Photocatalysis and solar hydrogen production

Kudo, Akihiko

doi:10.1351/pac200779111917

Pure Appl. Chem., 2007, Vol. 79, No. 11, pp. 1917-1927

http://dx.doi.org/10.1351/pac200779111917

Photocatalysis and solar hydrogen production

Akihiko Kudo^1,2

¹ Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
² Core Research for Evolutional Science and Technology, Japan Science and Technology Agency (CREST, JST), 4-1-8 Honcho, Kawaguchi-shi, Saitama 332-001, Japan

Abstract: Photocatalytic water splitting is a challenging reaction because it is an ultimate solution to energy and environmental issues. Recently, many new powdered photocatalysts for water splitting have been developed. For example, a NiO (0.2 wt %)/NaTaO₃:La (2 %) photocatalyst with a 4.1-eV band gap showed high activity for water splitting into H₂ and O₂ with an apparent quantum yield of 56 % at 270 nm. Overall water splitting under visible light irradiation has been achieved by construction of a Z-scheme photocatalysis system employing visible-light-driven photocatalysts, Ru/SrTiO₃:Rh and BiVO₄ for H₂ and O₂ evolution, and an Fe³⁺/Fe²⁺ redox couple as an electron relay. Moreover, highly efficient sulfide photocatalysts for solar hydrogen production in the presence of electron donors were developed by making solid solutions of ZnS with AgInS₂ and CuInS₂ of narrow band gap semiconductors. Thus, the database of powdered photocatalysts for water splitting has become plentiful.