ATR-SEIRAS investigation of the Fermi level of Pt cocatalyst on a GaN photocatalyst for hydrogen evolution under irradiation

Masaaki Yoshida; Akira Yamakata; Kazuhiro Takanabe; Jun Kubota; Masatoshi Osawa; Kazunari Domen

doi:10.1021/ja904991p

ATR-SEIRAS investigation of the Fermi level of Pt cocatalyst on a GaN photocatalyst for hydrogen evolution under irradiation

J Am Chem Soc. 2009 Sep 23;131(37):13218-9. doi: 10.1021/ja904991p.

Authors

Masaaki Yoshida¹, Akira Yamakata, Kazuhiro Takanabe, Jun Kubota, Masatoshi Osawa, Kazunari Domen

Affiliation

¹ Department of Chemical System Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.

PMID: 19715313
DOI: 10.1021/ja904991p

Abstract

The interaction of photogenerated carries in GaN photocatalyst with Pt cocatalyst for hydrogen evolution under irradiation was investigated from in situ ATR-SEIRAS measurement by following the CO vibrational frequency. After irradiation, the CO frequency shifted higher, indicating that the Fermi level of Pt particles was positively shifted by the photogenerated holes. Thereafter, a lower frequency peak appeared, indicating that the Fermi level of some Pt particles was negatively shifted to the hydrogen evolution potential by photogenerated electrons, which is the essential function of cocatalysis for hydrogen evolution.