Photocatalytic reduction of Cr(VI) over TiO_2 nanotubes

In this study TiO2 nanotubes(TiO2NTs) were synthesized using the hydrothermal method,and characterized by XRD,HRTEM and UV-Vis diffuse reflectance spectra.Photocatalytic activity of TiO2 NTs was evaluated by the photocatalytic reduction of Cr(Ⅵ).The dependence of photocatalytic activity of TiO2 NTs on the calcination temperature,pH and cocatalyst loading was studied.The results indicate that TiO2-550 showed the highest photocatalytic activity,and the acidic condition contributes to the reduction of Cr(Ⅵ).In addition,the photocatalytic activity of TiO2-550 was improved by loading with NiO and Co2O3.