β-Ga₂O₃ Single Crystal as a Photoelectrode for Water Splitting

• Takayoshi Oshima

• Kenichi Kaminaga

• Hisanori Mashiko

• Akira Mukai

• Kohei Sasaki

• Takekazu Masui

• Akito Kuramata

• Shigenobu Yamakoshi

• Akira Ohtomo

Abstract

We report the photoelectrode properties of an n-type β-Ga 2 O 3 single crystal in aqueous solutions. The conduction and valence band-edge potentials were found to be 1.1 V higher and 2.5 V lower than the H + /H 2 and O 2 /H 2 O redox potentials, respectively. Photocurrent drastically increased as photogenerated carriers were excited at a photon energy higher than the fundamental absorption edge of 4.7 eV. The incident photon-to-current conversion efficiency was 36% at 5.2 eV. Gaseous oxygen and hydrogen evolved from the photoelectrode and Pt counter electrode, respectively. The stoichiometric water splitting was demonstrated by applying an external bias of 1 V.

Journal

• Japanese Journal of Applied Physics

  Japanese Journal of Applied Physics 52 (11R), 111102-, 2013-11-01

  IOP Publishing

Keywords

• General Physics and Astronomy
• General Engineering

Details

• CRID: 1360284924864826368
• NII Article ID: 210000143057
• DOI: 10.7567/jjap.52.111102
• ISSN: 13474065
• ISSN: 00214922
• Web Site: https://iopscience.iop.org/article/10.7567/JJAP.52.111102
• Web Site: https://iopscience.iop.org/article/10.7567/JJAP.52.111102/pdf
• Data Source:
  • Crossref
  • CiNii Articles
  • KAKEN