Synthesis and photocatalytic properties of iron oxide pillared hydrogen tetratitanate via soft solution chemical routes

Iron oxide pillared H2Ti4O9 was prepared by two different methods, i.e., hydrothermal reaction of H2Ti4O9 in FeSO4 aqueous solution followed by calcining in air and stepwise ion exchange reaction of H2Ti4O9 with n-propylamine aqueous solution and trinuclear ferric iron acetate aqueous solution, followed by UV light irradiation. The samples showed absorption in the visible region and were capable of hydrogen evolution under visible light irradiation (λ>400 nm) in the presence of 0.1 M Na2S aqueous solution as a hole acceptor, although no noticeable hydrogen evolution was observed when H2Ti4O9 and Fe2O3 were used independently. Hydrogen evolution activity of iron oxide pillared tetratitanate fabricated by the hydrothermal crystallization method increased by calcining in air at 300 °C after hydrothermal reaction, and was ca. five times greater than that produced by ion exchange reaction method.