Publications

251 entries « ‹ 1 of 6 › »

251.	E Mohammadi, A Tittl, K L Tsakmakidis, T V Raziman, A G Curto Dual Nanoresonators for Ultrasensitive Chiral Detection Journal Article ACS Photonics, 2021. Abstract \| Links \| Tags: Foundry Organic, Solid-Solid @article{, title = {Dual Nanoresonators for Ultrasensitive Chiral Detection}, author = {E Mohammadi and A Tittl and K L Tsakmakidis and T V Raziman and A G Curto}, url = {https://doi.org/10.1021/acsphotonics.1c00311}, doi = {10.1021/acsphotonics.1c00311}, year = {2021}, date = {2021-05-28}, journal = {ACS Photonics}, abstract = {The discrimination of enantiomers is crucial in biochemistry. However, chiral sensing faces significant limitations due to inherently weak chiroptical signals. Nanophotonics is a promising solution to enhance sensitivity thanks to increased optical chirality maximized by strong electric and magnetic fields. Metallic and dielectric nanoparticles can separately provide electric and magnetic resonances. Here we propose their synergistic combination in hybrid metal\textendashdielectric nanostructures to exploit their dual character for superchiral fields beyond the limits of single particles. For optimal optical chirality, in addition to maximization of the resonance strength, the resonances must spectrally coincide. Simultaneously, their electric and magnetic fields must be parallel and π/2 out of phase and spatially overlap. We demonstrate that the interplay between the strength of the resonances and these optimal conditions constrains the attainable optical chirality in resonant systems. Starting from a simple symmetric nanodimer, we derive closed-form expressions elucidating its fundamental limits of optical chirality. Building on the trade-offs of different classes of dimers, we then suggest an asymmetric dual dimer based on realistic materials. These dual nanoresonators provide strong and decoupled electric and magnetic resonances together with optimal conditions for chiral fields. Finally, we introduce more complex dual building blocks for a metasurface with a record 300-fold enhancement of local optical chirality in nanoscale gaps, enabling circular dichroism enhancement by a factor of 20. By combining analytical insight and practical designs, our results put forward hybrid resonators to increase chiral sensitivity, particularly for small molecular quantities.}, keywords = {Foundry Organic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close The discrimination of enantiomers is crucial in biochemistry. However, chiral sensing faces significant limitations due to inherently weak chiroptical signals. Nanophotonics is a promising solution to enhance sensitivity thanks to increased optical chirality maximized by strong electric and magnetic fields. Metallic and dielectric nanoparticles can separately provide electric and magnetic resonances. Here we propose their synergistic combination in hybrid metal–dielectric nanostructures to exploit their dual character for superchiral fields beyond the limits of single particles. For optimal optical chirality, in addition to maximization of the resonance strength, the resonances must spectrally coincide. Simultaneously, their electric and magnetic fields must be parallel and π/2 out of phase and spatially overlap. We demonstrate that the interplay between the strength of the resonances and these optimal conditions constrains the attainable optical chirality in resonant systems. Starting from a simple symmetric nanodimer, we derive closed-form expressions elucidating its fundamental limits of optical chirality. Building on the trade-offs of different classes of dimers, we then suggest an asymmetric dual dimer based on realistic materials. These dual nanoresonators provide strong and decoupled electric and magnetic resonances together with optimal conditions for chiral fields. Finally, we introduce more complex dual building blocks for a metasurface with a record 300-fold enhancement of local optical chirality in nanoscale gaps, enabling circular dichroism enhancement by a factor of 20. By combining analytical insight and practical designs, our results put forward hybrid resonators to increase chiral sensitivity, particularly for small molecular quantities. Close https://doi.org/10.1021/acsphotonics.1c00311 doi:10.1021/acsphotonics.1c00311 Close
250.	S Stegmaier, R Schierholz, I Povstugar, J Barthel, S P Rittmeyer, S Yu, S Wengert, S Rostami, H Kungl, K Reuter, R-A Eichel, C Scheurer Nano-Scale Complexions Facilitate Li Dendrite-Free Operation in LATP Solid-State Electrolyte Journal Article Advanced Energy Materials, n/a (n/a), pp. 2100707, 2021, ISSN: 1614-6832. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Nano-Scale Complexions Facilitate Li Dendrite-Free Operation in LATP Solid-State Electrolyte}, author = {S Stegmaier and R Schierholz and I Povstugar and J Barthel and S P Rittmeyer and S Yu and S Wengert and S Rostami and H Kungl and K Reuter and R-A Eichel and C Scheurer}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202100707}, doi = {https://doi.org/10.1002/aenm.202100707}, issn = {1614-6832}, year = {2021}, date = {2021-05-28}, journal = {Advanced Energy Materials}, volume = {n/a}, number = {n/a}, pages = {2100707}, abstract = {Abstract Dendrite formation and growth remains a major obstacle toward high-performance all solid-state batteries using Li metal anodes. The ceramic Li(1+x)Al(x)Ti(2−x)(PO4)3 (LATP) solid-state electrolyte shows a higher than expected stability against electrochemical decomposition despite a bulk electronic conductivity that exceeds a recently postulated threshold for dendrite-free operation. Here, transmission electron microscopy, atom probe tomography, and first-principles based simulations are combined to establish atomistic structural models of glass-amorphous LATP grain boundaries. These models reveal a nanometer-thin complexion layer that encapsulates the crystalline grains. The distinct composition of this complexion constitutes a sizable electronic impedance. Rather than fulfilling macroscopic bulk measures of ionic and electronic conduction, LATP might thus gain the capability to suppress dendrite nucleation by sufficient local separation of charge carriers at the nanoscale.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Abstract Dendrite formation and growth remains a major obstacle toward high-performance all solid-state batteries using Li metal anodes. The ceramic Li(1+x)Al(x)Ti(2−x)(PO4)3 (LATP) solid-state electrolyte shows a higher than expected stability against electrochemical decomposition despite a bulk electronic conductivity that exceeds a recently postulated threshold for dendrite-free operation. Here, transmission electron microscopy, atom probe tomography, and first-principles based simulations are combined to establish atomistic structural models of glass-amorphous LATP grain boundaries. These models reveal a nanometer-thin complexion layer that encapsulates the crystalline grains. The distinct composition of this complexion constitutes a sizable electronic impedance. Rather than fulfilling macroscopic bulk measures of ionic and electronic conduction, LATP might thus gain the capability to suppress dendrite nucleation by sufficient local separation of charge carriers at the nanoscale. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202100707 doi:https://doi.org/10.1002/aenm.202100707 Close
249.	M H Aufa, S A Watzele, S Hou, R W Haid, R M Kluge, A S Bandarenka, B Garlyyev Fast and accurate determination of the electroactive surface area of MnOx Journal Article Electrochimica Acta, 389 , pp. 138692, 2021, ISSN: 0013-4686. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Fast and accurate determination of the electroactive surface area of MnOx}, author = {M H Aufa and S A Watzele and S Hou and R W Haid and R M Kluge and A S Bandarenka and B Garlyyev}, url = {https://www.sciencedirect.com/science/article/pii/S0013468621009828}, doi = {https://doi.org/10.1016/j.electacta.2021.138692}, issn = {0013-4686}, year = {2021}, date = {2021-05-27}, journal = {Electrochimica Acta}, volume = {389}, pages = {138692}, abstract = {Manganese oxide (MnOx)-based materials are widely utilized in the field of electrocatalysis as bifunctional electrocatalysts for the oxygen reduction and evolution reactions. However, for an accurate assessment of their performance, the determination of their electrochemical active surface area (ECSA) is of paramount importance. So far, there is no fast and reproducible methodology. This article presents an easily applicable and affordable technique to determine the ECSA of MnOx accurately. The presented methodology makes use of the specific adsorption capacitance of reaction intermediates close to the onset potential of the oxygen evolution reaction. The electrochemical impedance spectroscopy is utilized to measure the specific adsorption capacitances at different potentials. Using MnOx thin-film electrodes, we determine the specific adsorption capacitances and present calibration values, which can be used for an accurate determination of the ECSA of different, for instance, nanostructured materials.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Manganese oxide (MnOx)-based materials are widely utilized in the field of electrocatalysis as bifunctional electrocatalysts for the oxygen reduction and evolution reactions. However, for an accurate assessment of their performance, the determination of their electrochemical active surface area (ECSA) is of paramount importance. So far, there is no fast and reproducible methodology. This article presents an easily applicable and affordable technique to determine the ECSA of MnOx accurately. The presented methodology makes use of the specific adsorption capacitance of reaction intermediates close to the onset potential of the oxygen evolution reaction. The electrochemical impedance spectroscopy is utilized to measure the specific adsorption capacitances at different potentials. Using MnOx thin-film electrodes, we determine the specific adsorption capacitances and present calibration values, which can be used for an accurate determination of the ECSA of different, for instance, nanostructured materials. Close https://www.sciencedirect.com/science/article/pii/S0013468621009828 doi:https://doi.org/10.1016/j.electacta.2021.138692 Close
248.	J Wang, B Wicher, A Méndez-Ardoy, X Li, G Pecastaings, T Buffeteau, D M Bassani, V Maurizot, I Huc Loading linear arrays of Cu(II) inside aromatic amide helices Journal Article Angewandte Chemie International Edition, n/a (n/a), 2021, ISSN: 1433-7851. Abstract \| Links \| Tags: Foundry Organic @article{, title = {Loading linear arrays of Cu(II) inside aromatic amide helices}, author = {J Wang and B Wicher and A M\'{e}ndez-Ardoy and X Li and G Pecastaings and T Buffeteau and D M Bassani and V Maurizot and I Huc}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202104734}, doi = {https://doi.org/10.1002/anie.202104734}, issn = {1433-7851}, year = {2021}, date = {2021-05-20}, journal = {Angewandte Chemie International Edition}, volume = {n/a}, number = {n/a}, abstract = {The very stable helices of 8-amino-2-quinolinecarboxylic acid oligoamides are shown to uptake Cu(II) ions in their cavity through deprotonation of their amide functions with minimal alteration of their shape, unlike most metallo-organic structures which generally much differ from their organic precursors. The outcome is the formation of intramolecular linear arrays of a defined number of Cu(II) centers (up to sixteen in this study) at a 3 r{A} distance, forming a molecular mimic of a metal wire completely surrounded by an organic sheath. The helices pack in the solid state so that the arrays of Cu(II) extend intermolecularly. Conductive-AFM and cyclic voltammetry suggest that electrons are transported throughout the metal-loaded helices in contrast with hole transport observed for analogous foldamers devoid of metal ions.}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close The very stable helices of 8-amino-2-quinolinecarboxylic acid oligoamides are shown to uptake Cu(II) ions in their cavity through deprotonation of their amide functions with minimal alteration of their shape, unlike most metallo-organic structures which generally much differ from their organic precursors. The outcome is the formation of intramolecular linear arrays of a defined number of Cu(II) centers (up to sixteen in this study) at a 3 Å distance, forming a molecular mimic of a metal wire completely surrounded by an organic sheath. The helices pack in the solid state so that the arrays of Cu(II) extend intermolecularly. Conductive-AFM and cyclic voltammetry suggest that electrons are transported throughout the metal-loaded helices in contrast with hole transport observed for analogous foldamers devoid of metal ions. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202104734 doi:https://doi.org/10.1002/anie.202104734 Close
247.	J Eichhorn, C-M Jiang, J K Cooper, I D Sharp, F M Toma Nanoscale Heterogeneities and Composition–Reactivity Relationships in Copper Vanadate Photoanodes Journal Article ACS Applied Materials & Interfaces, 13 (20), pp. 23575-23583, 2021, ISSN: 1944-8244. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Nanoscale Heterogeneities and Composition\textendashReactivity Relationships in Copper Vanadate Photoanodes}, author = {J Eichhorn and C-M Jiang and J K Cooper and I D Sharp and F M Toma}, url = {https://doi.org/10.1021/acsami.1c01848}, doi = {10.1021/acsami.1c01848}, issn = {1944-8244}, year = {2021}, date = {2021-05-17}, journal = {ACS Applied Materials & Interfaces}, volume = {13}, number = {20}, pages = {23575-23583}, abstract = {The photoelectrochemical performance of thin film photoelectrodes can be impacted by deviations from the stoichiometric composition, both at the macroscale and at the nanoscale. This issue is especially pronounced for the class of ternary compounds that are currently investigated for simultaneously achieving the optoelectronic characteristics and chemical stability required for solar fuel generation. Here, we combine macroscopic photoelectrochemical testing with atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM) to reveal relationships between photoelectrochemical activity, nanoscale morphology, and local chemical composition in copper vanadate (CVO) thin films as a model system. For films with varying Cu/(Cu + V) ratios around the ideal stoichiometry of stoiberite Cu5V2O10, AFM resolves submicrometer morphology variations, which correlate with variations of the Cu content resolved by STXM. Both stoichiometric and Cu-deficient films exhibit a clear photoresponse, which indicates electronic tolerance to reduced Cu content. While both films exhibit homogeneous O and V content, they are also characterized by local regions of Cu enrichment and depletion that extend beyond individual grains. By contrast, Cu-rich photoelectrodes exhibit a tendency toward CuO secondary phase formation and a significantly reduced photoelectrochemical activity, indicating a significantly poor electronic tolerance to Cu-enrichment. These findings highlight that the average film composition at the macroscale is insufficient for defining structure\textendashfunction relationships in complex ternary compounds. Rather, correlating microscopic variations in chemical composition to macroscopic photoelectrochemical performance provides insights into photocatalytic activity and stability that are otherwise not apparent from pure macroscopic characterization.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close The photoelectrochemical performance of thin film photoelectrodes can be impacted by deviations from the stoichiometric composition, both at the macroscale and at the nanoscale. This issue is especially pronounced for the class of ternary compounds that are currently investigated for simultaneously achieving the optoelectronic characteristics and chemical stability required for solar fuel generation. Here, we combine macroscopic photoelectrochemical testing with atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM) to reveal relationships between photoelectrochemical activity, nanoscale morphology, and local chemical composition in copper vanadate (CVO) thin films as a model system. For films with varying Cu/(Cu + V) ratios around the ideal stoichiometry of stoiberite Cu5V2O10, AFM resolves submicrometer morphology variations, which correlate with variations of the Cu content resolved by STXM. Both stoichiometric and Cu-deficient films exhibit a clear photoresponse, which indicates electronic tolerance to reduced Cu content. While both films exhibit homogeneous O and V content, they are also characterized by local regions of Cu enrichment and depletion that extend beyond individual grains. By contrast, Cu-rich photoelectrodes exhibit a tendency toward CuO secondary phase formation and a significantly reduced photoelectrochemical activity, indicating a significantly poor electronic tolerance to Cu-enrichment. These findings highlight that the average film composition at the macroscale is insufficient for defining structure–function relationships in complex ternary compounds. Rather, correlating microscopic variations in chemical composition to macroscopic photoelectrochemical performance provides insights into photocatalytic activity and stability that are otherwise not apparent from pure macroscopic characterization. Close https://doi.org/10.1021/acsami.1c01848 doi:10.1021/acsami.1c01848 Close
