Fabricated g-C3N4/Ag/m-CeO2 composite photocatalyst for enhanced photoconversion of CO2

In this work, the ordered mesoporous CeO2 (m-CeO2) was successfully fabricated via the nanocasting pathway, through using SBA-15 as a hard template. Besides, g-C3N4/Ag/m-CeO2 composite was successfully constructed by calcination method. Meanwhile, the obtained samples were investigated by series of test techniques. The XRD, SEM and TEM results show that the m-CeO2 and Ag/m-CeO2 with the ordered mesoporous trait. Besides, the EPR, Raman and XPS results suggest that the oxygen vacancies (O-v) and Ce3+ and Ce4+ are in g-C3N4/Ag/m-CeO2. In addition, the ordered mesostructure is favorable for the CO2 molecular movement and adsorption/desorption reaction. The g-C3N4 nanosheets, a promising material possessing suitable conductor band, large specific area, non-toxicity, and outstanding chemical stability, is a candidate semiconductor for CO2 conversion. The introduction of g-C(3)N(4 )nanosheets to Ag/m-CeO2 overcomes the photocorrosion of Ag nanoparticles and Ag facilitate the transfer of photogenerated electrons. The photocatalytic activity results show that when the loading of Ag is 7 wt%, the g-C3N4/7Ag/m-CeO2 composite exhibits the superiority activity for CO2 photoconversion to CO (13.94 mu mol/g) and CH4 (7.39 mu mol/g) under UV-irradiation in 10 h.