Abstract

Transition metal ions(Ni2+, Cr3+ and V5+) doped TiO_2 nanostructured powders were synthesized by mechanical alloying(MA) to shift the adsorption threshold into the visible light region. The synthesized powders were characterized by XRD, SEM, TEM and BET for structural analysis, UV-Vis and photoluminescence spectrum for the optical study. Also, photocatalytic abilities were evaluated by decomposition of 4-chlorophenol(4CP) under ultraviolet and visible light irradiations. Optical studies showed that the absorption wavelength of transition metal ions doped TiO_2 powders moved to visible light range, which was believed to be induced by the energy level change due to the doping. Among the prepared TiO_2 powders, NiO2+ doped TiO_2 powders, showed excellent photooxidative ability in 4CP decomposition.

• Keywords: TiO_2;Mechanical alloying;Photocatalytic activity;