Electronic band structure and photocatalytic activity of M-doped TiO2 (M = Co and Fe)

Abstract

Cobalt- or iron-doped TiO2 nanocrystals were fabricated by the hydrothermal synthesis method. The electronic structure and optical properties of the materials were studied by using XRD, UV-DRS, and the FP-LAPW (Full-Potential Linearized Augmented Plane Wave) method. The bandgap energy of Co- and Fe-doped TiO2 obtained by FP-LAPW and UV-DRS was ca. 2.6 and 2.5 eV, respectively. These doped materials absorbed visible light and exhibited photocatalytic activity for oxidative decomposition of CH3Cl to CO2 under visible light irradiation (lambda > 420 nm). However, only Fe-doped TiO2 showed the activity for CH3Cl degradation to CO2, probably due to its higher oxidation potential, as the FP-LAPW calculation indicated.