Density functional theory calculations were performed to explore catalytic activity of BCmNn -doped graphene sheets (Gr-BCmNn; m, n = 0, 1, 2, 3 and m + n = 3) towards the reduction of N2O reductionby CO molecule. Our results indicate that an enhancement in catalytic activity of BN co-doped graphene can be achieved by increasing the number of N atoms coordinated to the B atom. The calculated activation energies reveal that Gr-BCN2 and Gr-BN3 graphene sheets exhibit higher catalytic activity for N2O reduction reduction than Gr-BC3 and Gr-BC2N. These results highlight the possibility to improve the catalytic performance of the graphene by BN co-doping. (C) 2018 Elsevier B.V. All rights reserved.