Single–atom manganese and nitrogen co-doped graphene as low-cost catalysts for the efficient CO oxidation at room temperature

Abstract Room temperature, low-cost and efficient single-atom catalysts for the CO oxidation was essential for the pollutant-free biological and ecological environment. Herein, the oxidation mechanism of CO on manganese (Mn) and nitrogen (N) co-doped single-vacancy graphene (MnN-SV) and double-vacancy graphene (MnN-DV) are studied through density functional theory (DFT) calculations. The MnN-SV have a more excellent catalytic performance for CO oxidation compared to MnN-DV due to the synergistic effect of the Mn and N atoms and the ligand effect. CO oxidation on MnN-SV results into two CO2 via the termolecular Eley–Rideal (TER) mechanism whose energy barrier of rate determining step (RDS) is 0.351 eV, indicating superior catalytic performance compared to the most known catalysts. In addition, MnN-SV catalyzes CO via the Langmuir-Hinshelwood (LH) mechanism with only an energy barrier of RDS is 0.727 eV, and the energy barrier for the second CO2 generated by Eley-Rideal (ER) mechanism is 0.691 eV. Technologically, present results provide a pathway for the development of an efficient and low-cost catalysts to oxidize CO at room temperature.