Identification of Efficient Single-Atom Catalysts Based on V2CO2 MXene by ab Initio Simulations

The first-principles simulations are used to search and identify a potential candidate for the single-atom catalysts (SACs). By exploring the stability, clustering tendency, and catalytic activity of different transition metals (TMs) on the two-dimensional V 2 CO 2 MXene, Zn/V 2 CO 2 is found to be a promising SAC. We also find that the oxygen vacancies are critical for stabilizing the single-atom adsorption and preventing the aggregation of the TMs. CO oxidation on Zn/V 2 CO 2 via Langmuir–Hinshelwood mechanism is both kinetically and thermodynamically favored, with an energy barrier for the rate-limiting step of merely 0.14 eV, indicating that it can act as a promising SAC for low-temperature CO oxidation.