for catalyst optimization, the nature of the active sites is crucial. In this work, electrochemical scanning tunneling microscopy (EC-STM) is used to probe the ORR active areas on Pt5Gd and Pt5Pr in acidic media under reaction conditions. The technique detects localized fluctuations in the EC-STM signal, which indicates differences in the local activity. The in situ experiments, supported by coordination\textendashactivity plots based on density functional theory calculations, show that the compressed Pt\textendashlanthanide (111) terraces contribute the most to the overall activity. Sites with higher coordination, as found at the bottom of step edges or concavities, remain relatively inactive. Sites of lower coordination, as found near the top of step edges, show higher activity, presumably due to an interplay of strain and steric hindrance effects. These findings should be vital in designing nanostructured Pt\textendashlanthanide electrocatalysts.},

keywords = {Foundry Inorganic},

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 = {Foundry Inorganic, Molecularly-Functionalized},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Li+ Conductivity of Space Charge Layers Formed at Electrified Interfaces Between a Model Solid-State Electrolyte and Blocking Au-Electrodes},

author = {L Katzenmeier and L Carstensen and A S Bandarenka},

url = {https://doi.org/10.1021/acsami.2c00650},

doi = {10.1021/acsami.2c00650},

issn = {1944-8244},

year  = {2022},

date = {2022-04-06},

journal = {ACS Applied Materials \& Interfaces},

volume = {14},

number = {13},

pages = {15811-15817},

abstract = {The formation of space charge layers in solid-state ion conductors has been investigated as early as the 1980s. With the advent of all-solid-state batteries as an alternative to traditional Li-ion batteries, possibly improving performance and safety, the phenomenon of space charge formation caught the attention of researchers as a possible origin for the observed high interfacial resistance. Following classical space charge theory, such high resistances result from the formation of the depletion layers. These layers of up to hundreds of nanometers in thickness are almost free of mobile cations. With the prediction of a Debye-like screening effect, the thickness of the depletion layer is expected to scale with the square root of the absolute temperature. In this work, we studied the temperature dependence of the depletion layer properties in model solid Ohara LICGC Li+ conducting electrolytes using electrochemical impedance spectroscopy. We show that the activation energy inside the depletion layer increases to ca 0.42 eV compared to ca 0.39 eV in the bulk electrolyte. Moreover, the proportionality between temperature and depletion layer thickness, correlating to the Debye length, is tested and validated.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {High-Throughput Fabrication of Triangular Nanogap Arrays for Surface-Enhanced Raman Spectroscopy},

author = {S Luo and A Mancini and F Wang and J Liu and S A Maier and J C De Mello},

url = {https://doi.org/10.1021/acsnano.1c09930},

doi = {10.1021/acsnano.1c09930},

issn = {1936-0851},

year  = {2022},

date = {2022-04-05},

journal = {ACS Nano},

abstract = {Squeezing light into nanometer-sized metallic nanogaps can generate extremely high near-field intensities, resulting in dramatically enhanced absorption, emission, and Raman scattering of target molecules embedded within the gaps. However, the scarcity of low-cost, high-throughput, and reproducible nanogap fabrication methods offering precise control over the gap size is a continuing obstacle to practical applications. Using a combination of molecular self-assembly, colloidal nanosphere lithography, and physical peeling, we report here a high-throughput method for fabricating large-area arrays of triangular nanogaps that allow the gap width to be tuned from ∼10 to ∼3 nm. The nanogap arrays function as high-performance substrates for surface-enhanced Raman spectroscopy (SERS), with measured enhancement factors as high as 108 relative to a thin gold film. Using the nanogap arrays, methylene blue dye molecules can be detected at concentrations as low as 1 pM, while adenine biomolecules can be detected down to 100 pM. We further show that it is possible to achieve sensitive SERS detection on binary-metal nanogap arrays containing gold and platinum, potentially extending SERS detection to the investigation of reactive species at platinum-based catalytic and electrochemical surfaces.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Transversal Halide Motion Intensifies Band-To-Band Transitions in Halide Perovskites},

author = {C Gehrmann and S Caicedo-D\'{a}vila and X Zhu and D A Egger},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/advs.202200706},

doi = {https://doi.org/10.1002/advs.202200706},

issn = {2198-3844},

year  = {2022},

date = {2022-04-04},

journal = {Advanced Science},

volume = {n/a},

number = {n/a},

pages = {2200706},

abstract = {Abstract Despite their puzzling vibrational characteristics that include strong signatures of anharmonicity and thermal disorder already around room temperature, halide perovskites (HaPs) exhibit favorable optoelectronic properties for applications in photovoltaics and beyond. Whether these vibrational properties are advantageous or detrimental to their optoelectronic properties remains, however, an important open question. Here, this issue is addressed by investigation of the finite-temperature optoelectronic properties in the prototypical cubic CsPbBr3, using first-principles molecular dynamics based on density-functional theory. It is shown that the dynamic flexibility associated with HaPs enables the so-called transversality, which manifests as a preference for large halide displacements perpendicular to the Pb-Br-Pb bonding axis. The authors find that transversality is concurrent with vibrational anharmonicity and leads to a rapid rise in the joint density of states, which is favorable for photovoltaics since this implies sharp optical absorption profiles. These findings are contrasted to the case of PbTe, a material that shares several key properties with CsPbBr3 but cannot exhibit any transversality and, hence, is found to exhibit much wider band-edge distributions. The authors conclude that the dynamic structural flexibility in HaPs and their unusual vibrational characteristics might not just be a mere coincidence, but play active roles in establishing their favorable optoelectronic properties.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Time-Resolved Orientation and Phase Analysis of Lead Halide Perovskite Film Annealing Probed by In Situ GIWAXS},

author = {M A Reus and L K Reb and A F Weinzierl and C L Weindl and R Guo and T Xiao and M Schwartzkopf and A Chumakov and S V Roth and P M\"{u}ller-Buschbaum},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adom.202102722},

doi = {https://doi.org/10.1002/adom.202102722},

issn = {2195-1071},

year  = {2022},

date = {2022-04-03},

journal = {Advanced Optical Materials},

volume = {n/a},

number = {n/a},

pages = {2102722},

abstract = {Abstract Scalable thin-film deposition methods are increasingly important for hybrid lead halide perovskite thin films. Understanding the structure evolution during non-equilibrium processes helps to find suitable materials and processing parameters to produce films with well-performing optoelectronic properties. Here, spin-cast and slot-die coated bilayers of lead iodide (PbI2) and methylammonium iodide (MAI) are investigated by in situ grazing-incidence wide-angle X-ray scattering during the thermal annealing process, which converts the bilayer into methylammonium lead iodide (MAPI). Photoluminescence (PL) and UV/Vis measurements show increasing crystallinity during the annealing process and a slight PL red-shift of the spin-cast film, attributed to crystallite coalescence that is not prominent for the slot-die coated film. The disintegration of the solvent-precursor complex (MA)2(Pb3I8) ⋅ 2 DMSO and conversion into perovskite are followed in situ and differences in the morphology and time evolution are observed. In both, spin-cast and slot-die coated thin-films, the isotropic orientation is dominant, however, in the slot-die coated films, the perovskite crystallites have an additional face-on orientation ((110) parallel to substrate) that is not detected in spin-cast films. An Avrami model is applied for the perovskite crystal growth that indicates reduced dimensionality of the growth for the printed thin films.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Selectivity Trends and Role of Adsorbate-Adsorbate Interactions in CO Hydrogenation on Rhodium Catalysts},

