Efficient water reduction with gallium phosphide nanowires

• DOI: 10.1038/ncomms8824
• Publication Date: 2015-07-17T10:35:54Z
• Authors: Anthony Standing; Simone Assali; Lu Gao; Marcel A. Verheijen; Dick van Dam; Yingchao Cui; Peter H. L. Notten; Jos E. M. Haverkort; Erik P. A. M. Bak...
• Keywords: Gallium phosphide; Wurtzite crystal structure; Photocathode

Photoelectrochemical hydrogen production from solar energy and water offers a clean sustainable fuel option for the future. Planar III/V material systems have shown highest efficiencies, but are expensive. By moving to nanowire regime demand on quantity is reduced, new materials can be uncovered, such as wurtzite gallium phosphide, featuring direct bandgap. This one of few combining large light absorption (close to) ideal band-edge positions full splitting. Here we report photoelectrochemical reduction water, p-type phosphide photocathode. modifying geometry reduce electrical resistance enhance optical absorption, surface with multistep platinum deposition, high current densities open circuit potentials were achieved. Our results demonstrate capabilities this material, even when used in low quantities, nanowires.