Solar-to-hydrogen efficiency: shining light on photoelectrochemical device performance

Feb. 26, 2017

Abstract Illumination characteristics from artificial sources strongly influence the experimental performance of solar water-splitting devices, with the highest impact on tandem structures designed for optimum conversion efficiency. We highlight quantitative and qualitative flaws of common characterization techniques, discuss their impact on research results and strategy, and demonstrate approaches toward advanced...

A graded catalytic–protective layer for an efficient and stable water-splitting photocathode

Feb. 26, 2017

Abstract Achieving solar-to-hydrogen efficiencies above 15% is key for the commercial success of photoelectrochemical water-splitting devices. While tandem cells can reach those efficiencies, increasing the catalytic activity and long-term stability remains a significant challenge. Here we show that annealing a bilayer of amorphous titanium dioxide (TiO x ) and molybdenum...

Water reduction by a p-GaInP2 photoelectrode stabilized by an amorphous TiO2 coating and a molecular cobalt catalyst

Feb. 26, 2017

Abstract Producing hydrogen through solar water splitting requires the coverage of large land areas. Abundant metal-based molecular catalysts offer scalability, but only if they match noble metal activities. We report on a highly active p-GaInP2 photocathode protected through a 35-nm TiO2 layer functionalized by a cobaloxime molecular catalyst (GaInP2–TiO2–cobaloxime). This...

Semiconductor Interfacial Carrier Dynamics via Photoinduced Electric Fields

Feb. 26, 2017

Abstract Solar photoconversion in semiconductors is driven by charge separation at the interface of the semiconductor and contacting layers. Here we demonstrate that time-resolved photoinduced reflectance from a semiconductor captures interfacial carrier dynamics. We applied this transient photoreflectance method to study charge transfer at p-type gallium-indium phosphide (p-GaInP2) interfaces critically...