author = {M Deimel and H Prats and M Seibt and K Reuter and M Andersen},

url = {https://arxiv.org/abs/2203.15746},

doi = {https://doi.org/10.48550/arXiv.2203.15746},

year  = {2022},

date = {2022-03-29},

journal = {arXiv preprint arXiv:2203.15746},

abstract = {Predictive-quality computational modeling of heterogeneously catalyzed reactions has emerged as an important tool for the analysis and assessment of activity and activity trends. In contrast, more subtle selectivities and selectivity trends still pose a significant challenge to prevalent microkinetic modeling approaches that typically employ a mean-field approximation (MFA). Here, we focus on CO hydrogenation on Rh catalysts with the possible products methane, acetaldehyde, ethanol and water. This reaction has already been subject to a number of experimental and theoretical studies with conflicting views on the factors controlling activity and selectivity towards the more valuable higher oxygenates. Using accelerated first-principles kinetic Monte Carlo (KMC) simulations and explicitly and systematically accounting for adsorbate-adsorbate interactions through a cluster expansion approach, we model the reaction on the low-index Rh(111) and stepped Rh(211) surfaces. We find that the Rh(111) facet is selective towards methane, while the Rh(211) facet exhibits a similar selectivity towards methane and acetaldehyde. This is consistent with the experimental selectivity observed for larger, predominantly (111)-exposing Rh nanoparticles and resolves the discrepancy to earlier first-principles MFA microkinetic work that found the Rh(111) facet to be selective towards acetaldehyde. While the latter work tried to approximately account for lateral interactions through coverage-dependent rate expressions, our analysis demonstrates that this fails to sufficiently capture concomitant correlations among the adsorbed reaction intermediates that crucially determine the overall selectivity.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Wafer-scale epitaxial modulation of quantum dot density},

author = {N Bart and C Dangel and P Zajac and N Spitzer and J Ritzmann and M Schmidt and H G Babin and R Schott and S R Valentin and S Scholz and Y Wang and R Uppu and D Najer and M C L\"{o}bl and N Tomm and A Javadi and N O Antoniadis and L Midolo and K M\"{u}ller and R J Warburton and P Lodahl and A D Wieck and J J Finley and A Ludwig},

url = {https://doi.org/10.1038/s41467-022-29116-8},

doi = {10.1038/s41467-022-29116-8},

issn = {2041-1723},

year  = {2022},

date = {2022-03-28},

journal = {Nature Communications},

volume = {13},

number = {1},

pages = {1633},

abstract = {Precise control of the properties of semiconductor quantum dots (QDs) is vital for creating novel devices for quantum photonics and advanced opto-electronics. Suitable low QD-densities for single QD devices and experiments are challenging to control during epitaxy and are typically found only in limited regions of the wafer. Here, we demonstrate how conventional molecular beam epitaxy (MBE) can be used to modulate the density of optically active QDs in one- and two- dimensional patterns, while still retaining excellent quality. We find that material thickness gradients during layer-by-layer growth result in surface roughness modulations across the whole wafer. Growth on such templates strongly influences the QD nucleation probability. We obtain density modulations between 1 and 10 QDs/µm2 and periods ranging from several millimeters down to at least a few hundred microns. This method is universal and expected to be applicable to a wide variety of different semiconductor material systems. We apply the method to enable growth of ultra-low noise QDs across an entire 3-inch semiconductor wafer.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Band gap and electronic structure of defects in the ternary nitride BP3N6: experiment and theory},

author = {T De Boer and M F A Fattah and M R Amin and S J Ambach and S Vogel and W Schnick and A Moewes},

url = {https://doi.org/10.1039/D1TC06009K},

doi = {10.1039/D1TC06009K},

issn = {2050-7526},

year  = {2022},

date = {2022-03-28},

urldate = {2022-03-28},

journal = {Journal of Materials Chemistry C},

volume = {10},

pages = {6429-6434},

abstract = {Recent advances in methods to access nitride systems by a high-pressure high-temperature approach have made possible the one-step synthesis of mixed ternary non-metal nitrides. As a prerequisite to use in a practical device, it is important to understand important bulk electronic properties, such as the band gap, as well as characterizing the presence and effect of defects that are present. In this work, the novel ternary nitride BP3N6 is studied using techniques sensitive to the partial electronic density of states, specifically X-ray absorption spectroscopy and X-ray emission spectroscopy. Complementary full-potential all-electron density functional theory (DFT) calculations allow important bulk electronic parameters, such as the band gap, to be elucidated. The band gap of BP3N6 has been determined to be 3.9 ± 0.2 eV and 4.1 ± 0.4 eV at the B K- and N K-edges, respectively. This is close to a theoretical value of 4.3 eV predicted by the PBEsol exchange\textendashcorrelation functional and considerably less than a value of 5.8 eV predicted by the modified Becke\textendashJohnson exchange\textendashcorrelation functional. X-Ray excited optical luminescence (XEOL) measurements are performed to interrogate the presence of point defects in this system. Together with DFT calculations, these measurements reveal the presence of nitrogen vacancies which lead to multiple mid-gap trap states.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Self-doping behavior and cation disorder in MgSnN2},

author = {D Han and S S Rudel and W Schnick and H Ebert},

url = {https://link.aps.org/doi/10.1103/PhysRevB.105.125202},

doi = {10.1103/PhysRevB.105.125202},

year  = {2022},

date = {2022-03-28},

journal = {Physical Review B},

volume = {105},

number = {12},

pages = {125202},

abstract = {Investigations on II−Sn−N2(II=Mg, Ca) have been started very recently compared to the intense research of Zn−IV−N2 (IV=Si, Ge, Sn). In this work, we study the phase stability of MgSnN2 and ZnSnN2 in wurtzite and rocksalt phases by first principles calculations. The calculated phase diagram agrees with the experimental observation; i.e., MgSnN2 can form in the wurtzite and rocksalt phases while ZnSnN2 only crystallizes in the wurtzite phase. Due to the higher ionicity of Mg-N bonds compared to Sn-N bonds and Zn-N bonds, wurtzite-type 

