Efficient Photoreduction of CO2 to CH4 on AgCl/Ag/g-C3N4 Ternary Composites

The AgCl/Ag/g-C3N4 ternary composites were synthesized by simple methods. The characterizations (XRD, FTIR, TEM, UV-DRS, PL) indicated clearly the existence of Ag, AgCl and g-C3N4 phases and visible light absorption ability of composites.The photocatalytic activity was evaluated through photoreduction of CO2 to CH4. The obtained results showed that the composite 3AC-Ag-CN exhibited the highest activity with CH4 production of 3.38.10-2 mmol.g-1.h-1, which was ~7.5 times higher than that of g-C3N4. This activity enhancement was explained by their Z-scheme heterojunction structure.