246.	M J Schilcher, P J Robinson, D J Abramovitch, L Z Tan, A M Rappe, D R Reichman, D A Egger The Significance of Polarons and Dynamic Disorder in Halide Perovskites Journal Article ACS Energy Letters, pp. 2162-2173, 2021. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {The Significance of Polarons and Dynamic Disorder in Halide Perovskites}, author = {M J Schilcher and P J Robinson and D J Abramovitch and L Z Tan and A M Rappe and D R Reichman and D A Egger}, url = {https://doi.org/10.1021/acsenergylett.1c00506}, doi = {10.1021/acsenergylett.1c00506}, year = {2021}, date = {2021-05-17}, journal = {ACS Energy Letters}, pages = {2162-2173}, abstract = {The development of halide perovskite semiconductors led to various technological breakthroughs in optoelectronics, in particular in the areas of photovoltaics and light-emitting diodes. Additionally, the study of their fundamental properties has uncovered intriguing puzzles that demand explanation. Polaronic effects associated with the coupling of electrons and holes to polar lattice vibrations are often invoked as a microscopic mechanism to explain various unusual experimental observations. While some form of polaronic behavior undoubtedly exists in these systems, several assumptions underlying standard models used to describe a polaron mechanism appear to be strongly violated in these materials. In this Perspective, we investigate the role of polaronic effects in halide perovskites and summarize signatures and failures of the polaron picture to explain physical characteristics of the materials. We highlight the importance of the complementary dynamic disorder concept that can rationalize various key properties of halide perovskites for which standard polaron and band-theory pictures of carrier transport fail.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close The development of halide perovskite semiconductors led to various technological breakthroughs in optoelectronics, in particular in the areas of photovoltaics and light-emitting diodes. Additionally, the study of their fundamental properties has uncovered intriguing puzzles that demand explanation. Polaronic effects associated with the coupling of electrons and holes to polar lattice vibrations are often invoked as a microscopic mechanism to explain various unusual experimental observations. While some form of polaronic behavior undoubtedly exists in these systems, several assumptions underlying standard models used to describe a polaron mechanism appear to be strongly violated in these materials. In this Perspective, we investigate the role of polaronic effects in halide perovskites and summarize signatures and failures of the polaron picture to explain physical characteristics of the materials. We highlight the importance of the complementary dynamic disorder concept that can rationalize various key properties of halide perovskites for which standard polaron and band-theory pictures of carrier transport fail. Close https://doi.org/10.1021/acsenergylett.1c00506 doi:10.1021/acsenergylett.1c00506 Close
245.	K Stallhofer, M Nuber, F Schüppel, S Thumser, H Iglev, De R Vivie-Riedle, W Zinth, H Dube Electronic and Geometric Characterization of TICT Formation in Hemithioindigo Photoswitches by Picosecond Infrared Spectroscopy Journal Article The Journal of Physical Chemistry A, 2021, ISSN: 1089-5639. Links \| Tags: Foundry Organic @article{, title = {Electronic and Geometric Characterization of TICT Formation in Hemithioindigo Photoswitches by Picosecond Infrared Spectroscopy}, author = {K Stallhofer and M Nuber and F Sch\"{u}ppel and S Thumser and H Iglev and De R Vivie-Riedle and W Zinth and H Dube}, url = {https://doi.org/10.1021/acs.jpca.1c02646}, doi = {10.1021/acs.jpca.1c02646}, issn = {1089-5639}, year = {2021}, date = {2021-05-14}, journal = {The Journal of Physical Chemistry A}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close https://doi.org/10.1021/acs.jpca.1c02646 doi:10.1021/acs.jpca.1c02646 Close
244.	L Zhu, Y Lin, K Liu, E Cortés, H Li, J Hu, A Yamaguchi, X Liu, M Miyauchi, J Fu, M Liu Tuning the intermediate reaction barriers by a CuPd catalyst to improve the selectivity of CO2 electroreduction to C2 products Journal Article Chinese Journal of Catalysis, 42 (9), pp. 1500-1508, 2021, ISSN: 1872-2067. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Tuning the intermediate reaction barriers by a CuPd catalyst to improve the selectivity of CO2 electroreduction to C2 products}, author = {L Zhu and Y Lin and K Liu and E Cort\'{e}s and H Li and J Hu and A Yamaguchi and X Liu and M Miyauchi and J Fu and M Liu}, url = {https://www.sciencedirect.com/science/article/pii/S1872206720637548}, doi = {https://doi.org/10.1016/S1872-2067(20)63754-8}, issn = {1872-2067}, year = {2021}, date = {2021-05-12}, journal = {Chinese Journal of Catalysis}, volume = {42}, number = {9}, pages = {1500-1508}, abstract = {Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity. Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon products. However, Cu exhibits an unfavorable activity and selectivity for the generation of C2 products because of the insufficient amount of CO* provided for the C-C coupling. Based on the strong CO2 adsorption and ultrafast reaction kinetics of CO* formation on Pd, an intimate CuPd(100) interface was designed to lower the intermediate reaction barriers and improve the efficiency of C2 product formation. Density functional theory (DFT) calculations showed that the CuPd(100) interface enhanced the CO2 adsorption and decreased the CO2* hydrogenation energy barrier, which was beneficial for the C-C coupling. The potential-determining step (PDS) barrier of CO2 to C2 products on the CuPd(100) interface was 0.61 eV, which was lower than that on Cu(100) (0.72 eV). Encouraged by the DFT calculation results, the CuPd(100) interface catalyst was prepared by a facile chemical solution method and characterized by transmission electron microscopy. CO2 temperature-programmed desorption and gas sensor experiments further confirmed the enhancement of the CO2 adsorption and CO2* hydrogenation ability of the CuPd(100) interface catalyst. Specifically, the obtained CuPd(100) interface catalyst exhibited a C2 Faradaic efficiency of 50.3% ± 1.2% at −1.4 VRHE in 0.1 M KHCO3, which was 2.1 times higher than that of the Cu catalyst (23.6% ± 1.5%). This study provides the basis for the rational design of Cu-based electrocatalysts for the generation of multicarbon products by fine-tuning the intermediate reaction barriers.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Electrochemical CO2 reduction is a promising strategy for the utilization of CO2 and intermittent excess electricity. Cu is the only single metal catalyst that can electrochemically convert CO2 into multicarbon products. However, Cu exhibits an unfavorable activity and selectivity for the generation of C2 products because of the insufficient amount of CO* provided for the C-C coupling. Based on the strong CO2 adsorption and ultrafast reaction kinetics of CO* formation on Pd, an intimate CuPd(100) interface was designed to lower the intermediate reaction barriers and improve the efficiency of C2 product formation. Density functional theory (DFT) calculations showed that the CuPd(100) interface enhanced the CO2 adsorption and decreased the CO2* hydrogenation energy barrier, which was beneficial for the C-C coupling. The potential-determining step (PDS) barrier of CO2 to C2 products on the CuPd(100) interface was 0.61 eV, which was lower than that on Cu(100) (0.72 eV). Encouraged by the DFT calculation results, the CuPd(100) interface catalyst was prepared by a facile chemical solution method and characterized by transmission electron microscopy. CO2 temperature-programmed desorption and gas sensor experiments further confirmed the enhancement of the CO2 adsorption and CO2* hydrogenation ability of the CuPd(100) interface catalyst. Specifically, the obtained CuPd(100) interface catalyst exhibited a C2 Faradaic efficiency of 50.3% ± 1.2% at −1.4 VRHE in 0.1 M KHCO3, which was 2.1 times higher than that of the Cu catalyst (23.6% ± 1.5%). This study provides the basis for the rational design of Cu-based electrocatalysts for the generation of multicarbon products by fine-tuning the intermediate reaction barriers. Close https://www.sciencedirect.com/science/article/pii/S1872206720637548 doi:https://doi.org/10.1016/S1872-2067(20)63754-8 Close
243.	T Debnath, D Sarker, H Huang, Z-K Han, A Dey, L Polavarapu, S V Levchenko, J Feldmann Coherent vibrational dynamics reveals lattice anharmonicity in organic–inorganic halide perovskite nanocrystals Journal Article Nature Communications, 12 (1), pp. 2629, 2021, ISSN: 2041-1723. Abstract \| Links \| Tags: Foundry Inorganic, Foundry Organic @article{, title = {Coherent vibrational dynamics reveals lattice anharmonicity in organic\textendashinorganic halide perovskite nanocrystals}, author = {T Debnath and D Sarker and H Huang and Z-K Han and A Dey and L Polavarapu and S V Levchenko and J Feldmann}, url = {https://doi.org/10.1038/s41467-021-22934-2}, doi = {10.1038/s41467-021-22934-2}, issn = {2041-1723}, year = {2021}, date = {2021-05-11}, journal = {Nature Communications}, volume = {12}, number = {1}, pages = {2629}, abstract = {The halide ions of organic-inorganic hybrid perovskites can strongly influence the interaction between the central organic moiety and the inorganic metal halide octahedral units and thus their lattice vibrations. Here, we report the halide-ion-dependent vibrational coherences in formamidinium lead halide (FAPbX3, X = Br, I) perovskite nanocrystals (PNCs) via the combination of femtosecond pump\textendashprobe spectroscopy and density functional theory calculations. We find that the FAPbX3 PNCs generate halide-dependent coherent vibronic wave packets upon above-bandgap non-resonant excitation. More importantly, we observe several higher harmonics of the fundamental modes for FAPbI3 PNCs as compared to FAPbBr3 PNCs. This is likely due to the weaker interaction between the central FA moiety and the inorganic cage for FAPbI3 PNCs, and thus the PbI64− unit can vibrate more freely. This weakening reveals the intrinsic anharmonicity in the Pb-I framework, and thus facilitating the energy transfer into overtone and combination bands. These findings not only unveil the superior stability of Br\textendashbased PNCs over I\textendashbased PNCs but are also important for a better understanding of their electronic and polaronic properties.}, keywords = {Foundry Inorganic, Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close The halide ions of organic-inorganic hybrid perovskites can strongly influence the interaction between the central organic moiety and the inorganic metal halide octahedral units and thus their lattice vibrations. Here, we report the halide-ion-dependent vibrational coherences in formamidinium lead halide (FAPbX3, X = Br, I) perovskite nanocrystals (PNCs) via the combination of femtosecond pump–probe spectroscopy and density functional theory calculations. We find that the FAPbX3 PNCs generate halide-dependent coherent vibronic wave packets upon above-bandgap non-resonant excitation. More importantly, we observe several higher harmonics of the fundamental modes for FAPbI3 PNCs as compared to FAPbBr3 PNCs. This is likely due to the weaker interaction between the central FA moiety and the inorganic cage for FAPbI3 PNCs, and thus the PbI64− unit can vibrate more freely. This weakening reveals the intrinsic anharmonicity in the Pb-I framework, and thus facilitating the energy transfer into overtone and combination bands. These findings not only unveil the superior stability of Br–based PNCs over I–based PNCs but are also important for a better understanding of their electronic and polaronic properties. Close https://doi.org/10.1038/s41467-021-22934-2 doi:10.1038/s41467-021-22934-2 Close
242.	L Katzenmeier, L Carstensen, S J Schaper, P Müller-Buschbaum, A S Bandarenka Characterization and Quantification of Depletion and Accumulation Layers in Solid-State Li+-Conducting Electrolytes Using In Situ Spectroscopic Ellipsometry Journal Article Advanced Materials, pp. e2100585, 2021, ISSN: 0935-9648. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Characterization and Quantification of Depletion and Accumulation Layers in Solid-State Li+-Conducting Electrolytes Using In Situ Spectroscopic Ellipsometry}, author = {L Katzenmeier and L Carstensen and S J Schaper and P M\"{u}ller-Buschbaum and A S Bandarenka}, url = {http://europepmc.org/abstract/MED/33955614 https://doi.org/10.1002/adma.202100585}, doi = {10.1002/adma.202100585}, issn = {0935-9648}, year = {2021}, date = {2021-05-06}, journal = {Advanced Materials}, pages = {e2100585}, abstract = {The future of mobility depends on the development of next-generation battery technologies, such as all-solid-state batteries. As the ionic conductivity of solid Li<sup>+</sup> -conductors can, in some cases, approach that of liquid electrolytes, a significant remaining barrier faced by solid-state electrolytes (SSEs) is the interface formed at the anode and cathode materials, with chemical instability and physical resistances arising. The physical properties of space charge layers (SCLs), a widely discussed phenomenon in SSEs, are still unclear. In this work, spectroscopic ellipsometry is used to characterize the accumulation and depletion layers. An optical model is developed to quantify their thicknesses and corresponding concentration changes. It is shown that the Li<sup>+</sup> -depleted layer (≈190 nm at 1 V) is thinner than the accumulation layer (≈320 nm at 1 V) in a glassy lithium-ion-conducting glass ceramic electrolyte (a trademark of Ohara Corporation). The in situ approach combining electrochemistry and optics resolves the ambiguities around SCL formation. It opens up a wide field of optical measurements on SSEs, allowing various experimental studies in the future.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close The future of mobility depends on the development of next-generation battery technologies, such as all-solid-state batteries. As the ionic conductivity of solid Li<sup>+</sup> -conductors can, in some cases, approach that of liquid electrolytes, a significant remaining barrier faced by solid-state electrolytes (SSEs) is the interface formed at the anode and cathode materials, with chemical instability and physical resistances arising. The physical properties of space charge layers (SCLs), a widely discussed phenomenon in SSEs, are still unclear. In this work, spectroscopic ellipsometry is used to characterize the accumulation and depletion layers. An optical model is developed to quantify their thicknesses and corresponding concentration changes. It is shown that the Li<sup>+</sup> -depleted layer (≈190 nm at 1 V) is thinner than the accumulation layer (≈320 nm at 1 V) in a glassy lithium-ion-conducting glass ceramic electrolyte (a trademark of Ohara Corporation). The in situ approach combining electrochemistry and optics resolves the ambiguities around SCL formation. It opens up a wide field of optical measurements on SSEs, allowing various experimental studies in the future. Close http://europepmc.org/abstract/MED/33955614 https://doi.org/10.1002/adma.202100585 doi:10.1002/adma.202100585 Close
241.	J Lenz, A M Seiler, F R Geisenhof, F Winterer, K Watanabe, T Taniguchi, R T Weitz High-Performance Vertical Organic Transistors of Sub-5 nm Channel Length Journal Article Nano Letters, 2021, ISSN: 1530-6984. Abstract \| Links \| Tags: Foundry Organic @article{, title = {High-Performance Vertical Organic Transistors of Sub-5 nm Channel Length}, author = {J Lenz and A M Seiler and F R Geisenhof and F Winterer and K Watanabe and T Taniguchi and R T Weitz}, url = {https://doi.org/10.1021/acs.nanolett.1c01144}, doi = {10.1021/acs.nanolett.1c01144}, issn = {1530-6984}, year = {2021}, date = {2021-05-06}, journal = {Nano Letters}, abstract = {Miniaturization of electronic circuits increases their overall performance. So far, electronics based on organic semiconductors has not played an important role in the miniaturization race. Here, we show the fabrication of liquid electrolyte gated vertical organic field effect transistors with channel lengths down to 2.4 nm. These ultrashort channel lengths are enabled by using insulating hexagonal boron nitride with atomically precise thickness and flatness as a spacer separating the vertically aligned source and drain electrodes. The transistors reveal promising electrical characteristics with output current densities of up to 2.95 MA cm\textendash2 at −0.4 V bias, on\textendashoff ratios of up to 106, a steep subthreshold swing of down to 65 mV dec\textendash1 and a transconductance of up to 714 S m\textendash1. Realizing channel lengths in the sub-5 nm regime and operation voltages down to 100 μV proves the potential of organic semiconductors for future highly integrated or low power electronics.}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close Miniaturization of electronic circuits increases their overall performance. So far, electronics based on organic semiconductors has not played an important role in the miniaturization race. Here, we show the fabrication of liquid electrolyte gated vertical organic field effect transistors with channel lengths down to 2.4 nm. These ultrashort channel lengths are enabled by using insulating hexagonal boron nitride with atomically precise thickness and flatness as a spacer separating the vertically aligned source and drain electrodes. The transistors reveal promising electrical characteristics with output current densities of up to 2.95 MA cm–2 at −0.4 V bias, on–off ratios of up to 106, a steep subthreshold swing of down to 65 mV dec–1 and a transconductance of up to 714 S m–1. Realizing channel lengths in the sub-5 nm regime and operation voltages down to 100 μV proves the potential of organic semiconductors for future highly integrated or low power electronics. Close https://doi.org/10.1021/acs.nanolett.1c01144 doi:10.1021/acs.nanolett.1c01144 Close
240.	F Winterer, L S Walter, J Lenz, S Seebauer, Y Tong, L Polavarapu, R T Weitz Charge Traps in All‐Inorganic CsPbBr3 Perovskite Nanowire Field‐Effect Phototransistors Journal Article Advanced Electronic Materials, pp. 2100105, 2021, ISSN: 2199-160X. Tags: Foundry Inorganic @article{, title = {Charge Traps in All‐Inorganic CsPbBr3 Perovskite Nanowire Field‐Effect Phototransistors}, author = {F Winterer and L S Walter and J Lenz and S Seebauer and Y Tong and L Polavarapu and R T Weitz}, issn = {2199-160X}, year = {2021}, date = {2021-05-06}, journal = {Advanced Electronic Materials}, pages = {2100105}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close