MgSnN2 appears under Mg-rich conditions. The defect properties and doping behavior of MgSnN2 in the wurtzite phase are further investigated. We find that MgSnN2 exhibits self-doped n-type conductivity, and donor-type antisite defect SnMg is the primary source of free electrons. The high possibility of forming the stoichiometry-preserving MgSn+SnMg defect complex leads to our study of cation disorder in MgSnN2 by using the cluster expansion method with first principles calculations. It is found that cation disorder in MgSnN2 induces a band-gap reduction because of a violation of the octet rule. The local disorder, namely, forming (4,0) or (0,4) tetrahedra, leads to an appreciable band-gap reduction and hinders the enhancement of the optical absorption.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Scalable, Highly Crystalline, 2D Semiconductor Atomic Layer Deposition Process for High Performance Electronic Applications},

author = {N Aspiotis and K Morgan and B M\"{a}rz and K M\"{u}ller-Caspary and M Ebert and C-C Huang and D W Hewak and S Majumdar and I Zeimpekis},

url = {https://arxiv.org/abs/2203.10309},

doi = {https://doi.org/10.48550/arXiv.2203.10309},

year  = {2022},

date = {2022-03-19},

journal = {arXiv preprint arXiv:2203.10309},

abstract = {This work demonstrates a large area process for atomically thin 2D semiconductors to unlock the technological upscale required for their commercial uptake. The new atomic layer deposition (ALD) and conversion technique yields large area performance uniformity and tunability. Like graphene, 2D Transition Metal Dichalcogenides (TMDCs) are prone to upscaling challenges limiting their commercial uptake. They are challenging to grow uniformly on large substrates and to transfer on alternative substrates while they often lack in large area electrical performance uniformity. The scalable ALD process of this work enables uniform growth of 2D TMDCs on large area with independent control of layer thickness, stoichiometry and crystallinity while allowing chemical free transfers to application substrates. Field effect transistors (FETs) fabricated on flexible substrates using the process present a field effect mobility of up to 55 cm^2/Vs, subthreshold slope down to 80 mV/dec and on/off ratios of 10^7. Additionally, non-volatile memory transistors using ferroelectric FETs (FeFETs) operating at +-5 V with on/off ratio of 107 and a memory window of 3.25 V are demonstrated. These FeFETs demonstrate state-of-the-art performance with multiple state switching, suitable for one-transistor non-volatile memory and for synaptic transistors revealing the applicability of the process to flexible neuromorphic applications.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Hydrophobic Graphene Quantum Dots for Defect Passivation and Enhanced Moisture Stability of CH3NH3PbI3 Perovskite Solar Cells},

author = {E Khorshidi and B Rezaei and D Bl\"{a}tte and A Buyruk and M A Reus and J Hanisch and B B\"{o}ller and P M\"{u}ller-Buschbaum and T Ameri},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202200023},

doi = {https://doi.org/10.1002/solr.202200023},

issn = {2367-198X},

year  = {2022},

date = {2022-03-19},

journal = {Solar RRL},

volume = {n/a},

number = {n/a},

pages = {2200023},

abstract = {Passivating the defects and grain boundaries (GBs) of perovskite films at the interface by interface engineering is a promising route to achieve efficient and stable perovskite solar cells (PSCs). Herein, a new type of graphene, that is, hydrophobic graphene quantum dots (HGQDs) containing amide linkages, which consist of carbonyl and dodecyl amine groups, is successfully used as a bifunctional interface modifier to engineer the interface of the perovskite/hole transport layer. A comprehensive characterization including X-ray photoelectron spectroscopy, Fourier-transform photocurrent spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and space-charge-limited current measurements is performed to identify the underlying passivation mechanisms. It can be demonstrated that the HGQDs, due to the bifunctional groups containing N and O atoms, effectively passivate the uncoordinated Pb2+ ions at the perovskite film surface and GBs and consequently induce a lower trap state density. Moreover, HGQDs enhance the quality of the perovskite film which reduces the charge recombination at the interface. Therefore, the power conversion efficiency of PSCs treated with HGQDs is significantly increased from 16.00% to 18.30%, mainly based on the improved open-circuit voltage and fill factor. Importantly, the HGQDs featuring hydrophobicity due to alkyl chains significantly enhance moisture stability.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electron\textendashHole Binding Governs Carrier Transport in Halide Perovskite Nanocrystal Thin Films},

author = {M F Lichtenegger and J Drewniok and A Bornschlegl and C Lampe and A Singldinger and N A Henke and A S Urban},

url = {https://doi.org/10.1021/acsnano.2c00369},

doi = {10.1021/acsnano.2c00369},

issn = {1936-0851},

year  = {2022},

date = {2022-03-18},

journal = {ACS Nano},

abstract = {Two-dimensional halide perovskite nanoplatelets (NPLs) have exceptional light-emitting properties, including wide spectral tunability, ultrafast radiative decays, high quantum yields (QY), and oriented emission. Due to the high binding energies of electron\textendashhole pairs, excitons are generally considered the dominant species responsible for carrier transfer in NPL films. To realize efficient devices, it is imperative to understand how exciton transport progresses therein. We employ spatially and temporally resolved optical microscopy to map exciton diffusion in perovskite nanocrystal (NC) thin films between 15 °C and 55 °C. At room temperature (RT), we find the diffusion length to be inversely correlated to the thickness of the nanocrystals (NCs). With increasing temperatures, exciton diffusion declines for all NC films, but at different rates. This leads to specific temperature turnover points, at which thinner NPLs exhibit higher diffusion lengths. We attribute this anomalous diffusion behavior to the coexistence of excitons and free electron hole-pairs inside the individual NCs within our temperature range. The organic ligand shell surrounding the NCs prevents charge transfer. Accordingly, any time an electron\textendashhole pair spends in the unbound state reduces the FRET-mediated inter-NC transfer rates and, consequently, the overall diffusion. These results clarify how exciton diffusion progresses in strongly confined halide perovskite NC films, emphasizing critical considerations for optoelectronic devices.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Anharmonic Lattice Dynamics in Sodium Ion Conductors},

author = {T M Brenner and M Grumet and P Till and M Asher and W G Zeier and D A Egger and O Yaffe},

