Comparison of optical and structural properties of Cu doped and Cu/Zr co-doped TiO2 nanopowders calcined at various temperatures

TiO2 nanopowders doped with Cu and Zr were prepared via process-controlled sol–gel method. The effects of Zr and Cu doping on the structural and photocatalytic properties of synthesized nanopowders have been studied by X-ray diffraction (XRD), scanning electron microscope, transmission electron microscope, FTIR, and UV–Vis absorption spectroscopy. XRD results suggested that adding dopants has a great effect on crystallinity and particle size of TiO2. Titania rutile phase formation was inhibited by Zr4+ and promoted by Cu2+ doping. The photocatalytic activity was evaluated by degradation kinetics of aqueous methyl orange under visible spectra radiation. The results showed that the photocatalytic activity of the 15 % Zr-doped TiO2 nanopowder has a larger degradation efficiency than 5 % Cu-doped and pure TiO2 under visible light.