239.	K Stallhofer, M Nuber, D Cortecchia, A Bruno, R Kienberger, F Deschler, C Soci, H Iglev Picosecond Charge Localization Dynamics in CH3NH3PbI3 Perovskite Probed by Infrared-Activated Vibrations Journal Article The Journal of Physical Chemistry Letters, pp. 4428-4433, 2021. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Picosecond Charge Localization Dynamics in CH3NH3PbI3 Perovskite Probed by Infrared-Activated Vibrations}, author = {K Stallhofer and M Nuber and D Cortecchia and A Bruno and R Kienberger and F Deschler and C Soci and H Iglev}, url = {https://doi.org/10.1021/acs.jpclett.1c00935}, doi = {10.1021/acs.jpclett.1c00935}, year = {2021}, date = {2021-05-05}, journal = {The Journal of Physical Chemistry Letters}, pages = {4428-4433}, abstract = {Hybrid metal halide perovskites exhibit well-defined semiconducting properties and efficient optoelectronic performance considering their soft crystal structure and low-energy lattice motions. The response of such a crystal lattice to light-induced charges is a fundamental question, for which experimental insight into ultrafast time scales is still sought. Here, we use infrared-activated vibrations (IRAV) of the organic components within the hybrid perovskite lattice as a sensitive probe for local structural reorganizations after photoexcitation, with femtosecond resolution. We find that the IRAV signal response shows a delayed rise of about 3 ps and subsequent decay of pronounced monomolecular character, distinguishing it from absorption associated with free carriers. We interpret our results as a two-step carrier localization process. Initially, carriers localize transiently in local energy minima formed by lattice fluctuations. A subpopulation of these can then fall into deeper trapped states over picoseconds, likely due to local reorganization of the organic molecules surrounding the carriers.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Hybrid metal halide perovskites exhibit well-defined semiconducting properties and efficient optoelectronic performance considering their soft crystal structure and low-energy lattice motions. The response of such a crystal lattice to light-induced charges is a fundamental question, for which experimental insight into ultrafast time scales is still sought. Here, we use infrared-activated vibrations (IRAV) of the organic components within the hybrid perovskite lattice as a sensitive probe for local structural reorganizations after photoexcitation, with femtosecond resolution. We find that the IRAV signal response shows a delayed rise of about 3 ps and subsequent decay of pronounced monomolecular character, distinguishing it from absorption associated with free carriers. We interpret our results as a two-step carrier localization process. Initially, carriers localize transiently in local energy minima formed by lattice fluctuations. A subpopulation of these can then fall into deeper trapped states over picoseconds, likely due to local reorganization of the organic molecules surrounding the carriers. Close https://doi.org/10.1021/acs.jpclett.1c00935 doi:10.1021/acs.jpclett.1c00935 Close
238.	F Zoller, S Häringer, D Böhm, J Luxa, Z Sofer, D Fattakhova-Rohlfing Carbonaceous Oxygen Evolution Reaction Catalysts: From Defect and Doping-Induced Activity over Hybrid Compounds to Ordered Framework Structures Journal Article Small, pp. e2007484, 2021, ISSN: 1613-6810. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Liquid @article{, title = {Carbonaceous Oxygen Evolution Reaction Catalysts: From Defect and Doping-Induced Activity over Hybrid Compounds to Ordered Framework Structures}, author = {F Zoller and S H\"{a}ringer and D B\"{o}hm and J Luxa and Z Sofer and D Fattakhova-Rohlfing}, doi = {10.1002/smll.202007484}, issn = {1613-6810}, year = {2021}, date = {2021-05-04}, journal = {Small}, pages = {e2007484}, abstract = {Oxygen evolution reaction (OER) is expected to be of great importance for the future energy conversion and storage in form of hydrogen by water electrolysis. Besides the traditional noble-metal or transition metal oxide-based catalysts, carbonaceous electrocatalysts are of great interest due to their huge structural and compositional variety and unrestricted abundance. This review provides a summary of recent advances in the field of carbon-based OER catalysts ranging from "pure" or unintentionally doped carbon allotropes over heteroatom-doped carbonaceous materials and carbon/transition metal compounds to metal oxide composites where the role of carbon is mainly assigned to be a conductive support. Furthermore, the review discusses the recent developments in the field of ordered carbon framework structures (metal organic framework and covalent organic framework structures) that potentially allow a rational design of heteroatom-doped 3D porous structures with defined composition and spatial arrangement of doping atoms to deepen the understanding on the OER mechanism on carbonaceous structures in the future. Besides introducing the structural and compositional origin of electrochemical activity, the review discusses the mechanism of the catalytic activity of carbonaceous materials, their stability under OER conditions, and potential synergistic effects in combination with metal (or metal oxide) co-catalysts.}, keywords = {Foundry Inorganic, Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Oxygen evolution reaction (OER) is expected to be of great importance for the future energy conversion and storage in form of hydrogen by water electrolysis. Besides the traditional noble-metal or transition metal oxide-based catalysts, carbonaceous electrocatalysts are of great interest due to their huge structural and compositional variety and unrestricted abundance. This review provides a summary of recent advances in the field of carbon-based OER catalysts ranging from "pure" or unintentionally doped carbon allotropes over heteroatom-doped carbonaceous materials and carbon/transition metal compounds to metal oxide composites where the role of carbon is mainly assigned to be a conductive support. Furthermore, the review discusses the recent developments in the field of ordered carbon framework structures (metal organic framework and covalent organic framework structures) that potentially allow a rational design of heteroatom-doped 3D porous structures with defined composition and spatial arrangement of doping atoms to deepen the understanding on the OER mechanism on carbonaceous structures in the future. Besides introducing the structural and compositional origin of electrochemical activity, the review discusses the mechanism of the catalytic activity of carbonaceous materials, their stability under OER conditions, and potential synergistic effects in combination with metal (or metal oxide) co-catalysts. Close doi:10.1002/smll.202007484 Close
237.	I Kamińska, J Bohlen, R Yaadav, P Schüler, M Raab, T Schröder, J Zähringer, K Zielonka, S Krause, P Tinnefeld Graphene Energy Transfer for Single-Molecule Biophysics, Biosensing, and Super-Resolution Microscopy Journal Article Advanced Materials, n/a (n/a), pp. 2101099, 2021, ISSN: 0935-9648. Abstract \| Links \| Tags: Foundry Organic @article{, title = {Graphene Energy Transfer for Single-Molecule Biophysics, Biosensing, and Super-Resolution Microscopy}, author = {I Kami\'{n}ska and J Bohlen and R Yaadav and P Sch\"{u}ler and M Raab and T Schr\"{o}der and J Z\"{a}hringer and K Zielonka and S Krause and P Tinnefeld}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202101099}, doi = {https://doi.org/10.1002/adma.202101099}, issn = {0935-9648}, year = {2021}, date = {2021-05-03}, journal = {Advanced Materials}, volume = {n/a}, number = {n/a}, pages = {2101099}, abstract = {Abstract Graphene is considered a game-changing material, especially for its mechanical and electrical properties. This work exploits that graphene is almost transparent but quenches fluorescence in a range up to ≈40 nm. Graphene as a broadband and unbleachable energy-transfer acceptor without labeling, is used to precisely determine the height of molecules with respect to graphene, to visualize the dynamics of DNA nanostructures, and to determine the orientation of F\"{o}rster-type resonance energy transfer (FRET) pairs. Using DNA origami nanopositioners, biosensing, single-molecule tracking, and DNA PAINT super-resolution with <3 nm z-resolution are demonstrated. The range of examples shows the potential of graphene-on-glass coverslips as a versatile platform for single-molecule biophysics, biosensing, and super-resolution microscopy.}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close Abstract Graphene is considered a game-changing material, especially for its mechanical and electrical properties. This work exploits that graphene is almost transparent but quenches fluorescence in a range up to ≈40 nm. Graphene as a broadband and unbleachable energy-transfer acceptor without labeling, is used to precisely determine the height of molecules with respect to graphene, to visualize the dynamics of DNA nanostructures, and to determine the orientation of Förster-type resonance energy transfer (FRET) pairs. Using DNA origami nanopositioners, biosensing, single-molecule tracking, and DNA PAINT super-resolution with <3 nm z-resolution are demonstrated. The range of examples shows the potential of graphene-on-glass coverslips as a versatile platform for single-molecule biophysics, biosensing, and super-resolution microscopy. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202101099 doi:https://doi.org/10.1002/adma.202101099 Close
236.	L Hüttenhofer, A Tittl, L Kühner, E Cortés, S A Maier Anapole-Assisted Absorption Engineering in Arrays of Coupled Amorphous Gallium Phosphide Nanodisks Journal Article ACS Photonics, 2021. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Anapole-Assisted Absorption Engineering in Arrays of Coupled Amorphous Gallium Phosphide Nanodisks}, author = {L H\"{u}ttenhofer and A Tittl and L K\"{u}hner and E Cort\'{e}s and S A Maier}, url = {https://doi.org/10.1021/acsphotonics.1c00238}, doi = {10.1021/acsphotonics.1c00238}, year = {2021}, date = {2021-04-26}, journal = {ACS Photonics}, abstract = {Broadband solar light harvesting plays a crucial role for efficient energy conversion. Anapole excitations and associated absorption engineering in dielectric nanoresonators are a focus of nanophotonic research due to the intricate combination of nonradiating modes and strong electromagnetic field confinement in the underlying material. The arising high field strengths are used for enhanced second-harmonic generation and photocatalysis, where devices require large areas with closely spaced nanoresonators for sizable photonic yields. However, most anapole studies have so far been carried out at the single-particle level, neglecting the influence of anapole\textendashanapole interactions. Here, we present a systematic study of coupling mechanisms in rectangular arrays of amorphous GaP nanodisks that support anapole excitations at 600 nm, which is within the lossy spectral regime of the material. Our experimental findings show that maximum visible light extinction by the array and maximum absorption in the GaP are not achieved by the densest packing of resonators. Counterintuitively, increasing the array periodicities such that collective effects spectrally overlap with the anapole excitation of a single particle leads to an absorption enhancement of up to 300% compared to a single disk. An analysis of coupling in one- and two-dimensional arrays with polarization-dependent measurements and numerical simulations allows us to discriminate between coupling interactions parallel and perpendicular to the polarization axis and evaluate their strengths. Utilizing a multipolar decomposition of excitations in single nanodisks embedded in one-dimensional arrays, we can attribute the coupling to enhanced electric and toroidal dipoles under variation of the interparticle spacing. Our results provide a fundamental understanding of tailored light absorption in coupled anapole resonators and reveal important design guidelines for advanced metasurface approaches in a wide range of energy conversion applications.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Broadband solar light harvesting plays a crucial role for efficient energy conversion. Anapole excitations and associated absorption engineering in dielectric nanoresonators are a focus of nanophotonic research due to the intricate combination of nonradiating modes and strong electromagnetic field confinement in the underlying material. The arising high field strengths are used for enhanced second-harmonic generation and photocatalysis, where devices require large areas with closely spaced nanoresonators for sizable photonic yields. However, most anapole studies have so far been carried out at the single-particle level, neglecting the influence of anapole–anapole interactions. Here, we present a systematic study of coupling mechanisms in rectangular arrays of amorphous GaP nanodisks that support anapole excitations at 600 nm, which is within the lossy spectral regime of the material. Our experimental findings show that maximum visible light extinction by the array and maximum absorption in the GaP are not achieved by the densest packing of resonators. Counterintuitively, increasing the array periodicities such that collective effects spectrally overlap with the anapole excitation of a single particle leads to an absorption enhancement of up to 300% compared to a single disk. An analysis of coupling in one- and two-dimensional arrays with polarization-dependent measurements and numerical simulations allows us to discriminate between coupling interactions parallel and perpendicular to the polarization axis and evaluate their strengths. Utilizing a multipolar decomposition of excitations in single nanodisks embedded in one-dimensional arrays, we can attribute the coupling to enhanced electric and toroidal dipoles under variation of the interparticle spacing. Our results provide a fundamental understanding of tailored light absorption in coupled anapole resonators and reveal important design guidelines for advanced metasurface approaches in a wide range of energy conversion applications. Close https://doi.org/10.1021/acsphotonics.1c00238 doi:10.1021/acsphotonics.1c00238 Close
235.	S Akel, M A Sharif, R Al-Esseili, M A Al-Wahish, H A Hodali, P Müller-Buschbaum, L Schmidt-Mende, M Al-Hussein Photovoltaic Cells Based on Ternary P3HT:PCBM:Ruthenium(II) Complex Bearing 8-(diphenylphosphino)quinoline Active Layer Journal Article Colloids and Surfaces A: Physicochemical and Engineering Aspects, pp. 126685, 2021, ISSN: 0927-7757. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Photovoltaic Cells Based on Ternary P3HT:PCBM:Ruthenium(II) Complex Bearing 8-(diphenylphosphino)quinoline Active Layer}, author = {S Akel and M A Sharif and R Al-Esseili and M A Al-Wahish and H A Hodali and P M\"{u}ller-Buschbaum and L Schmidt-Mende and M Al-Hussein}, url = {https://www.sciencedirect.com/science/article/pii/S0927775721005549}, doi = {https://doi.org/10.1016/j.colsurfa.2021.126685}, issn = {0927-7757}, year = {2021}, date = {2021-04-24}, journal = {Colloids and Surfaces A: Physicochemical and Engineering Aspects}, pages = {126685}, abstract = {ABSTRACT Optical, morphological and photovoltaic properties are investigated for ternary solar cells containing a traditional poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric-acid-methyl ester (P3HT:PCBM) bulkheterojunction (BHJ) active layer modified with different concentrations of a novel ruthenium complex [Ru(N-P)2(O-O)], where N-P abbreviates 8-(diphenylphosphino)quinolone and O-O = oxalate dianion. At a low concentration of the Ru-complex (2.5wt. %) the device efficiency is improved by 50% compared with the reference binary devices at ambient conditions. This substantial efficiency enhancement is attributed to the role of the Ru-complex in improving light absorption over a wavelength range of (295-800nm) in combination with a better matching of the energy levels of the ternary blend system. Moreover, at low concentration, the Ru-complex has a positive impact on the morphology of the active layer in the device. The inclusion of Ru-complex increases the P3HT crystallinity substantially with virtually no effect on the size and orientation of the crystalline lamellae. The enhancement in device efficiency becomes less pronounced with increasing the concentration of the Ru-complex due to the formation of several micron-size domains of [Ru(N-P)2(O-O)] in the ternary active layers. These large domains negatively affect the optical properties and morphology, thus inhibiting efficient charge generation and transport in the corresponding solar cells.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close ABSTRACT Optical, morphological and photovoltaic properties are investigated for ternary solar cells containing a traditional poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl-C61-butyric-acid-methyl ester (P3HT:PCBM) bulkheterojunction (BHJ) active layer modified with different concentrations of a novel ruthenium complex [Ru(N-P)2(O-O)], where N-P abbreviates 8-(diphenylphosphino)quinolone and O-O = oxalate dianion. At a low concentration of the Ru-complex (2.5wt. %) the device efficiency is improved by 50% compared with the reference binary devices at ambient conditions. This substantial efficiency enhancement is attributed to the role of the Ru-complex in improving light absorption over a wavelength range of (295-800nm) in combination with a better matching of the energy levels of the ternary blend system. Moreover, at low concentration, the Ru-complex has a positive impact on the morphology of the active layer in the device. The inclusion of Ru-complex increases the P3HT crystallinity substantially with virtually no effect on the size and orientation of the crystalline lamellae. The enhancement in device efficiency becomes less pronounced with increasing the concentration of the Ru-complex due to the formation of several micron-size domains of [Ru(N-P)2(O-O)] in the ternary active layers. These large domains negatively affect the optical properties and morphology, thus inhibiting efficient charge generation and transport in the corresponding solar cells. Close https://www.sciencedirect.com/science/article/pii/S0927775721005549 doi:https://doi.org/10.1016/j.colsurfa.2021.126685 Close