url = {https://arxiv.org/abs/2203.07955},

doi = {https://doi.org/10.48550/arXiv.2203.07955},

year  = {2022},

date = {2022-03-15},

journal = {arXiv preprint arXiv:2203.07955},

abstract = {We employ THz-range temperature-dependent Raman spectroscopy and first-principles lattice-dynamical calculations to show that the undoped sodium ion conductors Na3PS4 and isostructural Na3PSe4 both exhibit anharmonic lattice dynamics. The anharmonic effects in the compounds involve coupled host lattice -- Na+ ion dynamics that drive the tetragonal-to-cubic phase transition in both cases, but with a qualitative difference in the anharmonic character of the transition. Na3PSe4 shows almost purely displacive character with the soft modes disappearing in the cubic phase as the change of symmetry shifts these modes to the Raman-inactive Brillouin zone boundary. Na3PS4 instead shows order-disorder character in the cubic phase, with the soft modes persisting through the phase transition and remaining active in Raman in the cubic phase, violating Raman selection rules for that phase. Our findings highlight the important role of coupled host lattice -- mobile ion dynamics in vibrational instabilities that are coincident with the exceptional conductivity in these Na+ ion conductors.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Dual In-situ Laser Techniques Underpin the Role of Cations in Impacting Electrocatalysts},

author = {S Hou and L Xu and X Ding and R M Kluge and T K Sarpey and R W Haid and B Garlyyev and S Mukherjee and J Warnan and M Koch and S Zhang and W Li and A S Bandarenka and R A Fischer},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202201610},

doi = {https://doi.org/10.1002/anie.202201610},

issn = {1433-7851},

year  = {2022},

date = {2022-03-10},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

abstract = {Understanding the electrode/electrolyte interface is crucial for optimizing electrocatalytic performances. Here, we demonstrate that the nature of alkali metal cations can profoundly impact the oxygen evolution activity of surface-mounted metal-organic framework (SURMOF) derived electrocatalysts, which are based on NiFe(OOH). In-situ Raman spectroscopy results show that Raman shifts of the Ni-O bending vibration are inversely proportional to the mass activities from Cs+ to Li+. Particularly, a laser-induced current transient technique was introduced to study the cation-dependent electric double layer properties and their effects on the activity. The catalytic trend appeared to be closely related to the potential of maximum entropy of the system, suggesting a strong cation impact on the interfacial water layer structure. Our results highlight how the electrolyte composition can be used to maximize the performance of SURMOF derivatives toward electrochemical water splitting.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Multifaceted Role of the Noninnocent Mabiq Ligand in Promoting Selective Reduction of CO2 to CO},

author = {K Rickmeyer and L Niederegger and M Keilwerth and C R Hess},

url = {https://doi.org/10.1021/acscatal.1c04636},

doi = {10.1021/acscatal.1c04636},

year  = {2022},

date = {2022-02-21},

journal = {ACS Catalysis},

pages = {3046-3057},

abstract = {We have investigated the ability of Co\textendash and Fe\textendashMabiq complexes (Mabiq = 2\textendash4:6\textendash8-bis(3,3,4,4-tetramethyldihydropyrrolo)-10-15-(2,2′-biquinazolino)-[15]-1,3,5,8,10,14-hexaene1,3,7,9,11,14-N6) to act as electrocatalysts for CO2 reduction. We observed marked differences in activity when switching the metal center, as the Fe complex outperforms its Co-containing analogue, both in terms of overpotential (η) and faradaic efficiency (FE). [Fe(Mabiq)2(MeCN)2]PF6 ([2]+) selectively reduces CO2 to CO with an overpotential requirement of 500 mV. We have synthesized and fully characterized the two-electron reduced Na(OEt2)[Fe(Mabiq)] ([2]\textendash), which consists of an intermediate spin FeII center coupled to a ligand biradical and exhibits a unique S = 1 spin state. Both electrochemical and reactivity studies with [2]\textendash point toward a protonated precatalytic intermediate (IPhOH). The molecular structure of IPhOH indicates the diketiminate carbon as the site of protonation and the ability of the Mabiq ligand to engage in hydrogen bonding interactions. The noninnocent Mabiq ligand, therefore, acts not only as an electron reservoir but also as a proton storage site. Our ligand system uniquely combines two beneficial features, a redox-active unit and a proton donor site, that in combination with the metal ion reduces overpotentials and facilitates selective CO2 conversion.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Discovery of Two Polymorphs of TiP4N8 Synthesized from Binary Nitrides},

author = {L Eisenburger and V Weippert and C Paulmann and D Johrendt and O Oeckler and W Schnick},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202202014},

doi = {https://doi.org/10.1002/anie.202202014},

issn = {1433-7851},

year  = {2022},

date = {2022-02-18},

journal = {Angewandte Chemie International Edition},

volume = {n/a},

number = {n/a},

pages = {e202202014},

abstract = {Abstract TiP4N8 was obtained from the binary nitrides TiN and P3N5 upon addition of NH4F as a mineralizer at 8 GPa and 1400 °C. An intricate interplay of disorder and polymorphism was elucidated by in situ temperature-dependent single-crystal X-ray diffraction, STEM-HAADF, and the investigation of annealed samples. This revealed two polymorphs, which consist of dense networks of PN4 tetrahedra (degree of condensation κ=0.5) and either augmented triangular TiN7 prisms or triangular TiN6 prisms for α- and β-TiP4N8, respectively. The structures of TiP4N8 exhibit body-centered tetragonal (bct) framework topology. DFT calculations confirm the measured band gaps of α- and β-TiP4N8 (1.6\textendash1.8 eV) and predict the thermochemistry of the polymorphs in agreement with the experiments.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Low-Temperature and Water-Based Biotemplating of Nanostructured Foam-Like Titania Films Using \ss-Lactoglobulin},

author = {J E Heger and W Chen and S Yin and N Li and V K\"{o}rstgens and C J Brett and W Ohm and S V Roth and P M\"{u}ller-Buschbaum},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202113080},

doi = {https://doi.org/10.1002/adfm.202113080},

issn = {1616-301X},

year  = {2022},

date = {2022-02-17},

journal = {Advanced Functional Materials},

volume = {n/a},

number = {n/a},

pages = {2113080},

abstract = {Abstract Given the broad use of nanostructured crystalline titania films, an environmentally friendly and more sustainable synthesis route is highly desirable. Here, a water-based, low-temperature route is presented to synthesize nanostructured foam-like crystalline titania films. A pearl necklace-like nanostructure is introduced as tailored titania morphology via biotemplating with the use of the major bovine whey protein \ss-lactoglobulin (\ss-lg). It is shown that titania crystallization in a brookite-anatase mixed phase is promoted via spray deposition at a comparatively low temperature of 120 °C. The obtained crystallites have an average grain size of (4.2 ± 0.3) nm. In situ grazing incidence small-angle and wide-angle X-ray scattering (GISAXS/GIWAXS) are simultaneously performed to understand the kinetics of film formation and the templating role of \ss-lg during spray coating. In the \ss-lg:titania biohybrid composites, the crystal growth in semicrystalline titania clusters is sterically directed by the condensing \ss-lg biomatrix. Due to using spray coating, the green chemistry approach to titania-based functional films can be scaled up on a large scale, which can potentially be used in photocatalytic processes or systems related to energy application.},

