title: Wafer-scale fabrication of self-catalyzed 1.7 eV GaAsP core-shell nanowire photocathode on silicon substrates.
abstract: 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.
authors.affiliation: Department of Electronic and Electrical Engineering, University College London , Torrington Place, London WC1E 7JE, United Kingdom.
authors.forename: Jiang
authors.initials: J
authors.lastname: Wu
authors.forename: Yanbo
authors.initials: Y
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Kubota
authors.forename: Kazunari
authors.initials: K
authors.lastname: Domen
authors.forename: Martin
authors.initials: M
authors.lastname: Aagesen
authors.forename: Thomas
authors.initials: T
authors.lastname: Ward
authors.forename: Ana
authors.initials: A
authors.lastname: Sanchez
authors.forename: Richard
authors.initials: R
authors.lastname: Beanland
authors.forename: Yunyan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Mingchu
authors.initials: M
authors.lastname: Tang
authors.forename: Sabina
authors.initials: S
authors.lastname: Hatch
authors.forename: Alwyn
authors.initials: A
authors.lastname: Seeds
authors.forename: Huiyun
authors.initials: H
authors.lastname: Liu