Enhanced photocatalytic CO2 reduction using a trimetallic organic framework as the catalyst under visible light

The photocatalytic reduction of carbon dioxide into high value-added chemical feedstock is significant for mitigation of the energy crisis and the greenhouse effect. Metal–organic frameworks (MOFs) possess broad application prospects in photocatalytic CO2 conversion due to the ability to adjust the metal types in metal cluster nodes. Herein, the CO2 photocatalytic performance of trimetallic Fe0.02Ni0.10–Cox–PCN-250 (x = 0.05, 0.10, 0.15, 0.20 mol) was investigated by adjusting the content of Co. Notably, the photocatalytic yields of Fe0.02Ni0.10–Cox–PCN-250 (x = 0.05, 0.10, 0.15, 0.20 mol) were higher than those of bimetallic Fe0.02Ni0.10–PCN-250 and Fe0.02Co0.10–PCN-250 irradiated by visible light. The optimum yield of CO was obtained by trimetallic Fe0.02Ni0.10–Co0.15–PCN-250, up to 299 μmol g−1 h−1. The enhanced yield of CO might be ascribed to the high CO2 adsorption capacity and photogenerated electron transfer after addition of a suitable amount of the third ion, Co. This study provides new insights by designing trimetallic catalysts to increase the efficiency of photocatalytic CO2 reduction.