▎ 摘　　要

The development of two-dimensional materials with gas-sensitive properties has been a research focus in the field of materials science. Considering the excellent properties of graphene and hexagonal boron nitride, a monolayer composite is put forward and its potential for gas sensing has been investigated by density functional theory. Compared to common gases in the atmosphere and three other toxic gases, sulfur dioxide tends to have a strong mutual effect with this composite. Together with electronic analyses, it is proved that the composite presents excellent sensitivity toward sulfur dioxide molecules and the conductivity can be used as a vital parameter to diagnose the status of gas sensor. What's more, a co-adsorption model demonstrates a favorable performance in high moisture working environment. Thus, we can reasonably draw the conclusion that the presented composite could be an eligible candidate for sulfur dioxide gas detection.