%X We present the wafer-scale fabrication of self-catalyzed p-n homojunction 1.7 eV GaAsP core-shell nanowire photocathodes grown on silicon substrates by molecular beam epitaxy with the incorporation of Pt nanoparticles as hydrogen evolution cocatalysts. Under AM 1.5G illumination, the GaAsP nanowire photocathode yielded a photocurrent density of 4.5 mA/cm(2) at 0 V versus a reversible hydrogen electrode and a solar-to-hydrogen conversion efficiency of 0.5%, which are much higher than the values previously reported for wafer-scale III-V nanowire photocathodes. In addition, GaAsP has been found to be more resistant to photocorrosion than InGaP. These results open up a new approach to develop efficient tandem photoelectrochemical devices via fabricating GaAsP nanowires on a silicon platform.
%V 14
%A J Wu
%A Y Li
%A J Kubota
%A K Domen
%A M Aagesen
%A T Ward
%A A Sanchez
%A R Beanland
%A Y Zhang
%A M Tang
%A S Hatch
%A A Seeds
%A H Liu
%N 4
%J Nano Letters
%D 2014
%L discovery1428980
%P 2013-2018
%T Wafer-Scale Fabrication of Self-Catalyzed 1.7 eV GaAsP Core-Shell Nanowire Photocathode on Silicon Substrates
%O This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.