Assessment of CO2 photoconversion over TiO2/La2O3 treated with acetic acid

Abstract

Abstract TiO2/La2O3 treated with different concentration acetic acid was successfully synthesized via sol-gel method and fumigation. Compared with untreated TiO2/La2O3, acetic acid treated TiO2/La2O3 photocatalysts exhibited higher CO2 conversion efficiency. 0.7\xa0mol L−1 acetic acid functionalized TiO2/La2O3 photocatalyst demonstrated highest CO2 conversion efficiency (97.6%). The mechanism was researched through different characterization methods including HRTEM, FTIR, Py-IR, XPS, et al. The increased performance over TiO2/La2O3 treated with acetic acid for CO2 photoconversion is mainly due to following three factors: (1) more hydroxyls on the surface of photocatalysts promote the adsorption of CO2, (2) the number of hole traps which can inhibit the recombination of photogenerated electrons and holes increases, (3) the formation of active oxygen vacancy\xa0sites is promoted by La2O3 modified and the present of Lewis acidic sites.