234.	H Zheng, D Li, C Ran, Q Zhong, L Song, Y Chen, P Müller-Buschbaum, W Huang Emerging Organic/Hybrid Photovoltaic Cells for Indoor Applications: Recent Advances and Perspectives Journal Article Solar RRL, n/a (n/a), pp. 2100042, 2021, ISSN: 2367-198X. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Emerging Organic/Hybrid Photovoltaic Cells for Indoor Applications: Recent Advances and Perspectives}, author = {H Zheng and D Li and C Ran and Q Zhong and L Song and Y Chen and P M\"{u}ller-Buschbaum and W Huang}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202100042}, doi = {https://doi.org/10.1002/solr.202100042}, issn = {2367-198X}, year = {2021}, date = {2021-04-23}, journal = {Solar RRL}, volume = {n/a}, number = {n/a}, pages = {2100042}, abstract = {Due to the continuous development and advances in the Internet of Things, wireless sensors, actuators for human−interactive machines, and indoor low-power devices require a continuous supply of energy. Photovoltaic cells working under indoor light are suitable candidates for charging these devices because of their high voltages (up to 5 V), low costs, and environmental friendliness. Herein, the research on organic photovoltaic, dye-sensitized, and perovskite cells in indoor photovoltaic applications with respect to the active layer, modified layer, and preparation process is summarized. The performance enhancement of indoor photovoltaic cells is outlined, including photoactive material selection, bandgap optimization, modification layer function, and device structure design, followed by the prospects and challenges of future developments in indoor photovoltaic cells. With this review an important perspective for the advancement of indoor photovoltaics is offered.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Due to the continuous development and advances in the Internet of Things, wireless sensors, actuators for human−interactive machines, and indoor low-power devices require a continuous supply of energy. Photovoltaic cells working under indoor light are suitable candidates for charging these devices because of their high voltages (up to 5 V), low costs, and environmental friendliness. Herein, the research on organic photovoltaic, dye-sensitized, and perovskite cells in indoor photovoltaic applications with respect to the active layer, modified layer, and preparation process is summarized. The performance enhancement of indoor photovoltaic cells is outlined, including photoactive material selection, bandgap optimization, modification layer function, and device structure design, followed by the prospects and challenges of future developments in indoor photovoltaic cells. With this review an important perspective for the advancement of indoor photovoltaics is offered. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/solr.202100042 doi:https://doi.org/10.1002/solr.202100042 Close
233.	R Lauenstein, S L Mader, H Derondeau, O Z Esezobor, M Block, A J Römer, C Jandl, E Riedle, V R I Kaila, J Hauer, E Thyrhaug, C R Hess The central role of the metal ion for photoactivity: Zn– vs. Ni–Mabiq Journal Article Chemical Science, 2021, ISSN: 2041-6520. Abstract \| Links \| Tags: Molecularly-Functionalized, Solid-Liquid @article{, title = {The central role of the metal ion for photoactivity: Zn\textendash vs. Ni\textendashMabiq}, author = {R Lauenstein and S L Mader and H Derondeau and O Z Esezobor and M Block and A J R\"{o}mer and C Jandl and E Riedle and V R I Kaila and J Hauer and E Thyrhaug and C R Hess}, url = {http://dx.doi.org/10.1039/D0SC06096H}, doi = {10.1039/D0SC06096H}, issn = {2041-6520}, year = {2021}, date = {2021-04-21}, journal = {Chemical Science}, abstract = {Photoredox catalysts are integral components of artificial photosystems, and have recently emerged as powerful tools for catalysing numerous organic reactions. However, the development of inexpensive and efficient earth-abundant photoredox catalysts remains a challenge. We here present the photochemical and photophysical properties of a Ni\textendashMabiq catalyst ([NiII(Mabiq)]OTf (1); Mabiq = 2-4:6-8-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)\textemdashand of a Zn-containing analogue ([ZnII(Mabiq)OTf] (2))\textemdashusing steady state and time resolved optical spectroscopy, time-dependent density functional theory (TDDFT) calculations, and reactivity studies. The Ni and Zn complexes exhibit similar absorption spectra, but markedly different photochemical properties. These differences arise because the excited states of 2 are ligand-localized, whereas metal-centered states account for the photoactivity of 1. The distinct properties of the Ni and Zn complexes are manifest in their behavior in the photo-driven aza-Henry reaction and oxidative coupling of methoxybenzylamine.}, keywords = {Molecularly-Functionalized, Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Photoredox catalysts are integral components of artificial photosystems, and have recently emerged as powerful tools for catalysing numerous organic reactions. However, the development of inexpensive and efficient earth-abundant photoredox catalysts remains a challenge. We here present the photochemical and photophysical properties of a Ni–Mabiq catalyst ([NiII(Mabiq)]OTf (1); Mabiq = 2-4:6-8-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)—and of a Zn-containing analogue ([ZnII(Mabiq)OTf] (2))—using steady state and time resolved optical spectroscopy, time-dependent density functional theory (TDDFT) calculations, and reactivity studies. The Ni and Zn complexes exhibit similar absorption spectra, but markedly different photochemical properties. These differences arise because the excited states of 2 are ligand-localized, whereas metal-centered states account for the photoactivity of 1. The distinct properties of the Ni and Zn complexes are manifest in their behavior in the photo-driven aza-Henry reaction and oxidative coupling of methoxybenzylamine. Close http://dx.doi.org/10.1039/D0SC06096H doi:10.1039/D0SC06096H Close
232.	L V Besteiro, E Cortés, S Ishii, P Narang, R F Oulton Hot electron physics and applications Journal Article Journal of Applied Physics, 129 (15), pp. 150401, 2021. Links \| Tags: Solid-Liquid, Solid-Solid @article{, title = {Hot electron physics and applications}, author = {L V Besteiro and E Cort\'{e}s and S Ishii and P Narang and R F Oulton}, url = {https://aip.scitation.org/doi/abs/10.1063/5.0050796}, doi = {10.1063/5.0050796}, year = {2021}, date = {2021-04-19}, journal = {Journal of Applied Physics}, volume = {129}, number = {15}, pages = {150401}, keywords = {Solid-Liquid, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close https://aip.scitation.org/doi/abs/10.1063/5.0050796 doi:10.1063/5.0050796 Close
231.	M Günther, D Blätte, A L Oechsle, S S Rivas, Yousefi A A Amin, P Müller-Buschbaum, T Bein, T Ameri Increasing Photostability of Inverted Nonfullerene Organic Solar Cells by Using Fullerene Derivative Additives Journal Article ACS Applied Materials & Interfaces, 2021, ISSN: 1944-8244. Abstract \| Links \| Tags: Foundry Organic, Molecularly Functionalized @article{, title = {Increasing Photostability of Inverted Nonfullerene Organic Solar Cells by Using Fullerene Derivative Additives}, author = {M G\"{u}nther and D Bl\"{a}tte and A L Oechsle and S S Rivas and Yousefi A A Amin and P M\"{u}ller-Buschbaum and T Bein and T Ameri}, url = {https://doi.org/10.1021/acsami.1c00700}, doi = {10.1021/acsami.1c00700}, issn = {1944-8244}, year = {2021}, date = {2021-04-16}, journal = {ACS Applied Materials & Interfaces}, abstract = {Organic solar cells (OSCs) recently achieved efficiencies of over 18% and are well on their way to practical applications, but still considerable stability issues need to be overcome. One major problem emerges from the electron transport material zinc oxide (ZnO), which is mainly used in the inverted device architecture and decomposes many high-performance nonfullerene acceptors due to its photocatalytic activity. In this work, we add three different fullerene derivatives\textemdashPC71BM, ICMA, and BisPCBM\textemdashto an inverted binary PBDB-TF:IT-4F system in order to suppress the photocatalytic degradation of IT-4F on ZnO via the radical scavenging abilities of the fullerenes. We demonstrate that the addition of 5% fullerene not only increases the performance of the binary PBDB-TF:IT-4F system but also significantly improves the device lifetime under UV illumination in an inert atmosphere. While the binary devices lose 20% of their initial efficiency after only 3 h, this time is increased fivefold for the most promising ternary devices with ICMA. We attribute this improvement to a reduced photocatalytic decomposition of IT-4F in the ternary system, which results in a decreased recombination. We propose that the added fullerenes protect the IT-4F by acting as a sacrificial reagent, thereby suppressing the trap state formation. Furthermore, we show that the protective effect of the most promising fullerene ICMA is transferable to two other binary systems PBDB-TF:BTP-4F and PTB7-Th:IT-4F. Importantly, this effect can also increase the air stability of PBDB-TF:IT-4F. This work demonstrates that the addition of fullerene derivatives is a transferable and straightforward strategy to improve the stability of OSCs.}, keywords = {Foundry Organic, Molecularly Functionalized}, pubstate = {published}, tppubtype = {article} } Close Organic solar cells (OSCs) recently achieved efficiencies of over 18% and are well on their way to practical applications, but still considerable stability issues need to be overcome. One major problem emerges from the electron transport material zinc oxide (ZnO), which is mainly used in the inverted device architecture and decomposes many high-performance nonfullerene acceptors due to its photocatalytic activity. In this work, we add three different fullerene derivatives—PC71BM, ICMA, and BisPCBM—to an inverted binary PBDB-TF:IT-4F system in order to suppress the photocatalytic degradation of IT-4F on ZnO via the radical scavenging abilities of the fullerenes. We demonstrate that the addition of 5% fullerene not only increases the performance of the binary PBDB-TF:IT-4F system but also significantly improves the device lifetime under UV illumination in an inert atmosphere. While the binary devices lose 20% of their initial efficiency after only 3 h, this time is increased fivefold for the most promising ternary devices with ICMA. We attribute this improvement to a reduced photocatalytic decomposition of IT-4F in the ternary system, which results in a decreased recombination. We propose that the added fullerenes protect the IT-4F by acting as a sacrificial reagent, thereby suppressing the trap state formation. Furthermore, we show that the protective effect of the most promising fullerene ICMA is transferable to two other binary systems PBDB-TF:BTP-4F and PTB7-Th:IT-4F. Importantly, this effect can also increase the air stability of PBDB-TF:IT-4F. This work demonstrates that the addition of fullerene derivatives is a transferable and straightforward strategy to improve the stability of OSCs. Close https://doi.org/10.1021/acsami.1c00700 doi:10.1021/acsami.1c00700 Close
230.	N G Hörmann, K Reuter Thermodynamic Cyclic Voltammograms: Peak Positions and Shapes Journal Article Journal of Physics: Condensed Matter, 2021, ISSN: 0953-8984. Tags: Solid-Solid @article{, title = {Thermodynamic Cyclic Voltammograms: Peak Positions and Shapes}, author = {N G H\"{o}rmann and K Reuter}, issn = {0953-8984}, year = {2021}, date = {2021-04-13}, journal = {Journal of Physics: Condensed Matter}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close
229.	S Krause, E Ploetz, J Bohlen, P Schüler, R Yaadav, F Selbach, F Steiner, I Kamińska, P Tinnefeld Graphene-on-Glass Preparation and Cleaning Methods Characterized by Single-Molecule DNA Origami Fluorescent Probes and Raman Spectroscopy Journal Article ACS Nano, 2021, ISSN: 1936-0851. Abstract \| Links \| Tags: Foundry Organic @article{, title = {Graphene-on-Glass Preparation and Cleaning Methods Characterized by Single-Molecule DNA Origami Fluorescent Probes and Raman Spectroscopy}, author = {S Krause and E Ploetz and J Bohlen and P Sch\"{u}ler and R Yaadav and F Selbach and F Steiner and I Kami\'{n}ska and P Tinnefeld}, url = {https://pubs.acs.org/doi/abs/10.1021/acsnano.0c08383}, doi = {10.1021/acsnano.0c08383}, issn = {1936-0851}, year = {2021}, date = {2021-04-09}, journal = {ACS Nano}, abstract = {Graphene exhibits outstanding fluorescence quenching properties that can become useful for biophysics and biosensing applications, but it remains challenging to harness these advantages due to the complex transfer procedure of chemical vapor deposition-grown graphene to glass coverslips and the low yield of usable samples. Here, we screen 10 graphene-on-glass preparation methods and present an optimized protocol. To obtain the required quality for single-molecule and super-resolution imaging on graphene, we introduce a graphene screening method that avoids consuming the investigated sample. We apply DNA origami nanostructures to place fluorescent probes at a defined distance on top of graphene-on-glass coverslips. Subsequent fluorescence lifetime imaging directly reports on the graphene quality, as deviations from the expected fluorescence lifetime indicate imperfections. We compare the DNA origami probes with conventional techniques for graphene characterization, including light microscopy, atomic force microscopy, and Raman spectroscopy. For the latter, we observe a discrepancy between the graphene quality implied by Raman spectra in comparison to the quality probed by fluorescence lifetime quenching measured at the same position. We attribute this discrepancy to the difference in the effective area that is probed by Raman spectroscopy and fluorescence quenching. Moreover, we demonstrate the applicability of already screened and positively evaluated graphene for studying single-molecule conformational dynamics on a second DNA origami structure. Our results constitute the basis for graphene-based biophysics and super-resolution microscopy.}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close Graphene exhibits outstanding fluorescence quenching properties that can become useful for biophysics and biosensing applications, but it remains challenging to harness these advantages due to the complex transfer procedure of chemical vapor deposition-grown graphene to glass coverslips and the low yield of usable samples. Here, we screen 10 graphene-on-glass preparation methods and present an optimized protocol. To obtain the required quality for single-molecule and super-resolution imaging on graphene, we introduce a graphene screening method that avoids consuming the investigated sample. We apply DNA origami nanostructures to place fluorescent probes at a defined distance on top of graphene-on-glass coverslips. Subsequent fluorescence lifetime imaging directly reports on the graphene quality, as deviations from the expected fluorescence lifetime indicate imperfections. We compare the DNA origami probes with conventional techniques for graphene characterization, including light microscopy, atomic force microscopy, and Raman spectroscopy. For the latter, we observe a discrepancy between the graphene quality implied by Raman spectra in comparison to the quality probed by fluorescence lifetime quenching measured at the same position. We attribute this discrepancy to the difference in the effective area that is probed by Raman spectroscopy and fluorescence quenching. Moreover, we demonstrate the applicability of already screened and positively evaluated graphene for studying single-molecule conformational dynamics on a second DNA origami structure. Our results constitute the basis for graphene-based biophysics and super-resolution microscopy. Close https://pubs.acs.org/doi/abs/10.1021/acsnano.0c08383 doi:10.1021/acsnano.0c08383 Close
