▎ 摘　　要

The model of Co3O4 (110B)/defective graphene surface to adsorb NH3 is established. DFT calculation is conducted to study the effects of the defective graphene, Co3O4 (110B) and their coupling effect on adsorption for NH3 and the joint effects of pre-adsorbed O2/H2O on the model. The calculation results reveal the generation of C-Co coupling with Co3O4 (110B) at a specific Cooct site which enhances NH3 adsorption is related to graphene defects. Besides, C-Co coupling promotes the dissociative adsorption of pre-adsorbed O-2 or H2O at Co-oct site with C-Co and thus the formation of oxygen-containing functional groups such as C = O and C-OH group which produces an enhancement in stability of NH3 adsorption. Charge transfer amount in the NH3 adsorption process is enhanced by C-Co coupling effect, C atoms from graphene, lattice oxygen from Co3O4 and pre-adsorbed O-2 or H2O. This work gives a better understand of influence factors of NH3 adsorption on Co3O4/graphene composite which is important for its catalytic reaction. It provides a theoretical basis for controlling catalytic reaction in NH3 treatment or sensing process.