Preparation, electronic structure and photocatalytic activity of the In₂TiO₅ photocatalyst

Indium titanate In₂TiO₅ powder was prepared by a low-temperature combustion synthesis method and characterized by X-ray powder diffraction, UV-vis diffuse reflectance spectrum and field-emission scanning electron microscope. The only ternary In/Ti/O compound In₂TiO₅, composed of the octahedral [TiO₆] and [InO₆] motifs, was selected to be a photocatalyst containing both early-transition metal (d⁰) and p-block metal (d¹⁰). The absorption spectrum indicates that In₂TiO₅ has an optical gap of 3.02 eV. The photocatalytic property of the sample was evaluated by using the photodegradation of methyl orange (MO). The photocatalytic activity of In₂TiO₅ for the complete degradation of MO was higher than that of TiO₂ (P25). Band calculations reveal that the high photocatalytic activity is tightly related to the electronic structure and the open crystal structure of In₂TiO₅.