Shape- and size-selective photocatalytic reactions by layered titanic acidpowder suspended in deaerated aqueous alcohol solutions

Protonic titanate of H(x)Ti(2-x/4)Z(x/4)O(4).H2O (HLe; x similar or equal t o0.7, Z=vacancy) powder of a layered crystal structure was prepared, suspen ded in aqueous alcoholic solutions and photoirradiated by light of waveleng th > 300 nm at room temperature under a deaerated atmosphere. HLe showed ph otocatalytic activity of H-2 production, similar to ordinary titanium(IV) o xide powders. The rate and time course of H-2 evolution by HLe depended str ongly on the kind of alcohol. Detailed investigation revealed that the phot ocatalytic activity was regulated by the shape and size of the alcohol, due to the selection of adsorption at the interlayer of HLe.