Highly stable water splitting on oxynitride TaON photoanode system under visible light irradiation.

Catalysis Research Center, Hokkaido University, North 21, West 10, Sapporo 001-0021, Japan.
Journal of the American Chemical Society (Impact Factor: 11.44). 04/2012; 134(16):6968-71. DOI: 10.1021/ja302059g
Source: PubMed

ABSTRACT Highly stable photoelectrochemical water splitting is demonstrated for the first time on a tantalum oxynitride (TaON) photoanode under visible light irradiation. Highly dispersed CoO(x) nanoparticles on the TaON photoanode efficiently scavenge photogenerated holes and effectively suppress self-oxidative deactivation of the TaON surface, resulting in a stable photocurrent. The use of highly dispersed CoO(x) cocatalyst on TaON together with phosphate solutions significantly increased the photocurrent due to the formation of a cobalt/phosphate phase. This enabled us to stably split water into H(2) and O(2) under visible light irradiation at a relatively low applied bias (0.6 V vs Pt counter electrode).

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