Control over Electrochemical CO₂ Reduction Selectivity by Coordination Engineering of Tin Single‐Atom Catalysts

Abstract

Abstract Carbon‐based single‐atom catalysts (SACs) with well‐defined and homogeneously dispersed metal−N 4 moieties provide a great opportunity for CO 2 reduction. However, controlling the binding strength of various reactive intermediates on catalyst surface is necessary to enhance the selectivity to a desired product, and it is still a challenge. In this work, the authors prepared Sn SACs consisting of atomically dispersed SnN 3 O 1 active sites supported on N‐rich carbon matrix (Sn‐NOC) for efficient electrochemical CO 2 reduction. Contrary to the classic Sn‐N 4 configuration which gives HCOOH and H 2 as the predominant products, Sn‐NOC with asymmetric atomic interface of SnN 3 O 1 gives CO as the exclusive product. Experimental results and density functional theory calculations show that the atomic arrangement of SnN 3 O 1 reduces the activation energy for *COO and *COOH formation, while increasing energy barrier for HCOO* formation significantly, thereby facilitating CO 2 ‐to‐CO conversion and suppressing HCOOH production. This work provides a new way for enhancing the selectivity to a specific product by controlling individually the binding strength of each reactive intermediate on catalyst surface.