keywords = {Foundry Inorganic, Molecularly-Functionalized},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Ultrafast sub-100 fs all-optical modulation and efficient third-harmonic generation in Weyl semimetal niobium phosphide thin films},

author = {B Tilmann and A K Pandeya and G Grinblat and L D S Menezes and Y Li and C Shekhar and C Felser and S S P Parkin and A Bedoya-Pinto and S A Maier},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202106733},

doi = {https://doi.org/10.1002/adma.202106733},

issn = {0935-9648},

year  = {2022},

date = {2022-02-16},

journal = {Advanced Materials},

volume = {n/a},

number = {n/a},

pages = {2106733},

abstract = {Abstract Since their experimental discovery in 2015, Weyl semimetals generated a large amount of attention due their intriguing physical properties that arise from their linear electron dispersion relation and topological surface states. In particular in the field of nonlinear (NL) optics and light harvesting, Weyl semimetals have shown outstanding performances and achieved record NL conversion coefficients. In this context, we perform first steps towards Weyl semimetal nanophotonics by thoroughly characterizing the linear and NL optical behavior of epitaxially grown niobium phosphide (NbP) thin films, covering the visible to near-infrared regime of the electromagnetic spectrum. Despite the measured high linear absorption, third-harmonic generation studies demonstrate high conversion efficiencies up to 10-4%, that can be attributed to the topological electron states at the surface of the material. Furthermore, nondegenerate pump-probe measurements with sub-10 fs pulses reveal a maximum modulation depth of about 1%, completely decaying within 100 fs and therefore suggesting the possibility of developing devices based on NbP with all-optical switching bandwidths of up to 10 THz. Altogether, our work reveals promising NL optical properties of Weyl semimetal thin films that are outperforming bulk crystals of the same material, laying the grounds for nanoscale applications, enabled by top-down nanostructuring, such as light-harvesting, on-chip frequency conversion and all-optical processing. This article is protected by copyright. All rights reserved},

keywords = {Foundry Inorganic},

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 = {Foundry Inorganic, Molecularly-Functionalized},

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 = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Correlated spectral fluctuations quantified by line shape analysis of fifth-order two-dimensional electronic spectra},

author = {C Heshmatpour and J Hauer and F \v{S}anda},

url = {https://aip.scitation.org/doi/abs/10.1063/5.0081053},

doi = {10.1063/5.0081053},

year  = {2022},

date = {2022-02-01},

journal = {The Journal of Chemical Physics},

volume = {156},

number = {8},

pages = {084114},

abstract = {Correlated spectral fluctuations were suggested to coordinate excitation transport inside natural light harvesting complexes. We demonstrate the capacities of 2D line shapes from fifth-order coherent electronic signals (R5-2D) to report on such fluctuations in molecular aggregates and present a stochastic approach to fluctuations in correlated site and bi-exciton binding energies in the optical dynamics of Frenkel excitons. The model is applied to R5-2D line shapes of a homodimer, and we show that the peak tilt dynamics are a measure for site energy disorder, inter-site correlation, and the strength of bi-exciton binding energy fluctuations.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Single-photon emitters in layered van der Waals materials},

author = {S Michaelis De Vasconcellos and D Wigger and U Wurstbauer and A W Holleitner and R Bratschitsch and T Kuhn},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/pssb.202100566},

doi = {https://doi.org/10.1002/pssb.202100566},

issn = {0370-1972},

year  = {2022},

date = {2022-01-28},

journal = {physica status solidi (b)},

volume = {n/a},

number = {n/a},

abstract = {Single-photon emitters have recently been discovered in various atomically thin materials. Their properties, controllability, and the possibility of their monolithic integration in electronic and photonic device structures makes them attractive candidates for a wide range of applications in quantum information and communication, and also in other fields of physics and technology. In this review article an overview of single-photon emitters in layered van der Waals materials and their physical properties is given, theoretical concepts for the modeling of their level structure and their coupling to phonons are presented, and techniques for the creation and localization of these emitters in the host material are described. Perspectives for their application in various fields, such as their coupling to photonic resonators and waveguides, their control by external electric fields or strain, and their integration in optomechanical devices are discussed. Finally, functionalities relying on properties beyond single-photon emission are briefly addressed. This article is protected by copyright. All rights reserved.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Robust excitons across the phase transition of two-dimensional hybrid perovskites},

author = {J D Ziegler and K-Q Lin and B Meisinger and X Zhu and M Kober-Czerny and P K Nayak and C Vona and T Taniguchi and K Watanabe and C Draxl},

url = {https://arxiv.org/abs/2201.11589},

doi = {arXiv:2201.11589v1},

year  = {2022},

date = {2022-01-27},

journal = {arXiv preprint arXiv:2201.11589},

abstract = {Two-dimensional halide perovskites are among intensely studied materials platforms profiting from solution based growth and chemical flexibility. They feature exceptionally strong interactions among electronic, optical as well as vibrational excitations and hold a great potential for future optoelectronic applications. A key feature for these materials is the occurrence of structural phase transitions that can impact their functional properties, including the electronic band gap and optical response dominated by excitons. However, to what extent the phase-transitions in two-dimensional perovskites alter the fundamental exciton properties remains barely explored so far. Here, we study the influence of the phase transition on both exciton binding energy and exciton diffusion, demonstrating their robust nature across the phase transition. These findings are unexpected in view of the associated substantial changes of the free carrier masses, strongly contrast broadly considered effective mass and drift-diffusion transport mechanisms, highlighting the unusual nature of excitons in two-dimensional perovskites.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electronically Tunable Transparent Conductive Thin Films for Scalable Integration of 2D Materials with Passive 2D\textendash3D Interfaces},

author = {T Gr\"{u}nleitner and A Henning and M Bissolo and A Kleibert and C F Vaz and A V Stier and J J Finley and I D Sharp},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202111343},

doi = {https://doi.org/10.1002/adfm.202111343},

issn = {1616-301X},

year  = {2022},

date = {2022-01-22},

journal = {Advanced Functional Materials},

volume = {n/a},

number = {n/a},

pages = {2111343},

abstract = {Abstract A novel transparent conductive support structure for scalable integration of 2D materials is demonstrated, providing an electronically passive 2D\textendash3D interface while also enabling facile interfacial charge transport. This structure, which comprises an evaporated nanocrystalline carbon (nc-C) film beneath nanometer-thin atomic layer deposited AlOx, is thermally stable and allows direct chemical vapor deposition of 2D materials onto the surface. The combination of spatial uniformity, enhanced charge screening, and low interface defect concentrations yields a tenfold enhancement of MoS2 photoluminescence intensity compared to flakes on conventional Si/SiO2, while also retaining the strong optical contrast for monolayer flakes. Tunneling across the ultrathin AlOx enables facile interfacial charge injection, which is utilized for high-resolution scanning electron microscopy and photoemission electron microscopy with no detectable charging. Thus, this combination of scalable fabrication and electronic conductivity across a weakly interacting 2D\textendash3D interface opens up new opportunities for device integration and characterization of 2D materials.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Light-driven carbon nitride microswimmers with propulsion in biological and ionic media and responsive on-demand drug delivery},

