title: Visible light responsive pristine metal oxide photocatalyst: enhancement of activity by crystallization under hydrothermal treatment.
abstract: Photocatalytic activities of amorphous and crystal bismuth tungstate (Bi(2)WO(6)) were investigated using oxidative decomposition of gaseous acetaldehyde under visible light irradiation (>400 nm). Here, for the first time, negligible photocatalytic activity of amorphous Bi(2)WO(6) owing to the fast recombination of electron-hole pairs and the high quantum efficiency of Bi(2)WO(6) crystallites under visible light were demonstrated by action spectrum analysis and time-resolved infrared absorption measurements. Crystallization of the amorphous phase provided a red shift of the photoabsorption edge and marked increase in the lifetime of photoexcited electrons, resulting in an increase of photocatalytic activity.
authors.affiliation: Catalysis Research Center, Hokkaido University, Sapporo 001-0021, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Amano
authors.forename: Akira
authors.initials: A
authors.lastname: Yamakata
authors.forename: Kohei
authors.initials: K
authors.lastname: Nogami
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Osawa
authors.forename: Bunsho
authors.initials: B
authors.lastname: Ohtani