A DFT study on the possibility of using a single Cu atom incorporated nitrogen-doped graphene as a promising and highly active catalyst for oxidation of CO

Using dispersion-corrected density functional theory (DFT) calculations, a single Cu adatom incorporated nitrogen-doped graphene (CuN3-Gr) is proposed as a new and highly active noble-metal-free catalyst for carbon monoxide (CO) oxidation reaction. According to our results, the Cu adatom can be stably anchored onto the monovavancy site of the nitrogen-doped graphene, and the resulting large diffusion barrier suggests that the metal clustering is avoided in CuN3-Gr. Three possible reaction mechanisms for CO oxidation (ie, Eley-Rideal, Langmuir-Hinshelwood, and termolecular Eley-Rideal) are systematically studied. It is found that the activation energy for the rate-determining step of the termolecular Eley-Rideal mechanism is only 0.13 eV, which is much smaller than those of others. The results of this study may provide a useful guideline for the design of highly active and promising single-metal catalysts for the CO oxidation reaction based on graphene.