Designing N‐Confused Metalloporphyrin‐Based Covalent Organic Frameworks for Enhanced Electrocatalytic Carbon Dioxide Reduction

Abstract Electrochemical conversion of carbon dioxide (CO 2 ) into value‐added products is promising to alleviate greenhouse gas emission and energy demands. Metalloporphyrin‐based covalent organic frameworks (MN 4 ‐Por‐COFs) provide a platform for rational design of electrocatalyst for CO 2 reduction reaction (CO 2 RR). Herein, through systematic quantum‐chemical studies, the N‐confused metallo‐Por‐COFs are reported as novel catalysts for CO 2 RR. For MN 4 ‐Por‐COFs, among the ten 3d metals, M = Co/Cr stands out in catalyzing CO 2 RR to CO or HCOOH; hence, N‐confused Por‐COFs with Co/CrN 3 C 1 and Co/CrN 2 C 2 centers are designed. Calculations indicate CoN x C y ‐Por‐COFs exhibit lower limiting potential (−0.76 and ‐0.60 V) for CO 2 ‐to‐CO reduction than its parent CoN 4 ‐Por‐COFs (−0.89 V) and make it feasible to yield deep‐reduction degree C 1 products CH 3 OH and CH 4 . Electronic structure analysis reveals that substituting CoN 4 to CoN 3 C 1 /CoN 2 C 2 increases the electron density on Co‐atom and raises the d ‐band center, thus stabilizing the key intermediates of the potential determining step and lowering the limiting potential. For similar reason, changing the core from CrN 4 to CrN 3 C 1 /CrN 2 C 2 lowers the limiting potential for CO 2 ‐to‐HCOOH reduction. This work predicts N‐confused Co/CrN x C y ‐Por‐COFs to be high‐performance CO 2 RR catalyst candidates. Inspiringly, as a proof‐of‐concept study, it provides an alternative strategy for coordination regulation and theoretical guidelines for rational design of catalysts.