B/N Co‐Doped Graphene for CO 2 Reduction to CH 4 : Role of Co‐Doping and Varied Coordination

ABSTRACT Local coordination plays a crucial role in determining the activity and selectivity of transition‐metal single‐atom catalysts (TM SACs) for the CO 2 reduction reaction (CO 2 RR). Using density functional theory (DFT), we investigate the influence of B and N coordination on the catalytic performance of 3 d TM single atoms (Sc–Zn) stabilized on B/N‐codoped graphene (TM@B x Nᵧ–Gr, x + y = 4). We also look on the role of the adopted DFT functional in predicting the CO 2 RR efficiency of TM SACs supported on B/N‐codoped graphene, by assessing the performance of the widespread PBE functional against the self‐interaction corrected PBE+ U one. Our results show that the stability of TM SACs improves significantly with increasing N content in the coordination environment. Among the 30 TM SAC–support combinations examined, only a limited number are able to effectively activate CO 2 . We further investigate the competition between CO 2 RR and the hydrogen evolution reaction (HER). In addition, we examine the effect of explicit water molecules acting as ligands at the active site. Eventually, Fe@B 3 N–Gr is identified as an efficient catalyst for CO 2 RR to CH 4, and it remains stable under the strongly reducing conditions required for CO 2 RR.