author = {V Sridhar and F Podjaski and Y Alapan and J Kr\"{o}ger and L Grunenberg and V Kishore and B V Lotsch and M Sitti},

url = {https://www.science.org/doi/abs/10.1126/scirobotics.abm1421},

doi = {doi:10.1126/scirobotics.abm1421},

year  = {2022},

date = {2022-01-19},

journal = {Science Robotics},

volume = {7},

number = {62},

pages = {eabm1421},

abstract = {We propose two-dimensional poly(heptazine imide) (PHI) carbon nitride microparticles as light-driven microswimmers in various ionic and biological media. Their high-speed (15 to 23 micrometer per second; 9.5 ± 5.4 body lengths per second) swimming in multicomponent ionic solutions with concentrations up to 5 M and without dedicated fuels is demonstrated, overcoming one of the bottlenecks of previous light-driven microswimmers. Such high ion tolerance is attributed to a favorable interplay between the particle’s textural and structural nanoporosity and optoionic properties, facilitating ionic interactions in solutions with high salinity. Biocompatibility of these microswimmers is validated by cell viability tests with three different cell lines and primary cells. The nanopores of the swimmers are loaded with a model cancer drug, doxorubicin (DOX), resulting in a high (185%) loading efficiency without passive release. Controlled drug release is reported under different pH conditions and can be triggered on-demand by illumination. Light-triggered, boosted release of DOX and its active degradation products are demonstrated under oxygen-poor conditions using the intrinsic, environmentally sensitive and light-induced charge storage properties of PHI, which could enable future theranostic applications in oxygen-deprived tumor regions. These organic PHI microswimmers simultaneously address the current light-driven microswimmer challenges of high ion tolerance, fuel-free high-speed propulsion in biological media, biocompatibility, and controlled on-demand cargo release toward their biomedical, environmental, and other potential applications.},

keywords = {Foundry Inorganic, Molecularly-Functionalized},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Designing multifunctional CoOx layers for efficient and stable electrochemical energy conversion},

author = {M Kuhl and A Henning and L Haller and L Wagner and C-M Jiang and V Streibel and I D Sharp and J Eichhorn},

doi = {10.26434/chemrxiv-2022-23ck4},

year  = {2022},

date = {2022-01-13},

urldate = {2022-01-13},

journal = {Cambridge: Cambridge Open Engage},

abstract = {Disordered and porous metal oxides are promising as earth-abundant and cost-effective alternatives to noble-metal electrocatalysts. Herein, we leverage non-saturated oxidation in plasma-enhanced atomic layer deposition to tune structural, mechanical, and optical properties of biphasic CoOx thin films, thereby tailoring their catalytic activities and chemical stabilities. To optimize the resulting film properties, we systematically vary the oxygen plasma power and exposure time in the deposition process. We find that short exposure times and low plasma powers incompletely oxidize the cobaltocene precursor to Co(OH)2 and result in the incorporation of carbon impurities. These Co(OH)2 films are highly porous and catalytically active, but their electrochemical stability is impacted by poor adhesion to the substrate. In contrast, long exposure times and high plasma powers completely oxidize the precursor to form Co3O4, reduce the carbon impurity incorporation, and improve the film crystallinity. While the resulting Co3O4 films are highly stable under electrochemical conditions, they are characterized by low oxygen evolution reaction activities. To overcome these competing properties, we applied the established relation between deposition parameters and functional film properties to design bilayer films exhibiting simultaneously improved electrochemical performance and chemical stability. The resulting biphasic films combine a highly active Co(OH)2 surface with a stable Co3O4 interface layer. In addition, these coatings exhibit minimal light absorption, thus rendering them well suited as protective catalytic layers on semiconductor light absorbers for application in photoelectrochemical devices.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Doubly Stabilized Perovskite Nanocrystal Luminescence Downconverters},

author = {Q Xue and C Lampe and T Naujoks and K Frank and M Gramlich and M Schoger and W Vanderlinden and P Reisbeck and B Nickel and W Br\"{u}tting},

url = {https://arxiv.org/abs/2201.05472v1},

doi = {arXiv:2201.05472v1},

year  = {2022},

date = {2022-01-13},

journal = {arXiv preprint arXiv:2201.05472},

abstract = {Halide perovskite nanocrystals (NCs) have emerged as a promising material for applications ranging from light-emitting diodes (LEDs) to solar cells and photodetectors. Still, several issues impede the realization of the nanocrystals' full potential, most notably their susceptibility to degradation from environmental stress. This work demonstrates highly stable perovskite nanocrystals (NCs) with quantum yields as high as 95 % by exploiting a ligand-assisted copolymer nanoreactor-based synthesis. The organic ligands thereby serve a dual function by enhancing the uptake of precursors and passivating the NCs. The polymer micelles and ligands thus form a double protection system, shielding the encapsulated NCs from water-, heat- and UV-light-induced degradation. We demonstrate the optoelectronic integrability by incorporating the perovskite NCs as spectrally pure downconverters on top of a deep-blue-emitting organic LED. These results establish a way of stabilizing perovskite NCs for optoelectronics while retaining their excellent optical properties.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {A novel electrically conductive perylene diimide-based MOF-74 series featuring luminescence and redox activity},

author = {P I Scheurle and A Biewald and A M\"{a}hringer and A Hartschuh and D D Medina and T Bein},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/sstr.202100195},

doi = {https://doi.org/10.1002/sstr.202100195},

issn = {2688-4062},

year  = {2022},

date = {2022-01-11},

journal = {Small Structures},

volume = {n/a},

number = {n/a},

abstract = {Metal-organic frameworks (MOFs) featuring significant electrical conductivity constitute a growing class of materials, with intriguing possible applications as porous semiconductors or supercapacitors. If such features are combined with photoluminescence, additional functionalities such as selective chemical sensing become accessible. Here, we incorporate perylene diimide (PDI) based linear building blocks into the MOF-74 topology with the three metal ions Zn2+, Mg2+ and Ni2+, resulting in a new series of MOFs, namely PDI-MOF-74(M). PDI derivatives are dye molecules exhibiting remarkable optical properties, high electron mobilities, as well as interesting redox behavior. However, PDI-based 3D MOFs are very rare and to date were only reported once. The frameworks of the PDI-MOF-74(M) series exhibit high crystallinity, electrical conductivity and show well-defined redox activity. In addition, the frameworks of the series feature photoluminescence in the orange and red spectral regions. With this work we expand the series of electroactive MOF-74 structures as well as the group of 3D PDI-based MOFs, hence opening up the development of novel MOFs with promising optoelectronic properties comprising PDI building blocks. This article is protected by copyright. All rights reserved.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {2D/3D Hybrid Cs2AgBiBr6 Double Perovskite Solar Cells: Improved Energy Level Alignment for Higher Contact-Selectivity and Large Open Circuit Voltage},

