La2Sn2O7 enhanced photocatalytic CO2 reduction with H2O by deposition of Au co-catalyst

La2Sn2O7 (LSO) micro/nanospheres, synthesized by a hydrothermal method, exhibited photocatalytic performance for CO2 reduction. The evolution rate of the main reduction products (CH4 and CO) was 0.20 and 0.10 mu mol h(-1), respectively. Loading of Au co-catalyst over La2Sn2O7 efficiently enhanced the photocatalytic activity of CO2 reduction. The highest photocatalytic efficiency was obtained over 1 wt% Au/La2Sn2O7 with an apparent quantum yield (AQY) of 2.54%. Characterization techniques including SEM, TEM, XRD, XPS, DRS, PL, and electrochemical analysis were applied and the physicochemical properties of La2Sn2O7 and Au/La2Sn2O7 samples are discussed. A possible mechanism of photocatalytic CO2 reduction over Au/La2Sn2O7 is proposed.