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

Abstract

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 μmol 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.