228.	C Griesser, H Li, E-M Wernig, D Winkler, Shakibi N Nia, T Mairegger, T Götsch, T Schachinger, A Steiger-Thirsfeld, S Penner, D Wielend, D Egger, C Scheurer, K Reuter, J Kunze-Liebhäuser True Nature of the Transition-Metal Carbide/Liquid Interface Determines Its Reactivity Journal Article ACS Catalysis, pp. 4920-4928, 2021. Abstract \| Links \| Tags: Solid-Liquid @article{, title = {True Nature of the Transition-Metal Carbide/Liquid Interface Determines Its Reactivity}, author = {C Griesser and H Li and E-M Wernig and D Winkler and Shakibi N Nia and T Mairegger and T G\"{o}tsch and T Schachinger and A Steiger-Thirsfeld and S Penner and D Wielend and D Egger and C Scheurer and K Reuter and J Kunze-Liebh\"{a}user}, url = {https://pubs.acs.org/doi/abs/10.1021/acscatal.1c00415}, doi = {10.1021/acscatal.1c00415}, year = {2021}, date = {2021-04-07}, journal = {ACS Catalysis}, pages = {4920-4928}, abstract = {Compound materials, such as transition-metal (TM) carbides, are anticipated to be effective electrocatalysts for the carbon dioxide reduction reaction (CO2RR) to useful chemicals. This expectation is nurtured by density functional theory (DFT) predictions of a break of key adsorption energy scaling relations that limit CO2RR at parent TMs. Here, we evaluate these prospects for hexagonal Mo2C in aqueous electrolytes in a multimethod experiment and theory approach. We find that surface oxide formation completely suppresses the CO2 activation. The oxides are stable down to potentials as low as −1.9 V versus the standard hydrogen electrode, and solely the hydrogen evolution reaction (HER) is found to be active. This generally points to the absolute imperative of recognizing the true interface establishing under operando conditions in computational screening of catalyst materials. When protected from ambient air and used in nonaqueous electrolyte, Mo2C indeed shows CO2RR activity.}, keywords = {Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Compound materials, such as transition-metal (TM) carbides, are anticipated to be effective electrocatalysts for the carbon dioxide reduction reaction (CO2RR) to useful chemicals. This expectation is nurtured by density functional theory (DFT) predictions of a break of key adsorption energy scaling relations that limit CO2RR at parent TMs. Here, we evaluate these prospects for hexagonal Mo2C in aqueous electrolytes in a multimethod experiment and theory approach. We find that surface oxide formation completely suppresses the CO2 activation. The oxides are stable down to potentials as low as −1.9 V versus the standard hydrogen electrode, and solely the hydrogen evolution reaction (HER) is found to be active. This generally points to the absolute imperative of recognizing the true interface establishing under operando conditions in computational screening of catalyst materials. When protected from ambient air and used in nonaqueous electrolyte, Mo2C indeed shows CO2RR activity. Close https://pubs.acs.org/doi/abs/10.1021/acscatal.1c00415 doi:10.1021/acscatal.1c00415 Close
227.	L Sortino, P G Zotev, C L Phillips, A J Brash, J Cambiasso, E Marensi, A M Fox, S A Maier, R Sapienza, A I Tartakovskii Bright single photon emitters with enhanced quantum efficiency in a two-dimensional semiconductor coupled with dielectric nano-antennas Journal Article arXiv preprint arXiv:2103.16986, 2021. Tags: Solid-Solid @article{, title = {Bright single photon emitters with enhanced quantum efficiency in a two-dimensional semiconductor coupled with dielectric nano-antennas}, author = {L Sortino and P G Zotev and C L Phillips and A J Brash and J Cambiasso and E Marensi and A M Fox and S A Maier and R Sapienza and A I Tartakovskii}, year = {2021}, date = {2021-04-05}, journal = {arXiv preprint arXiv:2103.16986}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close
226.	R W Haid, R M Kluge, T O Schmidt, A S Bandarenka In-situ Detection of Active Sites for Carbon-Based Bifunctional Oxygen Reduction and Evolution Catalysis Journal Article Electrochimica Acta, pp. 138285, 2021, ISSN: 0013-4686. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {In-situ Detection of Active Sites for Carbon-Based Bifunctional Oxygen Reduction and Evolution Catalysis}, author = {R W Haid and R M Kluge and T O Schmidt and A S Bandarenka}, url = {https://www.sciencedirect.com/science/article/pii/S0013468621005752}, doi = {https://doi.org/10.1016/j.electacta.2021.138285}, issn = {0013-4686}, year = {2021}, date = {2021-04-02}, journal = {Electrochimica Acta}, pages = {138285}, abstract = {Due to their availability and electrochemical versatility, carbon-based electrodes are becoming an increasingly popular option as electrocatalysts for fuel cells and metal-air batteries. Additionally, they show great potential as bifunctional catalysts for the oxygen reduction and evolution reaction (ORR/OER) in an alkaline medium. However, to compete with state-of-the-art catalysts, the nature of the active sites and the surface stability under reaction conditions need to be understood in depth. Here, we present a principle study on highly oriented pyrolytic graphite (HOPG), evaluating the surface behavior under both ORR and OER conditions in 0.1 M KOH. We use noise analysis in electrochemical scanning tunneling microscopy (n-EC-STM) to monitor and compare ORR and OER active sites with resolution down to the nanoscale. Furthermore, surface degradation can be evaluated during the operation. We find that close to the respective reaction onset, step sites and defects are active for both ORR and OER. Terraces sites are largely inactive and only become involved in the OER at higher potentials. This could imply corrosion of the carbon. However, since the observed surface structures remain unaltered before and after applying the OER in our experiments, we find no clear evidence of surface destruction. These fundamental insights could inspire further research concerning the active sites and stability of carbon-based catalysts as well as carbon support structures, to discover ways to tune the surface activity and stability to the dedicated purpose.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Due to their availability and electrochemical versatility, carbon-based electrodes are becoming an increasingly popular option as electrocatalysts for fuel cells and metal-air batteries. Additionally, they show great potential as bifunctional catalysts for the oxygen reduction and evolution reaction (ORR/OER) in an alkaline medium. However, to compete with state-of-the-art catalysts, the nature of the active sites and the surface stability under reaction conditions need to be understood in depth. Here, we present a principle study on highly oriented pyrolytic graphite (HOPG), evaluating the surface behavior under both ORR and OER conditions in 0.1 M KOH. We use noise analysis in electrochemical scanning tunneling microscopy (n-EC-STM) to monitor and compare ORR and OER active sites with resolution down to the nanoscale. Furthermore, surface degradation can be evaluated during the operation. We find that close to the respective reaction onset, step sites and defects are active for both ORR and OER. Terraces sites are largely inactive and only become involved in the OER at higher potentials. This could imply corrosion of the carbon. However, since the observed surface structures remain unaltered before and after applying the OER in our experiments, we find no clear evidence of surface destruction. These fundamental insights could inspire further research concerning the active sites and stability of carbon-based catalysts as well as carbon support structures, to discover ways to tune the surface activity and stability to the dedicated purpose. Close https://www.sciencedirect.com/science/article/pii/S0013468621005752 doi:https://doi.org/10.1016/j.electacta.2021.138285 Close
225.	H Li, K Liu, J Fu, K Chen, K Yang, Y Lin, B Yang, Q Wang, H Pan, Z Cai, H Li, M Cao, J Hu, Y-R Lu, T-S Chan, E Cortés, A Fratalocchi, M Liu Paired Ru‒O‒Mo ensemble for efficient and stable alkaline hydrogen evolution reaction Journal Article Nano Energy, 82 , pp. 105767, 2021, ISSN: 2211-2855. Abstract \| Links \| Tags: Solid-Liquid @article{, title = {Paired Ru‒O‒Mo ensemble for efficient and stable alkaline hydrogen evolution reaction}, author = {H Li and K Liu and J Fu and K Chen and K Yang and Y Lin and B Yang and Q Wang and H Pan and Z Cai and H Li and M Cao and J Hu and Y-R Lu and T-S Chan and E Cort\'{e}s and A Fratalocchi and M Liu}, url = {http://www.sciencedirect.com/science/article/pii/S2211285521000252}, doi = {https://doi.org/10.1016/j.nanoen.2021.105767}, issn = {2211-2855}, year = {2021}, date = {2021-04-01}, journal = {Nano Energy}, volume = {82}, pages = {105767}, abstract = {Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is a promising electrochemical energy conversion strategy. Ruthenium (Ru) is an efficient catalyst with a desirable cost for HER, however, the sluggish H2O dissociation process, due to the low H2O adsorption on its surface, currently hampers the performances of this catalyst in alkaline HER. Herein, we demonstrate that the H2O adsorption improves significantly by the construction of Ru\textendashO\textendashMo sites. We prepared Ru/MoO2 catalysts with Ru\textendashO\textendashMo sites through a facile thermal treatment process and assessed the creation of Ru\textendashO\textendashMo interfaces by transmission electron microscope (TEM) and extended X-ray absorption fine structure (EXAFS). By using Fourier-transform infrared spectroscopy (FTIR) and H2O adsorption tests, we proved Ru\textendashO\textendashMo sites have tenfold stronger H2O adsorption ability than that of Ru catalyst. The catalysts with Ru\textendashO\textendashMo sites exhibited a state-of-the-art overpotential of 16 mV at 10 mA cm\textendash2 in 1 M KOH electrolyte, demonstrating a threefold reduction than the previous bests of Ru (59 mV) and commercial Pt (31 mV) catalysts. We proved the stability of these performances over 40 h without decline. These results could open a new path for designing efficient and stable catalysts.}, keywords = {Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is a promising electrochemical energy conversion strategy. Ruthenium (Ru) is an efficient catalyst with a desirable cost for HER, however, the sluggish H2O dissociation process, due to the low H2O adsorption on its surface, currently hampers the performances of this catalyst in alkaline HER. Herein, we demonstrate that the H2O adsorption improves significantly by the construction of Ru–O–Mo sites. We prepared Ru/MoO2 catalysts with Ru–O–Mo sites through a facile thermal treatment process and assessed the creation of Ru–O–Mo interfaces by transmission electron microscope (TEM) and extended X-ray absorption fine structure (EXAFS). By using Fourier-transform infrared spectroscopy (FTIR) and H2O adsorption tests, we proved Ru–O–Mo sites have tenfold stronger H2O adsorption ability than that of Ru catalyst. The catalysts with Ru–O–Mo sites exhibited a state-of-the-art overpotential of 16 mV at 10 mA cm–2 in 1 M KOH electrolyte, demonstrating a threefold reduction than the previous bests of Ru (59 mV) and commercial Pt (31 mV) catalysts. We proved the stability of these performances over 40 h without decline. These results could open a new path for designing efficient and stable catalysts. Close http://www.sciencedirect.com/science/article/pii/S2211285521000252 doi:https://doi.org/10.1016/j.nanoen.2021.105767 Close
224.	W Li, S Mukerjee, B Ren, R Cao, R A Fischer Open Framework Material Based Thin Films: Electrochemical Catalysis and State-of-the-art Technologies Journal Article Advanced Energy Materials, n/a (n/a), pp. 2003499, 2021, ISSN: 1614-6832. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Open Framework Material Based Thin Films: Electrochemical Catalysis and State-of-the-art Technologies}, author = {W Li and S Mukerjee and B Ren and R Cao and R A Fischer}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202003499}, doi = {https://doi.org/10.1002/aenm.202003499}, issn = {1614-6832}, year = {2021}, date = {2021-04-01}, journal = {Advanced Energy Materials}, volume = {n/a}, number = {n/a}, pages = {2003499}, abstract = {Abstract Open framework materials (OFMs), such as metal-organic frameworks and covalent organic frameworks have emerged as promising electrocatalysts to address the global energy crisis and environmental problems. Powdered non-film forms, that is, bulk OFMs exhibit excellent catalytic activities toward electrocatalytic carbon dioxide reduction, water splitting, and the oxygen reduction reaction. However, electrode preparation using bulk solids suffers from a range of oft-encountered difficulties, primarily limited by challenges in controlling their thickness, roughness, and particle sizes, despite early performance promises. Targeting energy sustainability, it is a matter of growing interest to directly integrate OFMs in the form of thin films onto conductive substrates. In essence, this leads to electrocatalysts with controlled features: thickness, roughness, and particle sizes. Thus far, there are only a handful of OFM thin films developed for electrocatalysis. Exploration of these understudied OFM thin films to serve electrocatalysis still lies at its infancy. This review will cover the key discoveries of OFM thin films as electrocatalysts and will critically examine the strengths, challenges, and future goals in exploring bespoke OFM thin films for electrocatalysis, under conditions that mimic real-world applications.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Abstract Open framework materials (OFMs), such as metal-organic frameworks and covalent organic frameworks have emerged as promising electrocatalysts to address the global energy crisis and environmental problems. Powdered non-film forms, that is, bulk OFMs exhibit excellent catalytic activities toward electrocatalytic carbon dioxide reduction, water splitting, and the oxygen reduction reaction. However, electrode preparation using bulk solids suffers from a range of oft-encountered difficulties, primarily limited by challenges in controlling their thickness, roughness, and particle sizes, despite early performance promises. Targeting energy sustainability, it is a matter of growing interest to directly integrate OFMs in the form of thin films onto conductive substrates. In essence, this leads to electrocatalysts with controlled features: thickness, roughness, and particle sizes. Thus far, there are only a handful of OFM thin films developed for electrocatalysis. Exploration of these understudied OFM thin films to serve electrocatalysis still lies at its infancy. This review will cover the key discoveries of OFM thin films as electrocatalysts and will critically examine the strengths, challenges, and future goals in exploring bespoke OFM thin films for electrocatalysis, under conditions that mimic real-world applications. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202003499 doi:https://doi.org/10.1002/aenm.202003499 Close
223.	S Kaiser, F Maleki, K Zhang, W Harbich, U Heiz, S Tosoni, B A Lechner, G Pacchioni, F Esch Cluster Catalysis with Lattice Oxygen: Tracing Oxygen Transport from a Magnetite (001) Support onto Small Pt Clusters Journal Article arXiv preprint arXiv:2103.16413, 2021. Tags: Solid-Solid @article{, title = {Cluster Catalysis with Lattice Oxygen: Tracing Oxygen Transport from a Magnetite (001) Support onto Small Pt Clusters}, author = {S Kaiser and F Maleki and K Zhang and W Harbich and U Heiz and S Tosoni and B A Lechner and G Pacchioni and F Esch}, year = {2021}, date = {2021-03-30}, journal = {arXiv preprint arXiv:2103.16413}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close
222.	A Mähringer, M Döblinger, M Hennemann, C Gruber, D Fehn, P I Scheurle, P Hosseini, I Santourian, A Schirmacher, J M Rotter, G Wittstock, K Meyer, T Clark, T Bein, D D Medina An electrically conducting three-dimensional iron-catecholate porous framework Journal Article Angewandte Chemie International Edition, n/a (n/a), 2021, ISSN: 1433-7851. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {An electrically conducting three-dimensional iron-catecholate porous framework}, author = {A M\"{a}hringer and M D\"{o}blinger and M Hennemann and C Gruber and D Fehn and P I Scheurle and P Hosseini and I Santourian and A Schirmacher and J M Rotter and G Wittstock and K Meyer and T Clark and T Bein and D D Medina}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202102670}, doi = {https://doi.org/10.1002/anie.202102670}, issn = {1433-7851}, year = {2021}, date = {2021-03-29}, journal = {Angewandte Chemie International Edition}, volume = {n/a}, number = {n/a}, abstract = {Here, we report the synthesis of a unique cubic metal-organic framework (MOF), the Fe-HHTP-MOF, comprising hexahydroxytriphenylene (HHTP) supertetrahedral units and FeIII ions, arranged in a diamond topology. The MOF is synthesized under solvothermal conditions, yielding a highly crystalline, deep black powder, with crystallites of 300-500 nm size and tetrahedral morphology. Nitrogen sorption analysis indicates a highly porous material with a surface area exceeding 1400 m2 g−1. Furthermore, Fe-HHTP-MOF shows broadband absorption from 475 nm up to 1900 nm with excellent absorption capability of 98.5% of the incoming light over the visible spectral region. Electrical conductivity measurements of pressed pellets reveal a high intrinsic electrical conductivity of up to 10−3 S cm−1. Quantum mechanical calculations predict Fe-HHTP-MOF to be an efficient electron conductor, exhibiting continuous charge-carrier pathways throughout the structure. This report expands the paradigm of intrinsically electroactive MOFs, serving as a solid basis for the development of highly porous, ordered frameworks with enhanced electrical conductivity.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Here, we report the synthesis of a unique cubic metal-organic framework (MOF), the Fe-HHTP-MOF, comprising hexahydroxytriphenylene (HHTP) supertetrahedral units and FeIII ions, arranged in a diamond topology. The MOF is synthesized under solvothermal conditions, yielding a highly crystalline, deep black powder, with crystallites of 300-500 nm size and tetrahedral morphology. Nitrogen sorption analysis indicates a highly porous material with a surface area exceeding 1400 m2 g−1. Furthermore, Fe-HHTP-MOF shows broadband absorption from 475 nm up to 1900 nm with excellent absorption capability of 98.5% of the incoming light over the visible spectral region. Electrical conductivity measurements of pressed pellets reveal a high intrinsic electrical conductivity of up to 10−3 S cm−1. Quantum mechanical calculations predict Fe-HHTP-MOF to be an efficient electron conductor, exhibiting continuous charge-carrier pathways throughout the structure. This report expands the paradigm of intrinsically electroactive MOFs, serving as a solid basis for the development of highly porous, ordered frameworks with enhanced electrical conductivity. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202102670 doi:https://doi.org/10.1002/anie.202102670 Close
