Iron chalcogenides, in particular iron pyrite, have great potential to be useful materials for cost-effective thin film photovoltaics. However, the performance of pyrite as an absorber material in photovoltaic devices has fallen far short of the theoretical efficiency. A potential cause of this may be the instability of the pyrite phase.
View Article and Find Full Text PDFMg nanocrystals of controllable sizes were prepared in gram quantities by chemical reduction of magnesocene using a reducing solution of potassium with an aromatic hydrocarbon (either biphenyl, phenanthrene, or naphthalene). The hydrogen sorption kinetics were shown to be dramatically faster for nanocrystals with smaller diameters, although the activation energies calculated for hydrogen absorption (115-122 kJ/mol) and desorption (126-160 kJ/mol) were within previously measured values for bulk Mg. This large rate enhancement cannot be explained by the decrease in particle size alone but is likely due to an increase in the defect density present in smaller nanocrystals.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2011
Cu₂ZnSnS₄ (CZTS) nanocrystals, synthesized by a hot injection solution method, have been fabricated into thin films by dip-casting onto fluorine doped tin oxide (FTO) substrates. The photoresponse of the CZTS nanocrystal films was evaluated using absorbance measurements along with photoelectrochemical methods in aqueous electrolytes. Photoelectrochemical characterization revealed a p-type photoresponse when the films were illuminated in an aqueous Eu(3+) redox electrolyte.
View Article and Find Full Text PDFMicrofluidic devices allow for fast detection with little reagent consumption. They also offer portability and the ability to mimic biological systems. Currently, many microfluidic devices are a hybrid of the microchip components, such as flow channels and wells, and larger instrumentation.
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