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Achieving the goal of generating all of the world's energy via renewable sources and significantly reducing the energy usage will require the development of novel, abundant, nontoxic energy conversion materials. Here, a cost-efficient and scalable continuous flow synthesis of Cs 3 Cu 2 I 5 nanocrystals is developed as a basis for the rapid advancement of novel nanomaterials. Ideal precursor solutions are obtained through a novel batch synthesis, whose product served as a benchmark for the subsequent flow synthesis. Realizing this setup enabled a reproducible fabrication of Cs 3 Cu 2 I 5 nanocrystals. The effect of volumetric flow rate and temperature on the final product's morphology and optical properties are determined, obtaining 21% quantum yield with the optimal configuration. Consequently, the size and morphology of the nanocrystals can be tuned with far more precision and in a much broader range than previously achievable. The flow setup is readily applicable to other relevant nanomaterials. It should enable a rapid determination of a material's potential and subsequently optimize its desired properties for renewable energy generation or efficient optoelectronics., (© 2024 The Author(s). Small published by Wiley‐VCH GmbH.)

CuBi 2 O 4 has recently emerged as a promising photocathode for photo-electrochemical (PEC) water splitting. However, its fast degradation under operation currently poses a limit to its application. Here, we report a novel method to study operando the semiconductor-electrolyte interface during PEC operation by surface-sensitive high-energy X-ray scattering. We find that a fast decrease in the generated photocurrents correlates directly with the formation of a metallic Bi phase. We further show that the slower formation of metallic Cu, as well as the dissolution of the electrode in contact with the electrolyte, further affect the CuBi 2 O 4 activity and morphology. Our study provides a comprehensive picture of the degradation mechanisms affecting CuBi 2 O 4 electrodes under operation and poses the methodological basis to investigate the photocorrosion processes affecting a wide range of PEC materials., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We measured the exciton dynamics in van der Waals heterojunctions of transition metal dichalcogenides (TMDCs) and organic semiconductors (OSs). TMDCs and OSs are semiconducting materials with rich and highly diverse optical and electronic properties. Their heterostructures, exhibiting van der Waals bonding at their interfaces, can be utilized in the field of optoelectronics and photovoltaics. Two types of heterojunctions, MoS 2 -pentacene and WSe 2 -pentacene, were prepared by layer transfer of 20 nm pentacene thin films as well as MoS 2 and WSe 2 monolayer crystals onto Au surfaces. The samples were studied by means of transient absorption spectroscopy in the reflectance mode. We found that A-exciton decay by hole transfer from MoS 2 to pentacene occurs with a characteristic time of 21 ± 3 ps. This is slow compared to previously reported hole transfer times of 6.7 ps in MoS 2 -pentacene junctions formed by vapor deposition of pentacene molecules onto MoS 2 on SiO 2 . The B-exciton decay in WSe 2 shows faster hole transfer rates for WSe 2 -pentacene heterojunctions, with a characteristic time of 7 ± 1 ps. The A-exciton in WSe 2 also decays faster due to the presence of a pentacene overlayer; however, fitting the decay traces did not allow for the unambiguous assignment of the associated decay time. Our work provides important insights into excitonic dynamics in the growing field of TMDC-OS heterojunctions.

Thickness resolved measurements of ambipolar thin-film transistor characteristics track the charging of an organic-organic heterojunction. Combined with structural investigation methods such as AFM and GIXS, this leads to a better understanding of the physics in state of the art devices such as organic solar cells, organic light emitting diodes and light emitting TFTs., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Supported lipid membranes constitute one of the most important model systems for cell membranes. The properties of lipid membranes supported by the hydrophobic solid polymer cyclic olefin copolymer (COC) were investigated. Lipid layers consisting of varying amounts of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP, cationic) and 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC, neutral) prepared by vesicle fusion and solvent exchange were compared. All lipid mixtures coated the COC surface homogeneously forming a fluid membrane as verified by fluorescence microscopy and fluorescence recovery after photobleaching (FRAP). The exact structure of the supported membranes was determined by synchrotron reflectivity experiments using a microfluidic chamber. The X-ray data are in agreement with a compressed (head-to-head distance = 29 angstroms) and less densely packed bilayer.