221.	F Devaux, X Li, D Sluysmans, V Maurizot, E Bakalis, F Zerbetto, I Huc, A-S Duwez Single-molecule mechanics of synthetic aromatic amide helices: Ultrafast and robust non-dissipative winding Journal Article Chem, 2021, ISSN: 2451-9294. Tags: Foundry Organic @article{, title = {Single-molecule mechanics of synthetic aromatic amide helices: Ultrafast and robust non-dissipative winding}, author = {F Devaux and X Li and D Sluysmans and V Maurizot and E Bakalis and F Zerbetto and I Huc and A-S Duwez}, issn = {2451-9294}, year = {2021}, date = {2021-03-26}, journal = {Chem}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close
220.	R Kluge, R W Haid, I Stephens, F Calle-Vallejo, A Bandarenka Monitoring Active Sites for Hydrogen Evolution Reaction at Model Carbon Surfaces Journal Article Physical Chemistry Chemical Physics, 2021, ISSN: 1463-9076. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Solid @article{, title = {Monitoring Active Sites for Hydrogen Evolution Reaction at Model Carbon Surfaces}, author = {R Kluge and R W Haid and I Stephens and F Calle-Vallejo and A Bandarenka}, url = {http://dx.doi.org/10.1039/D1CP00434D}, doi = {10.1039/D1CP00434D}, issn = {1463-9076}, year = {2021}, date = {2021-03-25}, journal = {Physical Chemistry Chemical Physics}, abstract = {Carbon is ubiquitous as an electrode material in electrochemical energy conversion devices. If used as support material, the evolution of H2 is undesired on carbon. However, recently carbon-based materials are of high interest as economic and eco-conscious alternative to noble metal catalysts. The targeted design of improved carbon electrode materials requires atomic scale insight into the structure of the sites that catalyse H2 evolution. This work demonstrates that electrochemical scanning tunnelling microscopy under reaction conditions (n-EC-STM) can monitor active sites of highly oriented pyrolytic graphite for the hydrogen evolution reaction. With down to atomic resolution, the most active sites in acidic medium are pinpointed near edge sites and defects, whereas the basal planes remain inactive. Density functional theory calculations support these findings and reveal that only specific defects on graphite are active. Motivated by these results, the extensive usage of n-EC-STM on doped carbon-based materials is encouraged to locate their active sites and guide the synthesis of enhanced electrocatalysts.}, keywords = {Foundry Inorganic, Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Carbon is ubiquitous as an electrode material in electrochemical energy conversion devices. If used as support material, the evolution of H2 is undesired on carbon. However, recently carbon-based materials are of high interest as economic and eco-conscious alternative to noble metal catalysts. The targeted design of improved carbon electrode materials requires atomic scale insight into the structure of the sites that catalyse H2 evolution. This work demonstrates that electrochemical scanning tunnelling microscopy under reaction conditions (n-EC-STM) can monitor active sites of highly oriented pyrolytic graphite for the hydrogen evolution reaction. With down to atomic resolution, the most active sites in acidic medium are pinpointed near edge sites and defects, whereas the basal planes remain inactive. Density functional theory calculations support these findings and reveal that only specific defects on graphite are active. Motivated by these results, the extensive usage of n-EC-STM on doped carbon-based materials is encouraged to locate their active sites and guide the synthesis of enhanced electrocatalysts. Close http://dx.doi.org/10.1039/D1CP00434D doi:10.1039/D1CP00434D Close
219.	D Bessinger, K Muggli, M Beetz, F Auras, T Bein Fast-Switching Vis–IR Electrochromic Covalent Organic Frameworks Journal Article Journal of the American Chemical Society, 2021, ISSN: 0002-7863. Abstract \| Links \| Tags: Foundry Organic, Molecularly-Functionalized @article{, title = {Fast-Switching Vis\textendashIR Electrochromic Covalent Organic Frameworks}, author = {D Bessinger and K Muggli and M Beetz and F Auras and T Bein}, url = {https://doi.org/10.1021/jacs.0c12392}, doi = {10.1021/jacs.0c12392}, issn = {0002-7863}, year = {2021}, date = {2021-03-16}, journal = {Journal of the American Chemical Society}, abstract = {Electrochromic coatings are promising for applications in smart windows or energy-efficient optical displays. However, classical inorganic electrochromic materials such as WO3 suffer from low coloration efficiency and slow switching speed. We have developed highly efficient and fast-switching electrochromic thin films based on fully organic, porous covalent organic frameworks (COFs). The low band gap COFs have strong vis\textendashNIR absorption bands in the neutral state, which shift significantly upon electrochemical oxidation. Fully reversible absorption changes by close to 3 OD can be triggered at low operating voltages and low charge per unit area. Our champion material reaches an electrochromic coloration efficiency of 858 cm2 C\textendash1 at 880 nm and retains >95% of its electrochromic response over 100 oxidation/reduction cycles. Furthermore, the electrochromic switching is extremely fast with response times below 0.4 s for the oxidation and around 0.2 s for the reduction, outperforming previous COFs by at least an order of magnitude and rendering these materials some of the fastest-switching frameworks to date. This combination of high coloration efficiency and very fast switching reveals intriguing opportunities for applications of porous organic electrochromic materials.}, keywords = {Foundry Organic, Molecularly-Functionalized}, pubstate = {published}, tppubtype = {article} } Close Electrochromic coatings are promising for applications in smart windows or energy-efficient optical displays. However, classical inorganic electrochromic materials such as WO3 suffer from low coloration efficiency and slow switching speed. We have developed highly efficient and fast-switching electrochromic thin films based on fully organic, porous covalent organic frameworks (COFs). The low band gap COFs have strong vis–NIR absorption bands in the neutral state, which shift significantly upon electrochemical oxidation. Fully reversible absorption changes by close to 3 OD can be triggered at low operating voltages and low charge per unit area. Our champion material reaches an electrochromic coloration efficiency of 858 cm2 C–1 at 880 nm and retains >95% of its electrochromic response over 100 oxidation/reduction cycles. Furthermore, the electrochromic switching is extremely fast with response times below 0.4 s for the oxidation and around 0.2 s for the reduction, outperforming previous COFs by at least an order of magnitude and rendering these materials some of the fastest-switching frameworks to date. This combination of high coloration efficiency and very fast switching reveals intriguing opportunities for applications of porous organic electrochromic materials. Close https://doi.org/10.1021/jacs.0c12392 doi:10.1021/jacs.0c12392 Close
218.	J P Sabawa, A S Bandarenka Investigation of degradation mechanisms in PEM fuel cells caused by low-temperature cycles Journal Article International Journal of Hydrogen Energy, 2021, ISSN: 0360-3199. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Investigation of degradation mechanisms in PEM fuel cells caused by low-temperature cycles}, author = {J P Sabawa and A S Bandarenka}, url = {https://www.sciencedirect.com/science/article/pii/S0360319921005917}, doi = {https://doi.org/10.1016/j.ijhydene.2021.02.088}, issn = {0360-3199}, year = {2021}, date = {2021-03-05}, journal = {International Journal of Hydrogen Energy}, abstract = {Environmental influences, especially temperatures below the freezing point, can affect the performance and long-term stability of PEMFCs. Within the scope of this research, a completely new test procedure was developed to characterize PEMFC single cells with respect to their long-term stability at temperature cycles between 80 °C and −10 °C. Using this procedure, the behavior of PEMFC single cells (active surface area of 43.6 cm2) with different cathode-ionomer-to-carbon (I/C) weight ratios (0.5/1.0/1.5) was evaluated. The generated in-situ measurement data clearly demonstrate that the performance of each PEMFC single cell changes individually as a function of the cathode I/C-ratio during the 120 stress cycles. While the MEA with an I/C ratio of 0.5 showed a power loss of ~1.49%, the MEAs with an I/C ratio of 1.0 and 1.5 showed a power loss of about ~7.75% and ~24.7%, respectively. The subsequent post-mortem ex-situ analyses clearly showed how the test procedure and the different I/C-ratios affected the changes in the catalyst layers (CL). The destructive mechanisms responsible for the changes can be divided into two categories: One part was driven by rapid enthalpy change leading to mechanical failure, and the other part, which led to the reduction of cathode CL thickness, was driven by rapid potential changes and potential shifts (overpotentials). This reduction in cathode CL thickness ultimately leads to an accumulation and excessive load of ionomer in the direction of GDL, resulting in a reduction in pore size, a shift in the core reaction area, and high O2 transport resistance.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Environmental influences, especially temperatures below the freezing point, can affect the performance and long-term stability of PEMFCs. Within the scope of this research, a completely new test procedure was developed to characterize PEMFC single cells with respect to their long-term stability at temperature cycles between 80 °C and −10 °C. Using this procedure, the behavior of PEMFC single cells (active surface area of 43.6 cm2) with different cathode-ionomer-to-carbon (I/C) weight ratios (0.5/1.0/1.5) was evaluated. The generated in-situ measurement data clearly demonstrate that the performance of each PEMFC single cell changes individually as a function of the cathode I/C-ratio during the 120 stress cycles. While the MEA with an I/C ratio of 0.5 showed a power loss of ~1.49%, the MEAs with an I/C ratio of 1.0 and 1.5 showed a power loss of about ~7.75% and ~24.7%, respectively. The subsequent post-mortem ex-situ analyses clearly showed how the test procedure and the different I/C-ratios affected the changes in the catalyst layers (CL). The destructive mechanisms responsible for the changes can be divided into two categories: One part was driven by rapid enthalpy change leading to mechanical failure, and the other part, which led to the reduction of cathode CL thickness, was driven by rapid potential changes and potential shifts (overpotentials). This reduction in cathode CL thickness ultimately leads to an accumulation and excessive load of ionomer in the direction of GDL, resulting in a reduction in pore size, a shift in the core reaction area, and high O2 transport resistance. Close https://www.sciencedirect.com/science/article/pii/S0360319921005917 doi:https://doi.org/10.1016/j.ijhydene.2021.02.088 Close
217.	K Hübner, H Joshi, A Aksimentiev, F D Stefani, P Tinnefeld, G P Acuna Determining the In-Plane Orientation and Binding Mode of Single Fluorescent Dyes in DNA Origami Structures Journal Article ACS Nano, 2021, ISSN: 1936-0851. Abstract \| Links \| Tags: Foundry Organic @article{, title = {Determining the In-Plane Orientation and Binding Mode of Single Fluorescent Dyes in DNA Origami Structures}, author = {K H\"{u}bner and H Joshi and A Aksimentiev and F D Stefani and P Tinnefeld and G P Acuna}, url = {https://doi.org/10.1021/acsnano.0c10259}, doi = {10.1021/acsnano.0c10259}, issn = {1936-0851}, year = {2021}, date = {2021-03-04}, journal = {ACS Nano}, abstract = {We present a technique to determine the orientation of single fluorophores attached to DNA origami structures based on two measurements. First, the orientation of the absorption transition dipole of the molecule is determined through a polarization-resolved excitation measurement. Second, the orientation of the DNA origami structure is obtained from a DNA-PAINT nanoscopy measurement. Both measurements are performed consecutively on a fluorescence wide-field microscope. We employed this approach to study the orientation of single ATTO 647N, ATTO 643, and Cy5 fluorophores covalently attached to a 2D rectangular DNA origami structure with different nanoenvironments, achieved by changing both the fluorophores’ binding position and immediate vicinity. Our results show that when fluorophores are incorporated with additional space, for example, by omitting nucleotides in an elsewise double-stranded environment, they tend to stick to the DNA and to adopt a preferred orientation that depends more on the specific molecular environment than on the fluorophore type. With the aid of all-atom molecular dynamics simulations, we rationalized our observations and provide insight into the fluorophores’ probable binding modes. We believe this work constitutes an important step toward manipulating the orientation of single fluorophores in DNA origami structures, which is vital for the development of more efficient and reproducible self-assembled nanophotonic devices.}, keywords = {Foundry Organic}, pubstate = {published}, tppubtype = {article} } Close We present a technique to determine the orientation of single fluorophores attached to DNA origami structures based on two measurements. First, the orientation of the absorption transition dipole of the molecule is determined through a polarization-resolved excitation measurement. Second, the orientation of the DNA origami structure is obtained from a DNA-PAINT nanoscopy measurement. Both measurements are performed consecutively on a fluorescence wide-field microscope. We employed this approach to study the orientation of single ATTO 647N, ATTO 643, and Cy5 fluorophores covalently attached to a 2D rectangular DNA origami structure with different nanoenvironments, achieved by changing both the fluorophores’ binding position and immediate vicinity. Our results show that when fluorophores are incorporated with additional space, for example, by omitting nucleotides in an elsewise double-stranded environment, they tend to stick to the DNA and to adopt a preferred orientation that depends more on the specific molecular environment than on the fluorophore type. With the aid of all-atom molecular dynamics simulations, we rationalized our observations and provide insight into the fluorophores’ probable binding modes. We believe this work constitutes an important step toward manipulating the orientation of single fluorophores in DNA origami structures, which is vital for the development of more efficient and reproducible self-assembled nanophotonic devices. Close https://doi.org/10.1021/acsnano.0c10259 doi:10.1021/acsnano.0c10259 Close
216.	A Auer, X Ding, A S Bandarenka, J Kunze-Liebhäuser The Potential of Zero Charge and the Electrochemical Interface Structure of Cu(111) in Alkaline Solutions Journal Article The Journal of Physical Chemistry C, 2021, ISSN: 1932-7447. Abstract \| Links \| Tags: Foundry Inorganic, Solid-Liquid @article{, title = {The Potential of Zero Charge and the Electrochemical Interface Structure of Cu(111) in Alkaline Solutions}, author = {A Auer and X Ding and A S Bandarenka and J Kunze-Liebh\"{a}user}, url = {https://doi.org/10.1021/acs.jpcc.0c09289}, doi = {10.1021/acs.jpcc.0c09289}, issn = {1932-7447}, year = {2021}, date = {2021-03-01}, journal = {The Journal of Physical Chemistry C}, abstract = {Copper (Cu) is a unique electrocatalyst, which is able to efficiently oxidize CO at very low overpotentials and reduce CO2 to valuable fuels with reasonable Faradaic efficiencies. Yet, knowledge of its electrochemical properties at the solid/liquid interface is still scarce. Here, we present the first two-stranded correlation of the potential of zero free charge (pzfc) of Cu(111) in alkaline electrolyte at different pH values through application of nanosecond laser pulses and the corresponding interfacial structure changes by in situ electrochemical scanning tunneling microscopy imaging. The pzfc of Cu(111) at pH 13 is identified at −0.73 VSHE in the apparent double layer region, prior to the onset of hydroxide adsorption. It shifts by (88 ± 4) mV to more positive potentials per decreasing pH unit. At the pzfc, Cu(111) shows structural dynamics at both pH 13 and pH 11, which can be understood as the onset of surface restructuring. At higher potentials, full reconstruction and electric field dependent OH adsorption occurs, which causes a remarkable decrease in the atomic density of the first Cu layer. The expansion of the Cu\textendashCu distance to 0.3 nm generates a hexagonal Moir\'{e} pattern, on which the adsorbed OH forms a commensurate (1 × 2) adlayer structure with a steady state coverage of 0.5 monolayers at pH 13. Our experimental findings shed light on the true charge distribution and its interrelation with the atomic structure of the electrochemical interface of Cu.}, keywords = {Foundry Inorganic, Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Copper (Cu) is a unique electrocatalyst, which is able to efficiently oxidize CO at very low overpotentials and reduce CO2 to valuable fuels with reasonable Faradaic efficiencies. Yet, knowledge of its electrochemical properties at the solid/liquid interface is still scarce. Here, we present the first two-stranded correlation of the potential of zero free charge (pzfc) of Cu(111) in alkaline electrolyte at different pH values through application of nanosecond laser pulses and the corresponding interfacial structure changes by in situ electrochemical scanning tunneling microscopy imaging. The pzfc of Cu(111) at pH 13 is identified at −0.73 VSHE in the apparent double layer region, prior to the onset of hydroxide adsorption. It shifts by (88 ± 4) mV to more positive potentials per decreasing pH unit. At the pzfc, Cu(111) shows structural dynamics at both pH 13 and pH 11, which can be understood as the onset of surface restructuring. At higher potentials, full reconstruction and electric field dependent OH adsorption occurs, which causes a remarkable decrease in the atomic density of the first Cu layer. The expansion of the Cu–Cu distance to 0.3 nm generates a hexagonal Moiré pattern, on which the adsorbed OH forms a commensurate (1 × 2) adlayer structure with a steady state coverage of 0.5 monolayers at pH 13. Our experimental findings shed light on the true charge distribution and its interrelation with the atomic structure of the electrochemical interface of Cu. Close https://doi.org/10.1021/acs.jpcc.0c09289 doi:10.1021/acs.jpcc.0c09289 Close