author = {M T Sirtl and R Hooijer and M Armer and F G Ebadi and M Mohammadi and C Maheu and A Weis and B T Van Gorkom and S H\"{a}ringer and R J Janssen and T Mayer and V Dyakonov and W Tress and T Bein},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202103215},

doi = {https://doi.org/10.1002/aenm.202103215},

issn = {1614-6832},

year  = {2022},

date = {2022-01-09},

journal = {Advanced Energy Materials},

volume = {n/a},

number = {n/a},

pages = {2103215},

abstract = {Abstract Since their introduction in 2017, the efficiency of lead-free halide perovskite solar cells based on Cs2AgBiBr6 has not exceeded 3%. The limiting bottlenecks are attributed to a low electron diffusion length, self-trapping events and poor selectivity of the contacts, leading to large non-radiative VOC losses. Here, 2D/3D hybrid double perovskites are introduced for the first time, using phenethyl ammonium as the constituting cation. The resulting solar cells show an increased efficiency of up to 2.5% for the champion cells and 2.03% on average, marking an improvement by 10% compared to the 3D reference on mesoporous TiO2. The effect is mainly due to a VOC improvement by up to 70 mV on average, yielding a maximum VOC of 1.18 V using different concentrations of phenethylammonium bromide. While these are among the highest reported VOC values for Cs2AgBiBr6 solar cells, the effect is attributed to a change in recombination behavior within the full device and a better selectivity at the interface toward the hole transporting material (HTM). This explanation is supported by voltage-dependent external quantum efficiency, as well as photoelectron spectroscopy, revealing a better energy level alignment and thus a better hole-extraction and improved electron blocking at the HTM interface.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {SnBrP-A SnIP-type representative in the Sn−Br−P system},

author = {F Reiter and M Pielmeier and A Vogel and C Jandl and M Plodinec and C Rohner and T Lunkenbein and K Nisi and A W Holleitner and T Nilges},

url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/zaac.202100347},

doi = {https://doi.org/10.1002/zaac.202100347},

issn = {0044-2313},

year  = {2022},

date = {2022-01-07},

urldate = {2022-01-07},

journal = {Zeitschrift f\"{u}r anorganische und allgemeine Chemie},

volume = {n/a},

number = {n/a},

pages = {e202100347},

abstract = {Abstract One-dimensional semiconductors are interesting materials due to their unique structural features and anisotropy, which grant them intriguing optical, dielectric and mechanical properties. In this work, we report on SnBrP, a lighter homologue of the first inorganic double helix compound SnIP. This class of compounds is characterized by intriguing mechanical and electronic properties, featuring a high flexibility without modulation of physical properties. Semiconducting SnBrP can be synthesized from red phosphorus, tin and tin(II)bromide at elevated temperatures and crystallizes as red-orange, cleavable needles. Raman measurements pointed towards a double helical building unit in SnBrP, showing similarities to the SnIP structure. After taking PL measurements, HR-TEM, and quantum chemical calculations into account, we were able to propose a sense full structure model for SnBrP.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Electrolyte Effects on the Stabilization of Prussian Blue Analogue Electrodes in Aqueous Sodium-Ion Batteries},

author = {X Lamprecht and F Speck and P Marzak and S Cherevko and A S Bandarenka},

url = {https://doi.org/10.1021/acsami.1c21219},

doi = {10.1021/acsami.1c21219},

issn = {1944-8244},

year  = {2022},

date = {2022-01-06},

urldate = {2022-01-06},

journal = {ACS Applied Materials \& Interfaces},

volume = {14},

pages = {3515-3525},

abstract = {Aqueous sodium-ion batteries based on Prussian Blue Analogues (PBA) are considered as promising and scalable candidates for stationary energy storage systems, where longevity and cycling stability are assigned utmost importance to maintain economic viability. Although degradation due to active material dissolution is a common issue of battery electrodes, it is hardly observable directly due to a lack of in operando techniques, making it challenging to optimize the performance of electrodes. By operating Na2Ni[Fe(CN)6] and Na2Co[Fe(CN)6] model electrodes in a flow-cell setup connected to an inductively coupled plasma mass spectrometer, in this work, the dynamics of constituent transition-metal dissolution during the charge\textendashdischarge cycles was monitored in real time. At neutral pHs, the extraction of nickel and cobalt was found to drive the degradation process during charge\textendashdischarge cycles. It was also found that the nature of anions present in the electrolytes has a significant impact on the degradation rate, determining the order ClO4\textendash > NO3\textendash > Cl\textendash > SO42\textendash with decreasing stability from the perchlorate to sulfate electrolytes. It is proposed that the dissolution process is initiated by detrimental specific adsorption of anions during the electrode oxidation, therefore scaling with their respective chemisorption affinity. This study involves an entire comparison of the effectiveness of common stabilization strategies for PBAs under very fast (dis)charging conditions at 300C, emphasizing the superiority of highly concentrated NaClO4 with almost no capacity loss after 10 000 cycles for Na2Ni[Fe(CN)6].},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {The Influence of CsBr on Crystal Orientation and Optoelectronic Properties of MAPbI3-Based Solar Cells},

author = {Y Zou and S Yuan and A Buyruk and J Eichhorn and S Yin and M A Reus and T Xiao and S Pratap and S Liang and C L Weindl and W Chen and C Mu and I D Sharp and T Ameri and M Schwartzkopf and S V Roth and P M\"{u}ller-Buschbaum},

url = {https://doi.org/10.1021/acsami.1c22184},

doi = {10.1021/acsami.1c22184},

issn = {1944-8244},

year  = {2022},

date = {2022-01-06},

urldate = {2022-01-06},

journal = {ACS Applied Materials \& Interfaces},

volume = {14},

pages = {2958},

abstract = {Crystal orientations are closely related to the behavior of photogenerated charge carriers and are vital for controlling the optoelectronic properties of perovskite solar cells. Herein, we propose a facile approach to reveal the effect of lattice plane orientation distribution on the charge carrier kinetics via constructing CsBr-doped mixed cation perovskite phases. With grazing-incidence wide-angle X-ray scattering measurements, we investigate the crystallographic properties of mixed perovskite films at the microscopic scale and reveal the effect of the extrinsic CsBr doping on the stacking behavior of the lattice planes. Combined with transient photocurrent, transient photovoltage, and space-charge-limited current measurements, the transport dynamics and recombination of the photogenerated charge carriers are characterized. It is demonstrated that CsBr compositional engineering can significantly affect the perovskite crystal structure in terms of the orientation distribution of crystal planes and passivation of trap-state densities, as well as simultaneously facilitate the photogenerated charge carrier transport across the absorber and its interfaces. This strategy provides unique insight into the underlying relationship between the stacking pattern of crystal planes, photogenerated charge carrier transport, and optoelectronic properties of solar cells.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Tuning the Optical Properties of a MoSe2 Monolayer Using Nanoscale Plasmonic Antennas},

