Visible light responsive pristine metal oxide photocatalyst: enhancement of activity by crystallization under hydrothermal treatment.
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.
Amano
Fumiaki
F
Catalysis Research Center, Hokkaido University, Sapporo 001-0021, Japan.
Yamakata
Akira
A
Nogami
Kohei
K
Osawa
Masatoshi
M
Ohtani
Bunsho
B