Enhanced CO2 electroreduction on Co active site of cobalt phthalocyanine by electronic effect

Metal phthalocyanines molecular catalysts exhibit the unique ability of CO2 electrochemical reduction reaction (CO2ERR) thanks to their well-defined macrocycle structure. In this work, we introduced different substituting functional groups at the phthalocyanine ring of cobalt phthalocyanine to study the relationship of molecular structure optimization and CO2ERR activity. An optimal nitro-substituted cobalt phthalocyanine catalyst can mediate CO2 to CO in a H-cell with maximum selectivity of similar to 94% together with a current density of 12.6 mA cm(-2) at -0.877 V vs. RHE. The insights of this work on designing and optimizing of the molecular catalysts contribute to lower energy as well as cost-effective CO2ERR.

Automated summary

Metal phthalocyanines molecular catalysts demonstrate unique ability in CO2 electrochemical reduction reaction (CO2ERR) due to their well-defined macrocycle structure. By introducing different substituent functional groups on the phthalocyanine ring of cobalt phthalocyanine, the relationship between molecular structure optimization and CO2ERR activity was studied. An optimal nitro-substituted cobalt phthalocyanine catalyst can achieve high selectivity of 94% in converting CO2 to CO, with a current density of 12.6 mA cm(-2) at -0.877 V vs. RHE. Insights gained from this study on designing and optimizing molecular catalysts contribute to lower energy and cost-effective CO2ERR.