Wire-shaped electrode of CdSe-sensitized ZnO nanowire arrays for photoelectrochemical hydrogen generation

We combined CdSe nanoparticles and ZnO nanowire arrays to demonstrate a wire-shaped electrode for photoelectrochemical hydrogen generation illuminated with AM 1.5 spectrum. An array of ZnO nanowires was grown vertically and radially outward from a Cu-wire mesh substrate. CdSe nanoparticles were attached to the surface of the orientated ZnO nanowires. Such wire-shaped electrode with radially outward orientated CdSe/ZnO nanowires provided improved electrolyte mass transport and minimized loss of incident photons. CdSe/ZnO nanowires were formed in all directions over the Cu wire, leading to low incident-light-angle dependence. For photoelectrochemical hydrogen generation under one-sun irradiation, the wire-shaped electrode device outperformed the planar-shaped electrode device by at least 30%.