A5018552885- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Copper-based nanomaterials and applications
- Crystallography and molecular interactions
- Semiconductor materials and devices
- Inorganic Chemistry and Materials
- Semiconductor materials and interfaces
- Anodic Oxide Films and Nanostructures
- ZnO doping and properties
- Iron-based superconductors research
- Electron and X-Ray Spectroscopy Techniques
- Silicon and Solar Cell Technologies
- Integrated Circuits and Semiconductor Failure Analysis
- Crystal Structures and Properties
- Analytical Chemistry and Chromatography
- Electrochemical Analysis and Applications
- Microfluidic and Capillary Electrophoresis Applications
- Semiconductor Quantum Structures and Devices
- Molecular Junctions and Nanostructures
- Nanocluster Synthesis and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Ga2O3 and related materials
- Cancer-related gene regulation
Technische Universität Berlin
1975-2022
Helmholtz-Zentrum Berlin für Materialien und Energie
2008-2021
Freie Universität Berlin
2007-2021
Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute
1989-2008
Bruker (Germany)
2008
University of Guelph
1976-1991
Colloidal gold particles with core diameters between 5.2 and 14.6 nm are investigated by capillary zone electrophoresis in acetic acid/acetate buffer (pH 5.0) without any sieving additive. It was found that the mobility of a given diameter decreases decreasing ionic strength as thickness electric double layer increases. At highest (6 mmol/L) good linear dependence on reciprocal radius allows size-based characterization nanoparticles. © 1997 John Wiley & Sons, Inc. J Micro Sep 9: 529–534,
ABSTRACT In 2 S 3 buffer layers have been prepared using the spray ion layer gas reaction deposition technique for chalcopyrite‐based thin‐film solar cells. These buffers deposited on commercially available Cu(In,Ga)(S,Se) absorbers resulted in cells with certified record efficiencies of 16.1%, clearly higher than corresponding CdS‐buffered references. The process has optimized, and resulting studied current–voltage quantum efficiency analysis compared previous cells, a thermally evaporated...
22.2% relative enhancement of photocurrent in ultra-thin perovskite solar cells by one step incorporation plasmonic silver nanoparticles.
Wurtzite-phase ZnS nanodot films with controllable dot density can be prepared at low temperature by a technique known as Spray-ILGAR (ILGAR = ion-layer gas reaction), without organic surfactant. nanodots covered homogenous In2S3 (as the point-contact bridge) act defect passivation layer and form structured buffer layer. This ZnS/In2S3 improves cell efficiencies up to about 1%–1.5% compared reference cells pure ILGAR buffer.
In this work, we investigate the p–n junction region for two different buffer/Cu(In,Ga)(Se,S)2 (CIGSSe) samples having conversion efficiencies (the cell with pure In2S3 buffer shows a lower efficiency than nano-ZnS/In2S3 buffered one). To explain better of sample layer, combined transmission electron microscopy, atom probe tomography, and X-ray photoelectron spectroscopy studies were performed. sample, CuIn3Se5 ordered-defect compound is observed at CIGSSe surface, whereas in no such...
The oxidation of methyl viologen, 1,1′-dimethyl-4,4′-bipyridylium chloride (MV2+), in aqueous solution has been carried out γ-radiolytically and photocatalytically (in the presence colloidal titanium dioxide). Two strongly fluorescing products have observed, separated identified: 1′,2′-dihydro-1,1′-dimethyl-2′-oxo-4,4′-bipyridylium cation ['2-one', λflmax(H2O)= 516 nm] 3,4-dihydro-1,1′-dimethyl-3-oxo-4,4′-bipyridylium ['3-one', 528 nm]. Both compounds exhibit characteristic u.v.–visible...
Abstract Für die Synthese der zahlreichen natürlich vorkommenden Furanoeremophilane wird ein weitgehend variierbares Syntheseschema beschrieben. Ausgehend vom Dien‐Addukt 30 gelingt Darstellung von racemischem Ligularon (66). trans‐Furanoerernophil‐9‐011 (76) und Euryopsonol (80) sowie zahlreicher aus Naturstoffen erhaltener Umwandlungsprodukte. Eine eingehende Untersuchung Umwandlungsmöglichkeiten verschiedenen synthetischen Furanoeremophilanen eröffnet Wege für weiterer Naturstoffe. ‐ Die...
The electrical properties of the interface between anodically grown In2O3 and n-type InSb have been studied by constructing MOS-type devices measuring capacitance-voltage characteristic these at 77 K. Oxides having thicknesses 400 9000 Å were prepared anodization constant current in 0.1N KOH. voltage shift experimental ideal theoretical curves is used to find magnitude sign surface state charge metal-semiconductor work-function difference. We that oxides consistently exhibit a positive on...
Abstract Re 6 S 8 Cl 2 single crystals have been synthesized by chemical vapour transport with chlorine as transporting agent. Structure analysis revealed that the material is isomorphous Br and Se but not lamellar . The thermal stability of this semiconducting rhenium cluster compound was simulated a function phase composition thermochemical calculations in ternary system Re–S–Cl at temperatures 1000, 1200 1400 K. Predominance‐area diagrams indicate can coexist ReS depending on pressure...
Abstract This study demonstrates the potential of Raman microscopy in analysis thin film cross‐sections. maps photovoltaic material CuInS 2 (CIS), which was prepared by spray ion layer gas reaction method, revealed spatial distribution two different CIS modifications – chalcopyrite‐type and CuAu I‐type as well contaminants segregates with a lateral resolution approx. 400 nm. Additionally, chemical heterogeneity CuGaSe /CuGa 3 Se 5 bi‐layer stack clearly resolved. provides convenient way to...
Abstract Recyclable gold nanocatalysts with controllable morphology are in‐situ formed on the solid substrate by a facile ultrasonic spray pyrolysis method. The Au nanoparticles Mo substrates form spheres, while Si icosahedra, or after addition of Cu ions to precursor solution, decahedra obtained. catalytic properties studied for reduction 4‐nitrophenol as model reaction and compared those several stabilized colloidal catalysts. Due absence any stabilizers surface good adhesion support,...