VISIBLE LIGHT DRIVEN CATALYTIC ACTIVITY OF CO-PRECIPITATED CO-DOPED TIO2 PHOTOCATALYST

Co-doped TiO2 nanopowders utilized as photocatalysts were successfully synthesized by co-precipitation method with various Co contents from 0-5 mol% using tetrabutyl titanate and Cobalt (II) nitrate hexahydrate as starting precursors for Ti and Co sources, respectively. Calcination process was conducted in order to improve crystallinity of the powders. The crystal structure and phase formation of both as-precipitated and after-calcined powders were characterized by X-ray diffraction (XRD) while morphologies of the powders were monitored by scanning electron microscope (SEM). Their optical absorptivity and corresponding band gaps were evaluated by diffuse reflectance spectroscopy. The photocatalytic activity of Co-doped TiO2 photocatalysts against aqueous organic dye under visible light were carried out. The influences of Co-dopant and calcination temperature on photocatalytic performance of the catalysts were investigated. It is notified that incorporation of certain content of Co dopant into TiO2 exhibits significant enhancement in its photocatalytic activity under visible light due to extended absorptivity into visible region of the powders with doping.