215.	G J Hedley, T Schröder, F Steiner, T Eder, F J Hofmann, S Bange, D Laux, S Höger, P Tinnefeld, J M Lupton, J Vogelsang Picosecond time-resolved photon antibunching measures nanoscale exciton motion and the true number of chromophores Journal Article Nature Communications, 12 (1), pp. 1327, 2021, ISSN: 2041-1723. Abstract \| Links \| Tags: Foundry Organic, Molecularly-Functionalized @article{, title = {Picosecond time-resolved photon antibunching measures nanoscale exciton motion and the true number of chromophores}, author = {G J Hedley and T Schr\"{o}der and F Steiner and T Eder and F J Hofmann and S Bange and D Laux and S H\"{o}ger and P Tinnefeld and J M Lupton and J Vogelsang}, url = {https://doi.org/10.1038/s41467-021-21474-z}, doi = {10.1038/s41467-021-21474-z}, issn = {2041-1723}, year = {2021}, date = {2021-02-26}, journal = {Nature Communications}, volume = {12}, number = {1}, pages = {1327}, abstract = {The particle-like nature of light becomes evident in the photon statistics of fluorescence from single quantum systems as photon antibunching. In multichromophoric systems, exciton diffusion and subsequent annihilation occurs. These processes also yield photon antibunching but cannot be interpreted reliably. Here we develop picosecond time-resolved antibunching to identify and decode such processes. We use this method to measure the true number of chromophores on well-defined multichromophoric DNA-origami structures, and precisely determine the distance-dependent rates of annihilation between excitons. Further, this allows us to measure exciton diffusion in mesoscopic H- and J-type conjugated-polymer aggregates. We distinguish between one-dimensional intra-chain and three-dimensional inter-chain exciton diffusion at different times after excitation and determine the disorder-dependent diffusion lengths. Our method provides a powerful lens through which excitons can be studied at the single-particle level, enabling the rational design of improved excitonic probes such as ultra-bright fluorescent nanoparticles and materials for optoelectronic devices.}, keywords = {Foundry Organic, Molecularly-Functionalized}, pubstate = {published}, tppubtype = {article} } Close The particle-like nature of light becomes evident in the photon statistics of fluorescence from single quantum systems as photon antibunching. In multichromophoric systems, exciton diffusion and subsequent annihilation occurs. These processes also yield photon antibunching but cannot be interpreted reliably. Here we develop picosecond time-resolved antibunching to identify and decode such processes. We use this method to measure the true number of chromophores on well-defined multichromophoric DNA-origami structures, and precisely determine the distance-dependent rates of annihilation between excitons. Further, this allows us to measure exciton diffusion in mesoscopic H- and J-type conjugated-polymer aggregates. We distinguish between one-dimensional intra-chain and three-dimensional inter-chain exciton diffusion at different times after excitation and determine the disorder-dependent diffusion lengths. Our method provides a powerful lens through which excitons can be studied at the single-particle level, enabling the rational design of improved excitonic probes such as ultra-bright fluorescent nanoparticles and materials for optoelectronic devices. Close https://doi.org/10.1038/s41467-021-21474-z doi:10.1038/s41467-021-21474-z Close
214.	A M Molszalai, B Siarry, J Lukin, S Giusti, N Unsain, A Cáceres, F Steiner, P Tinnefeld, D Refojo, T M Jovin, F D Stefani Super-resolution Imaging of Energy Transfer by Intensity-Based STED-FRET Journal Article Nano Letters, 2021, ISSN: 1530-6984. Abstract \| Links \| Tags: Foundry Organic, Molecularly-Functionalized @article{, title = {Super-resolution Imaging of Energy Transfer by Intensity-Based STED-FRET}, author = {A M Molszalai and B Siarry and J Lukin and S Giusti and N Unsain and A C\'{a}ceres and F Steiner and P Tinnefeld and D Refojo and T M Jovin and F D Stefani}, url = {https://doi.org/10.1021/acs.nanolett.1c00158}, doi = {10.1021/acs.nanolett.1c00158}, issn = {1530-6984}, year = {2021}, date = {2021-02-23}, journal = {Nano Letters}, abstract = {F\"{o}rster resonance energy transfer (FRET) imaging methods provide unique insight into the spatial distribution of energy transfer and (bio)molecular interaction events, though they deliver average information for an ensemble of events included in a diffraction-limited volume. Coupling super-resolution fluorescence microscopy and FRET has been a challenging and elusive task. Here, we present STED-FRET, a method of general applicability to obtain super-resolved energy transfer images. In addition to higher spatial resolution, STED-FRET provides a more accurate quantification of interaction and has the capacity of suppressing contributions of noninteracting partners, which are otherwise masked by averaging in conventional imaging. The method capabilities were first demonstrated on DNA-origami model systems, verified on uniformly double-labeled microtubules, and then utilized to image biomolecular interactions in the membrane-associated periodic skeleton (MPS) of neurons.}, keywords = {Foundry Organic, Molecularly-Functionalized}, pubstate = {published}, tppubtype = {article} } Close Förster resonance energy transfer (FRET) imaging methods provide unique insight into the spatial distribution of energy transfer and (bio)molecular interaction events, though they deliver average information for an ensemble of events included in a diffraction-limited volume. Coupling super-resolution fluorescence microscopy and FRET has been a challenging and elusive task. Here, we present STED-FRET, a method of general applicability to obtain super-resolved energy transfer images. In addition to higher spatial resolution, STED-FRET provides a more accurate quantification of interaction and has the capacity of suppressing contributions of noninteracting partners, which are otherwise masked by averaging in conventional imaging. The method capabilities were first demonstrated on DNA-origami model systems, verified on uniformly double-labeled microtubules, and then utilized to image biomolecular interactions in the membrane-associated periodic skeleton (MPS) of neurons. Close https://doi.org/10.1021/acs.nanolett.1c00158 doi:10.1021/acs.nanolett.1c00158 Close
213.	J Kussmann, H Laqua, C Ochsenfeld Highly Efficient Resolution-of-Identity Density Functional Theory Calculations on Central and Graphics Processing Units Journal Article Journal of Chemical Theory and Computation, 2021, ISSN: 1549-9618. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Highly Efficient Resolution-of-Identity Density Functional Theory Calculations on Central and Graphics Processing Units}, author = {J Kussmann and H Laqua and C Ochsenfeld}, url = {https://doi.org/10.1021/acs.jctc.0c01252}, doi = {10.1021/acs.jctc.0c01252}, issn = {1549-9618}, year = {2021}, date = {2021-02-22}, journal = {Journal of Chemical Theory and Computation}, abstract = {We present an efficient method to evaluate Coulomb potential matrices using the resolution of identity approximation and semilocal exchange-correlation potentials on central (CPU) and graphics processing units (GPU). The new GPU-based RI-algorithm shows a high performance and ensures the favorable scaling with increasing basis set size as the conventional CPU-based method. Furthermore, our method is based on the J-engine algorithm [White; , Head-Gordon, J. Chem. Phys. 1996, 7, 2620], which allows for further optimizations that also provide a significant improvement of the corresponding CPU-based algorithm. Due to the increased performance for the Coulomb evaluation, the calculation of the exchange-correlation potential of density functional theory on CPUs quickly becomes a bottleneck to the overall computational time. Hence, we also present a GPU-based algorithm to evaluate the exchange-correlation terms, which results in an overall high-performance method for density functional calculations. The algorithms to evaluate the potential and nuclear derivative terms are discussed, and their performance on CPUs and GPUs is demonstrated for illustrative calculations.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close We present an efficient method to evaluate Coulomb potential matrices using the resolution of identity approximation and semilocal exchange-correlation potentials on central (CPU) and graphics processing units (GPU). The new GPU-based RI-algorithm shows a high performance and ensures the favorable scaling with increasing basis set size as the conventional CPU-based method. Furthermore, our method is based on the J-engine algorithm [White; , Head-Gordon, J. Chem. Phys. 1996, 7, 2620], which allows for further optimizations that also provide a significant improvement of the corresponding CPU-based algorithm. Due to the increased performance for the Coulomb evaluation, the calculation of the exchange-correlation potential of density functional theory on CPUs quickly becomes a bottleneck to the overall computational time. Hence, we also present a GPU-based algorithm to evaluate the exchange-correlation terms, which results in an overall high-performance method for density functional calculations. The algorithms to evaluate the potential and nuclear derivative terms are discussed, and their performance on CPUs and GPUs is demonstrated for illustrative calculations. Close https://doi.org/10.1021/acs.jctc.0c01252 doi:10.1021/acs.jctc.0c01252 Close
212.	M Peschel, P Kabacinski, D P Schwinger, E Thyrhaug, G Cerullo, T Bach, J Hauer, De R Vivie-Riedle Activation of 2-Cyclohexenone by BF3 Coordination: Mechanistic Insights from Theory and Experiment Journal Article Angewandte Chemie International Edition, n/a (n/a), 2021, ISSN: 1433-7851. Abstract \| Links \| Tags: Molecularly-Functionalized, Solid-Liquid @article{, title = {Activation of 2-Cyclohexenone by BF3 Coordination: Mechanistic Insights from Theory and Experiment}, author = {M Peschel and P Kabacinski and D P Schwinger and E Thyrhaug and G Cerullo and T Bach and J Hauer and De R Vivie-Riedle}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202016653}, doi = {https://doi.org/10.1002/anie.202016653}, issn = {1433-7851}, year = {2021}, date = {2021-02-17}, journal = {Angewandte Chemie International Edition}, volume = {n/a}, number = {n/a}, abstract = {Lewis acids have recently been recognized as catalysts enabling enantioselective photochemical transformations. Mechanistic studies on these systems are however rare, either due to their absorption at wavelengths shorter than 260 nm, or due to the limitations of theoretical dynamic studies for larger complexes. In this work, we overcome these challenges and employ sub-30-fs transient absorption in the UV, in combination with a highly accurate theoretical treatment on the XMS-CASPT2 level. We investigate 2-cyclohexenone and its complex to boron trifluoride and analyze the observed dynamics based on trajectory calculations including non-adiabatic coupling and intersystem crossing. This approach explains all ultrafast decay pathways observed in the complex. We show that the Lewis acid remains attached to the substrate in the triplet state, which in turn explains why chiral boron-based Lewis acids induce a high enantioselectivity in photocycloaddition reactions.}, keywords = {Molecularly-Functionalized, Solid-Liquid}, pubstate = {published}, tppubtype = {article} } Close Lewis acids have recently been recognized as catalysts enabling enantioselective photochemical transformations. Mechanistic studies on these systems are however rare, either due to their absorption at wavelengths shorter than 260 nm, or due to the limitations of theoretical dynamic studies for larger complexes. In this work, we overcome these challenges and employ sub-30-fs transient absorption in the UV, in combination with a highly accurate theoretical treatment on the XMS-CASPT2 level. We investigate 2-cyclohexenone and its complex to boron trifluoride and analyze the observed dynamics based on trajectory calculations including non-adiabatic coupling and intersystem crossing. This approach explains all ultrafast decay pathways observed in the complex. We show that the Lewis acid remains attached to the substrate in the triplet state, which in turn explains why chiral boron-based Lewis acids induce a high enantioselectivity in photocycloaddition reactions. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202016653 doi:https://doi.org/10.1002/anie.202016653 Close
211.	J Kröger, A Jiménez-Solano, G Savasci, P Rovó, I Moudrakovski, K Küster, H Schlomberg, H A Vignolo-González, V Duppel, L Grunenberg, C B Dayan, M Sitti, F Podjaski, C Ochsenfeld, B V Lotsch Photocatalytic Hydrogen Evolution: Interfacial Engineering for Improved Photocatalysis in a Charge Storing 2D Carbon Nitride: Melamine Functionalized Poly(heptazine imide) (Adv. Energy Mater. 6/2021) Journal Article Advanced Energy Materials, 11 (6), pp. 2170028, 2021, ISSN: 1614-6832. Abstract \| Links \| Tags: Molecularly-Functionalized @article{, title = {Photocatalytic Hydrogen Evolution: Interfacial Engineering for Improved Photocatalysis in a Charge Storing 2D Carbon Nitride: Melamine Functionalized Poly(heptazine imide) (Adv. Energy Mater. 6/2021)}, author = {J Kr\"{o}ger and A Jim\'{e}nez-Solano and G Savasci and P Rov\'{o} and I Moudrakovski and K K\"{u}ster and H Schlomberg and H A Vignolo-Gonz\'{a}lez and V Duppel and L Grunenberg and C B Dayan and M Sitti and F Podjaski and C Ochsenfeld and B V Lotsch}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202170028}, doi = {https://doi.org/10.1002/aenm.202170028}, issn = {1614-6832}, year = {2021}, date = {2021-02-11}, journal = {Advanced Energy Materials}, volume = {11}, number = {6}, pages = {2170028}, abstract = {In article number 2003016, Bettina V. Lotsch and co-workers demonstrate that covalent surface modifications of the 2D carbon nitride poly(heptazine imide) with melamine groups strongly influence its polarity and photo(electrochemical) properties. This potent tuning pathway also results in the boosting of photocatalytic hydrogen evolution due to increased donor interactions and enhanced hole extraction.}, keywords = {Molecularly-Functionalized}, pubstate = {published}, tppubtype = {article} } Close In article number 2003016, Bettina V. Lotsch and co-workers demonstrate that covalent surface modifications of the 2D carbon nitride poly(heptazine imide) with melamine groups strongly influence its polarity and photo(electrochemical) properties. This potent tuning pathway also results in the boosting of photocatalytic hydrogen evolution due to increased donor interactions and enhanced hole extraction. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/aenm.202170028 doi:https://doi.org/10.1002/aenm.202170028 Close
210.	K Trofymchuk, V Glembockyte, L Grabenhorst, F Steiner, C Vietz, C Close, M Pfeiffer, L Richter, M L Schütte, F Selbach, R Yaadav, J Zähringer, Q Wei, A Ozcan, B Lalkens, G P Acuna, P Tinnefeld Addressable nanoantennas with cleared hotspots for single-molecule detection on a portable smartphone microscope Journal Article Nature Communications, 12 (1), pp. 950, 2021, ISSN: 2041-1723. Abstract \| Links \| Tags: Molecularly-Functionalized @article{, title = {Addressable nanoantennas with cleared hotspots for single-molecule detection on a portable smartphone microscope}, author = {K Trofymchuk and V Glembockyte and L Grabenhorst and F Steiner and C Vietz and C Close and M Pfeiffer and L Richter and M L Sch\"{u}tte and F Selbach and R Yaadav and J Z\"{a}hringer and Q Wei and A Ozcan and B Lalkens and G P Acuna and P Tinnefeld}, url = {https://doi.org/10.1038/s41467-021-21238-9}, doi = {10.1038/s41467-021-21238-9}, issn = {2041-1723}, year = {2021}, date = {2021-02-11}, journal = {Nature Communications}, volume = {12}, number = {1}, pages = {950}, abstract = {The advent of highly sensitive photodetectors and the development of photostabilization strategies made detecting the fluorescence of single molecules a routine task in many labs around the world. However, to this day, this process requires cost-intensive optical instruments due to the truly nanoscopic signal of a single emitter. Simplifying single-molecule detection would enable many exciting applications, e.g., in point-of-care diagnostic settings, where costly equipment would be prohibitive. Here, we introduce addressable NanoAntennas with Cleared HOtSpots (NACHOS) that are scaffolded by DNA origami nanostructures and can be specifically tailored for the incorporation of bioassays. Single emitters placed in NACHOS emit up to 461-fold (average of 89 ± 7-fold) brighter enabling their detection with a customary smartphone camera and an 8-US-dollar objective lens. To prove the applicability of our system, we built a portable, battery-powered smartphone microscope and successfully carried out an exemplary single-molecule detection assay for DNA specific to antibiotic-resistant Klebsiella pneumonia on the road.}, keywords = {Molecularly-Functionalized}, pubstate = {published}, tppubtype = {article} } Close The advent of highly sensitive photodetectors and the development of photostabilization strategies made detecting the fluorescence of single molecules a routine task in many labs around the world. However, to this day, this process requires cost-intensive optical instruments due to the truly nanoscopic signal of a single emitter. Simplifying single-molecule detection would enable many exciting applications, e.g., in point-of-care diagnostic settings, where costly equipment would be prohibitive. Here, we introduce addressable NanoAntennas with Cleared HOtSpots (NACHOS) that are scaffolded by DNA origami nanostructures and can be specifically tailored for the incorporation of bioassays. Single emitters placed in NACHOS emit up to 461-fold (average of 89 ± 7-fold) brighter enabling their detection with a customary smartphone camera and an 8-US-dollar objective lens. To prove the applicability of our system, we built a portable, battery-powered smartphone microscope and successfully carried out an exemplary single-molecule detection assay for DNA specific to antibiotic-resistant Klebsiella pneumonia on the road. Close https://doi.org/10.1038/s41467-021-21238-9 doi:10.1038/s41467-021-21238-9 Close
