Screening Framework of Metal–N–C Diatomic Catalysts for Electrochemical CO 2 Reduction

Diatomic catalysts (DACs), owing to their reduced cost, high efficiency, and good stability, have emerged as potential catalysts for electrochemical CO 2 reduction (CO 2 RR). While, further development of CO 2 RR DACs is hampered by the limited understanding of their dual-atom catalytic center. This study systematically screens nitrogen-doped graphene-based DACs by incorporating 13 metals by means of density functional theory calculations and machine learning. NiMn–N–C and SnNi–N–C have emerged as candidates for the CO 2 RR, facilitating the production of CO and HCOOH, respectively. The key finding is that NiMn–N–C exhibits catalytic stability over a wide range of pH values and applied potentials, particularly under strongly acidic conditions, compared with other reported DACs. While acidic CO 2 RR performance is hindered by DAC instability and competing hydrogen evolution, NiMn–N–C emerges as a candidate for efficient acidic CO 2 RR applications. The findings offer valuable insights into DAC operational principles, contributing to the rational design of highly efficient catalysts for pH-universal electrolyte CO 2 RR applications.