Two-dimensional porphyrin sheet-supported single-atom manganese catalyst for CO oxidation: A DFT-D study

The mechanism of CO oxidation on two-dimensional porphyrin sheet (TDPS)-supported single atom manganese was studied using density functional theory with dispersion (DFT-D). The molecular dynamics (MD) simulation based on the first principles has been used for confirming Mn-TDPS stability. The energetic calculations indicated that CO and O-2 were favorable to co-adsorb at the active center. Eley-Rideal, Langmuir-Hinshelwood (LH), and tri-molecular Eley-Rideal (TER) mechanisms were used to investigate the reaction pathways of CO oxidation on the Mn-TDPS. Results indicated that the LH and TER reaction mechanisms were feasible due to the small energy barrier of the rate-determining step. Moreover, the oxidation states of the active center of Mn-TDPS affected the reaction barrier and reaction heat, which was unfavorable for CO oxidation in Mn-TDPS. These results findings suggested that Mn-TDPS could be a high activity catalyst for CO oxidation.