Effects of cocatalysts on photocatalytic properties of La doped Cd2TaGaO6 photocatalysts for hydrogen evolution from ethanol aqueous solution

La doped Cd2TaGaO6 photocatalyst was successfully synthesized for the first time by a sol-gel method. Several metal oxides and noble metals involving NiO, CuO, Cr2O3, Pt, and Ru were respectively loaded onto La doped Cd2TaGaO6 as cocatalyst. NiO and noble metal co-loaded photocatalyst was also prepared. The obtained products were characterized by X-ray diffraction (XRD), ultraviolet-visible spectra (UV-Vis), scanning electron microscope (SEM), etc. The results showed that most of cocatalyst loaded photocatalysts exhibited much higher activities for hydrogen evolution from ethanol aqueous solution than single La doped Cd2TaGaO6. Compared with sole NiO or noble metal loaded photocatalyst, NiO and noble metal co-loaded La doped Cd2TaGaO6 showed superior activity. It is revealed that the loaded NiO and noble metal can interact with each other and cooperate on improving the photocatalytic activity. The effect of the cocatalyst loading amount on photocatalytic properties was discussed. Especially, 0.5 wt% NiO and 0.5 wt% Pt co-loaded La doped Cd2TaGaO6 displayed the highest hydrogen production rate of 2.93 mmol h(-1), which was ca. 33 times that of single La doped Cd2TaGaO6. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.