author = {M M Petri\'{c} and M Kremser and M Barbone and A Nolinder and A Lyamkina and A V Stier and M Kaniber and K M\"{u}ller and J J Finley},

url = {https://doi.org/10.1021/acs.nanolett.1c02676},

doi = {10.1021/acs.nanolett.1c02676},

issn = {1530-6984},

year  = {2022},

date = {2022-01-03},

journal = {Nano Letters},

volume = {22},

number = {2},

pages = {561-569},

abstract = {Nanoplasmonic systems combined with optically active two-dimensional materials provide intriguing opportunities to explore and control light\textendashmatter interactions at extreme subwavelength length scales approaching the exciton Bohr radius. Here, we present room- and cryogenic-temperature investigations of a MoSe2 monolayer on individual gold dipole nanoantennas. By controlling nanoantenna size, the dipolar resonance is tuned relative to the exciton achieving a total tuning of ∼130 meV. Differential reflectance measurements performed on >100 structures reveal an apparent avoided crossing between exciton and dipolar mode and an exciton\textendashplasmon coupling constant of g = 55 meV, representing g/(ℏωX) ≥ 3% of the transition energy. This places our hybrid system in the intermediate-coupling regime where spectra exhibit a characteristic Fano-like shape. We demonstrate active control by varying the polarization of the excitation light to programmably suppress coupling to the dipole mode. We further study the emerging optical signatures of the monolayer localized at dipole nanoantennas at 10 K.},

keywords = {Foundry Inorganic, Solid-Solid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {A Systematic Study of the Influence of Electrolyte Ions on the Electrode Activity},

author = {X Ding and D Scieszka and S Watzele and S Xue and B Garlyyev and R W Haid and A S Bandarenka},

url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/celc.202101088},

doi = {https://doi.org/10.1002/celc.202101088},

issn = {2196-0216},

year  = {2022},

date = {2022-01-01},

urldate = {2021-11-22},

journal = {ChemElectroChem},

volume = {9},

number = {1},

pages = {e202101088},

abstract = {Abstract Efficient electrocatalysis is most likely an answer to recent energy related challenges. Countless studies have been trying to find the links between the electrode/electrolyte interface structure, its composition, and the resulting activity in order to improve the performance of numerous devices, such as electrolyzers, fuel cells, and certain types of batteries. However, this scientific field currently meets serious complications associated with the prediction and explanation of an unexpected influence of seemingly inert electrolyte components on the observed activity. Herein, we investigate various electrocatalytic systems using a unique laser-induced current transient technique to answer a long-lasting fundamental question: How can “inert” electrolytes change the activity so drastically? Different metal electrodes in contact with various aqueous solutions and two energy important reactions were used as model systems. We experimentally determine the potential of maximum entropy of the electrodes and find the connections between its position and the electrocatalytic performance.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Prospects of Using the Laser-Induced Temperature Jump Techniques for Characterisation of Electrochemical Systems},

author = {X Ding and T K Sarpey and S Hou and B Garlyyev and W Li and R A Fischer and A S Bandarenka},

url = {https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/celc.202101175},

doi = {https://doi.org/10.1002/celc.202101175},

issn = {2196-0216},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {ChemElectroChem},

volume = {9},

number = {4},

pages = {e20210117},

abstract = {Abstract Understanding the processes, phenomena, and mechanisms occurring at the electrode/electrolyte interface is a prerequisite and significant for optimizing electrochemical systems. To this end, the advent of sub-microsecond laser pulses has paved the way and eased the investigations of the electrochemical interface (e. g., electric double layer), which hitherto is difficult. The laser-induced current transient (LICT) and laser-induced potential transient (LIPT) techniques have proven to be valuable and unique tools for measuring key parameters of the electrified interface, such as the potential of maximum entropy (PME) and the potential of zero charge (PZC). Herein, we present a summary of studies performed in recent years using laser-induced temperature jump techniques. The relation between the PME/PZC and the electrocatalytic properties of various electrochemical interfaces are particularly highlighted. Special attention is given to its applications in investigating different systems and analyzing the influence of the electrolyte components, electrode composition and structure on the PME/PZC and various electrochemical processes. Moreover, possible applications of the LICT/LIPT techniques to investigate the interfacial properties of a myriad of materials, including surface-mounted metal-organic frameworks and metal oxides, are elaborated.},

keywords = {Foundry Inorganic, Solid-Liquid},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Hierarchical porous metal\textendashorganic framework materials for efficient oil\textendashwater separation},

author = {H Saini and E Otyepkov\'{a} and A Schneemann and R Zbo\v{r}il and M Otyepka and R A Fischer and K Jayaramulu},

url = {http://dx.doi.org/10.1039/D1TA10008D},

doi = {10.1039/D1TA10008D},

issn = {2050-7488},

year  = {2022},

date = {2022-01-01},

urldate = {2022-01-01},

journal = {Journal of Materials Chemistry A},

volume = {10},

number = {6},

pages = {2751\textendash2785},

abstract = {Oil contaminated water is a global issue, decreasing the quality of water sources and is posing a threat to the health of humans and many ecosystems. The utilization of industrial level strategies is limited mainly due to their complex and time-consuming processing. Considering this, we choose materials for separating oils from water based on their ease of handling and good performance. However, high surface area porous materials, such as linens, zeolites, cotton, etc., offer low efficiency for oil/water separation. Special wettability is the most promising property of materials and is helpful for oil\textendashwater separation. Metal\textendashorganic frameworks (MOFs), a class of highly tunable porous structures of metal clusters/ions and multidentate organic ligands, offer exciting prospects for various applications. The unique tunability of the structure and properties of these materials can endow them with special wettability for the treatment of oily water. This review focuses on hydrophobic\textendasholeophilic, hydrophilic\textendashunderwater oleophobic and switchable wettability MOFs and their implementation as oil/water separating materials. We classify different MOF-based materials as filtration materials, absorbents or adsorbents based on the methodology they are used in for separating oil/water mixtures and emulsions. We discuss different subclasses of MOF-based filtration, absorbent and adsorbent materials and summarize recent developments in their oil/water separation applications. Finally, we end our discussion by critically analyzing the importance of these MOFs for separating oils from water and highlighting potential future directions for achieving improved performance.},

keywords = {Foundry Inorganic},

pubstate = {published},

tppubtype = {article}

}