Comprehensive Mechanism of CO2 Electroreduction on Non‐Noble Metal Single‐Atom Catalysts of Mo2CS2‐MXene

In this work, a series of non-noble metal single-atom catalysts of Mo₂ CS₂ -MXene for CO₂ reduction were systematically investigated by well-defined density-functional-theory (DFT) calculations. It is found that nine types of transitional metal (TM) supported Mo₂ CS₂ (TM-Mo₂ CS₂ ) are very stable, while eight can effectively inhibit the competitive hydrogen evolution reaction (HER). After comprehensively comparing the changes of free energy for each pathway in CO₂ reduction reaction (CO₂ RR), it is found that the products of TM-Mo₂ CS₂ are not completely CH₄ . Furthermore, Cr-, Fe-, Co- and Ni-Mo₂ CS₂ are found to render excellent CO₂ RR catalytic activity, and their limiting potentials are in the range of 0.245-0.304 V. In particular, Fe-Mo₂ CS₂ with a nitrogenase-like structure has the lowest limiting potential and the highest electrocatalytic activity. Ab initio molecular dynamics (AIMD) simulations have also proven that these kinds of single-atom catalysts with robust performance could exist stably at room temperature. Therefore, these single TM atoms anchored on the surface of MXenes can be profiled as a promising catalyst for the electrochemical reduction of CO₂ .