209.	S Wang, Yousefi A A Amin, L Wu, M Cao, Q Zhang, T Ameri Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications Journal Article Small Structures, n/a (n/a), pp. 2000124, 2021, ISSN: 2688-4062. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Perovskite Nanocrystals: Synthesis, Stability, and Optoelectronic Applications}, author = {S Wang and Yousefi A A Amin and L Wu and M Cao and Q Zhang and T Ameri}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/sstr.202000124}, doi = {https://doi.org/10.1002/sstr.202000124}, issn = {2688-4062}, year = {2021}, date = {2021-02-07}, journal = {Small Structures}, volume = {n/a}, number = {n/a}, pages = {2000124}, abstract = {Metal halide perovskite (MHP) materials, named as the game changers, have attracted researchers’ attention worldwide for over a decade. Among them, nanometer-scale perovskite nanocrystals (PNCs) have exhibited attractive photophysical properties, such as tunable bandgaps, narrow emission, strong light-absorption coefficients, and high defect tolerance, because they combined the excellent optoelectronic properties of bulk perovskite materials with strong quantum confinement effects of the nanoscale. These materials possess a great potential to be applied in the optoelectronic devices. For commercial applications in devices like solar cells (SCs), light-emitting diodes (LEDs), and photodetectors (PDs), the stability of PNCs against ambient atmosphere like oxygen and moisture, as well as light and high temperature is crucial. Herein, the synthetic methods and stability issues of the PNCs are introduced first, followed by the introduction of the strategies for improving their stability by encapsulation. The applications of PNCs in various optoelectronic devices are then briefly presented. Finally, the remained challenges in improving the stability of PNCs toward the PNC-based optoelectronics with high performance and great durability are addressed.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Metal halide perovskite (MHP) materials, named as the game changers, have attracted researchers’ attention worldwide for over a decade. Among them, nanometer-scale perovskite nanocrystals (PNCs) have exhibited attractive photophysical properties, such as tunable bandgaps, narrow emission, strong light-absorption coefficients, and high defect tolerance, because they combined the excellent optoelectronic properties of bulk perovskite materials with strong quantum confinement effects of the nanoscale. These materials possess a great potential to be applied in the optoelectronic devices. For commercial applications in devices like solar cells (SCs), light-emitting diodes (LEDs), and photodetectors (PDs), the stability of PNCs against ambient atmosphere like oxygen and moisture, as well as light and high temperature is crucial. Herein, the synthetic methods and stability issues of the PNCs are introduced first, followed by the introduction of the strategies for improving their stability by encapsulation. The applications of PNCs in various optoelectronic devices are then briefly presented. Finally, the remained challenges in improving the stability of PNCs toward the PNC-based optoelectronics with high performance and great durability are addressed. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/sstr.202000124 doi:https://doi.org/10.1002/sstr.202000124 Close
208.	A Henning, J D Bartl, A Zeidler, S Qian, O Bienek, C-M Jiang, C Paulus, B Rieger, M Stutzmann, I D Sharp Aluminum Oxide at the Monolayer Limit via Oxidant-free Plasma-Assisted Atomic Layer Deposition on GaN Journal Article arXiv preprint arXiv:2102.03642, 2021. Tags: Foundry Inorganic @article{, title = {Aluminum Oxide at the Monolayer Limit via Oxidant-free Plasma-Assisted Atomic Layer Deposition on GaN}, author = {A Henning and J D Bartl and A Zeidler and S Qian and O Bienek and C-M Jiang and C Paulus and B Rieger and M Stutzmann and I D Sharp}, year = {2021}, date = {2021-02-06}, journal = {arXiv preprint arXiv:2102.03642}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close
207.	L Katzenmeier, S Helmer, S Braxmeier, E Knobbe, A S Bandarenka Properties of the Space Charge Layers Formed in Li-Ion Conducting Glass Ceramics Journal Article ACS Applied Materials & Interfaces, 13 (4), pp. 5853-5860, 2021, ISSN: 1944-8244. Abstract \| Links \| Tags: Solid-Solid @article{, title = {Properties of the Space Charge Layers Formed in Li-Ion Conducting Glass Ceramics}, author = {L Katzenmeier and S Helmer and S Braxmeier and E Knobbe and A S Bandarenka}, url = {https://doi.org/10.1021/acsami.0c21304}, doi = {10.1021/acsami.0c21304}, issn = {1944-8244}, year = {2021}, date = {2021-02-03}, journal = {ACS Applied Materials & Interfaces}, volume = {13}, number = {4}, pages = {5853-5860}, abstract = {For years, the space charge layer formation in Li-conducting solid electrolytes and its relevance to so-called all solid-state batteries have been controversially discussed from experimental and theoretical perspectives. In this work, we observe the phenomenon of space charge layer formation using impedance spectroscopy at different electrode polarizations. We analyze the properties of these space charge layers using a physical equivalent circuit describing the response of the solid electrolytes and solid/solid electrified interfaces under blocking conditions. The elements corresponding to the interfacial layers are identified and analyzed with different electrode metals and applied biases. The effective thickness of the space charge layer was calculated to be ∼60 nm at a bias potential of 1 V. In addition, it was possible to estimate the relative permittivity of the electrolytes, specific resistance of the space charge layer, and the effective thickness of the electric double layer (∼0.7 nm).}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close For years, the space charge layer formation in Li-conducting solid electrolytes and its relevance to so-called all solid-state batteries have been controversially discussed from experimental and theoretical perspectives. In this work, we observe the phenomenon of space charge layer formation using impedance spectroscopy at different electrode polarizations. We analyze the properties of these space charge layers using a physical equivalent circuit describing the response of the solid electrolytes and solid/solid electrified interfaces under blocking conditions. The elements corresponding to the interfacial layers are identified and analyzed with different electrode metals and applied biases. The effective thickness of the space charge layer was calculated to be ∼60 nm at a bias potential of 1 V. In addition, it was possible to estimate the relative permittivity of the electrolytes, specific resistance of the space charge layer, and the effective thickness of the electric double layer (∼0.7 nm). Close https://doi.org/10.1021/acsami.0c21304 doi:10.1021/acsami.0c21304 Close
206.	M Ogura, D Han, M M Pointner, L S Junkers, S S Rudel, W Schnick, H Ebert Electronic properties of semiconducting Zn(Si, Ge, Sn)N2 alloys Journal Article Physical Review Materials, 5 (2), pp. 024601, 2021. Links \| Tags: Solid-Solid @article{, title = {Electronic properties of semiconducting Zn(Si, Ge, Sn)N2 alloys}, author = {M Ogura and D Han and M M Pointner and L S Junkers and S S Rudel and W Schnick and H Ebert}, url = {https://link.aps.org/doi/10.1103/PhysRevMaterials.5.024601}, doi = {10.1103/PhysRevMaterials.5.024601}, year = {2021}, date = {2021-02-02}, journal = {Physical Review Materials}, volume = {5}, number = {2}, pages = {024601}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close https://link.aps.org/doi/10.1103/PhysRevMaterials.5.024601 doi:10.1103/PhysRevMaterials.5.024601 Close
205.	F Pielnhofer, L Diehl, A Jiménez-Solano, A Bussmann-Holder, J C Schön, B V Lotsch Examination of possible high-pressure candidates of SnTiO3: The search for novel ferroelectric materials Journal Article APL Materials, 9 (2), pp. 021103, 2021. Links \| Tags: Solid-Solid @article{, title = {Examination of possible high-pressure candidates of SnTiO3: The search for novel ferroelectric materials}, author = {F Pielnhofer and L Diehl and A Jim\'{e}nez-Solano and A Bussmann-Holder and J C Sch\"{o}n and B V Lotsch}, url = {https://aip.scitation.org/doi/abs/10.1063/5.0029968}, doi = {10.1063/5.0029968}, year = {2021}, date = {2021-02-02}, journal = {APL Materials}, volume = {9}, number = {2}, pages = {021103}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close https://aip.scitation.org/doi/abs/10.1063/5.0029968 doi:10.1063/5.0029968 Close
204.	M R P Pielmeier, T Nilges Formation Mechanisms for Phosphorene and SnIP Journal Article Angewandte Chemie International Edition, n/a (n/a), 2021, ISSN: 1433-7851. Abstract \| Links \| Tags: Foundry Inorganic @article{, title = {Formation Mechanisms for Phosphorene and SnIP}, author = {M R P Pielmeier and T Nilges}, url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202016257}, doi = {https://doi.org/10.1002/anie.202016257}, issn = {1433-7851}, year = {2021}, date = {2021-01-29}, journal = {Angewandte Chemie International Edition}, volume = {n/a}, number = {n/a}, abstract = {Abstract Phosphorene\textemdashthe monolayered material of the element allotrope black phosphorus (Pblack)\textemdashand SnIP are 2D and 1D semiconductors with intriguing physical properties. Pblack and SnIP have in common that they can be synthesized via short way transport or mineralization using tin, tin(IV) iodide and amorphous red phosphorus. This top-down approach is the most important access route to phosphorene. The two preparation routes are closely connected and differ mainly in reaction temperature and molar ratios of starting materials. Many speculative intermediates or activator side phases have been postulated especially for top-down Pblack/phosphorene synthesis, such as Hittorf's phosphorus or Sn24P19.3I8 clathrate. The importance of phosphorus-based 2D and 1D materials for energy conversion, storage, and catalysis inspired us to elucidate the formation mechanisms of these two compounds. Herein, we report on the reaction mechanisms of Pblack/phosphorene and SnIP from P4 and SnI2 via direct gas phase formation.}, keywords = {Foundry Inorganic}, pubstate = {published}, tppubtype = {article} } Close Abstract Phosphorene—the monolayered material of the element allotrope black phosphorus (Pblack)—and SnIP are 2D and 1D semiconductors with intriguing physical properties. Pblack and SnIP have in common that they can be synthesized via short way transport or mineralization using tin, tin(IV) iodide and amorphous red phosphorus. This top-down approach is the most important access route to phosphorene. The two preparation routes are closely connected and differ mainly in reaction temperature and molar ratios of starting materials. Many speculative intermediates or activator side phases have been postulated especially for top-down Pblack/phosphorene synthesis, such as Hittorf's phosphorus or Sn24P19.3I8 clathrate. The importance of phosphorus-based 2D and 1D materials for energy conversion, storage, and catalysis inspired us to elucidate the formation mechanisms of these two compounds. Herein, we report on the reaction mechanisms of Pblack/phosphorene and SnIP from P4 and SnI2 via direct gas phase formation. Close https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202016257 doi:https://doi.org/10.1002/anie.202016257 Close
203.	D Han, H Ebert Identification of Potential Optoelectronic Applications for Metal Thiophosphates Journal Article ACS Applied Materials & Interfaces, 13 (3), pp. 3836-3844, 2021, ISSN: 1944-8244. Abstract \| Links \| Tags: Solid-Solid @article{, title = {Identification of Potential Optoelectronic Applications for Metal Thiophosphates}, author = {D Han and H Ebert}, url = {https://doi.org/10.1021/acsami.0c17818}, doi = {10.1021/acsami.0c17818}, issn = {1944-8244}, year = {2021}, date = {2021-01-27}, journal = {ACS Applied Materials & Interfaces}, volume = {13}, number = {3}, pages = {3836-3844}, abstract = {Metal thiophosphates are a large family of compounds that received far less attention than conventional chalcogenides. Recently, however, metal thiophosphates arouse research interest in regard of energy harvesting and conversion due to their structural and chemical diversity. Nevertheless, there remain many unexplored metal thiophosphates. Here, we performed a comprehensive investigation on the electronic and optoelectronic properties of a series of metal thiophosphates using first-principles calculations and identified several highly promising compounds as p-type transparent conductors, photovoltaic absorbers, and single visible-light-driven photocatalysts for water splitting. Our investigation reveals the intrinsic features of a series of typical metal thiophosphates, identifies their new optoelectronic applications, and validates that metal thiophosphates are promising materials deserving exploration.}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close Metal thiophosphates are a large family of compounds that received far less attention than conventional chalcogenides. Recently, however, metal thiophosphates arouse research interest in regard of energy harvesting and conversion due to their structural and chemical diversity. Nevertheless, there remain many unexplored metal thiophosphates. Here, we performed a comprehensive investigation on the electronic and optoelectronic properties of a series of metal thiophosphates using first-principles calculations and identified several highly promising compounds as p-type transparent conductors, photovoltaic absorbers, and single visible-light-driven photocatalysts for water splitting. Our investigation reveals the intrinsic features of a series of typical metal thiophosphates, identifies their new optoelectronic applications, and validates that metal thiophosphates are promising materials deserving exploration. Close https://doi.org/10.1021/acsami.0c17818 doi:10.1021/acsami.0c17818 Close
202.	A Hötger, J Klein, K Barthelmi, L Sigl, F Sigger, W Männer, S Gyger, M Florian, M Lorke, F Jahnke, T Taniguchi, K Watanabe, K D Jöns, U Wurstbauer, C Kastl, K Müller, J J Finley, A W Holleitner Gate-Switchable Arrays of Quantum Light Emitters in Contacted Monolayer MoS2 van der Waals Heterodevices Journal Article Nano Letters, 21 (2), pp. 1040-1046, 2021, ISSN: 1530-6984. Abstract \| Links \| Tags: Solid-Solid @article{, title = {Gate-Switchable Arrays of Quantum Light Emitters in Contacted Monolayer MoS2 van der Waals Heterodevices}, author = {A H\"{o}tger and J Klein and K Barthelmi and L Sigl and F Sigger and W M\"{a}nner and S Gyger and M Florian and M Lorke and F Jahnke and T Taniguchi and K Watanabe and K D J\"{o}ns and U Wurstbauer and C Kastl and K M\"{u}ller and J J Finley and A W Holleitner}, url = {https://doi.org/10.1021/acs.nanolett.0c04222}, doi = {10.1021/acs.nanolett.0c04222}, issn = {1530-6984}, year = {2021}, date = {2021-01-27}, journal = {Nano Letters}, volume = {21}, number = {2}, pages = {1040-1046}, abstract = {We demonstrate electrostatic switching of individual, site-selectively generated matrices of single photon emitters (SPEs) in MoS2 van der Waals heterodevices. We contact monolayers of MoS2 in field-effect devices with graphene gates and hexagonal boron nitride as the dielectric and graphite as bottom gates. After the assembly of such gate-tunable heterodevices, we demonstrate how arrays of defects, that serve as quantum emitters, can be site-selectively generated in the monolayer MoS2 by focused helium ion irradiation. The SPEs are sensitive to the charge carrier concentration in the MoS2 and switch on and off similar to the neutral exciton in MoS2 for moderate electron doping. The demonstrated scheme is a first step for producing scalable, gate-addressable, and gate-switchable arrays of quantum light emitters in MoS2 heterostacks.}, keywords = {Solid-Solid}, pubstate = {published}, tppubtype = {article} } Close We demonstrate electrostatic switching of individual, site-selectively generated matrices of single photon emitters (SPEs) in MoS2 van der Waals heterodevices. We contact monolayers of MoS2 in field-effect devices with graphene gates and hexagonal boron nitride as the dielectric and graphite as bottom gates. After the assembly of such gate-tunable heterodevices, we demonstrate how arrays of defects, that serve as quantum emitters, can be site-selectively generated in the monolayer MoS2 by focused helium ion irradiation. The SPEs are sensitive to the charge carrier concentration in the MoS2 and switch on and off similar to the neutral exciton in MoS2 for moderate electron doping. The demonstrated scheme is a first step for producing scalable, gate-addressable, and gate-switchable arrays of quantum light emitters in MoS2 heterostacks. Close https://doi.org/10.1021/acs.nanolett.0c04222 doi:10.1021/acs.nanolett.0c04222 Close

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