▎ 摘　　要

It is significative to develop a promising material to efficiently remove poisonous NOx (NO and NO2) gases for environmental conservation. In this work, the density functional theory (DFT) calculations were performed to investigate the adsorption characteristics of seven toxic gases, including CO, H2S, HCN, NH3, NO, NO2 and SO2, on yttrium and three nitrogen co-decorated graphene (YN(3)G), and their electronic, magnetic properties and work function were also discussed. The results show that the YN(3)G has high stability and exhibits a certain metallic feature. The calculated adsorption energies are -2.72 similar to -0.71 eV for those gases and thus they can be stably chemisorbed on YN(3)G. Partial density of states analysis indicates there are strong hybridization between gases, Y-4d and three nitrogen doped graphene (N(3)G), which can be further illustrated by the analysis of charge transfer and charge density difference. In addition, obvious change has taken place for the magnetism of YN(3)G after the NO and NO2 adsorptions. Also, the work functions are apparently increased after NOx adsorption compared with the pristine YN(3)G. Therefore, YN(3)G with excellent capture capacity and sensor ability can be a promising candidate for NOx detection and removal. Our results demonstrate that rare earth doped graphene can also be the family of gas sensor. (C) 2020 Elsevier B.V. All rights reserved.