Coordination Engineering in Cobalt-Nitrogen-Functionalized Materials for CO₂ Reduction

Cobalt-nitrogen-functionalized materials have been recognized as promising catalysts for the CO₂ reduction reaction because of their superior activity. In order to further improve their activity, we proposed an optimization method through coordination engineering in cobalt-nitrogen-functionalized porphyrin and graphene. By considering a series of derived structures with coordinating nitrogen atoms substituted by carbon or oxygen atoms, a clear activity trend is obtained by constructing a volcano-type plot for activity against adsorption energies of *CO. Detailed electronic structure analysis shows that the enhanced catalytic activity is due to the lacking of π bonding in Co-O bonds compared to Co-C or Co-N bonds in cobalt-centered motifs. This difference allows us to predict the catalytic activity by using the vacancy formation energy of the cobalt atom. Our work provides a general guideline for a rational design of efficient catalysts, which may stimulate further study of coordination engineering for other key energy conversion processes.