▎ 摘　　要

CO catalytic oxidation on the two-dimensional (2D) Fe/N-X clusters embedded graphene (G) (X = 4, 3, 2, 1) with D-4h, C-2v, C-2h, and C-S symmetries is investigated using the first-principle method. Fe/N-2-G system with C-2h symmetry facilitates the O-2 adsorption. The strong interaction between the Fe atom and O-2 in Fe/N-2-G system can be contributed from the high energy of Fe's d(z)(2) orbit. The CO oxidation reaction on Fe/N2-G system has a small energy barrier (0.43 eV) by the Langmuir-Hinshelwood (LH) mechanism (CO + O-2 -> OOCO -> CO2 + O-ads), which would be useful in evaluating the reactivity of Fe catalyst and serving as a good candidate for efficient non-noble metal catalyst. The results provide valuable guidance on selecting catalysts of low cost and superior activity to fabricate graphene-based materials.