近日，课题组博士生曹守福论文“Understanding the role of central metal and coordination environment of single atom catalysts embedded in graphene flakes on CO₂RR performance”被Journal of Materials Science（2022年中科院SCI期刊三区期刊，IF=4.5）接收！

Abstract:

Single atom catalysts (SACs) are promising for enhancing performance of electrocatalytic CO₂ reduction reaction (CO₂RR). Herein, first-principle calculations were conducted to investigate the mechanism of two electron/proton transfers during CO₂RR on two types of structures of single metal atom with four coordinated nitrogen atoms (M‒N₄, M = Fe, Co, Ni, and Cu), namely metal phthalocyanine (MPc) and metal anchored nitrogen-containing carbon (M‒NC). Our results demonstrate that nitrogen-containing carbon plane effectively immobilizes and activates metal centers. The physical adsorption of CO₂ suggests that the initial activation of CO₂ proceeds through a concerted proton-electron transfer (CPET) step. M‒NC surfaces exhibits higher favorability towards reactions of CO₂ → *COOH and CO₂ → *HCOO compared to MPc with the same metal center. Noteworthily, MPc structures featuring pyrrolic N coordination environment exhibit greater stability, whereas M‒NC with pyridinic N coordination environment demonstrate higher activity in the initial reduction of CO₂. CoPc and Fe‒NC are the optical catalysts for achieving high CO₂RR performance in the formation of CO and HCOOH, respectively. The strong binding of *COOH/*HCOO on catalyst can effectively reduce the reaction energy required for its subsequent reduction. The results of this study provide profound insights into the intricate coordination environment and the distinct role by various metal centers in M‒N_x materials.