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 ∼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. © 2021 Elsevier B.V.
Bibliographical noteThis work was supported by the National Natural Science Foundation of China (62004155, 12002271, and 11872302); Scientific Research Project of Shaanxi Provincial Department of Education (20JK0714); Xi'an Science and Technology Plan Project, China (2019220914SYS024CG046).
- CO2 reduction reaction
- Cobalt phthalocyanine
- Electronic effect
- Molecular catalyst