▎ 摘　　要

We employed density functional theory to characterise H2S adsorption, and dissociation on the pristine and Stone-Wales (SW) defected BC3 graphenes. H2S is predicted to be weakly adsorbed on the pristine graphene with the adsorption energy of about 7.11 kcal/mol. Two types of SW defects were generated by rotating a C-C bond (SW-CC) or a B-C bond (SW-BC) by about 90 degrees. We predict that, in contrast to SW-BC, dehydrogenation of H2S is energetically more favourable on the SW-CC compared to the associative adsorption. It is also found that SW-CC formation is more favourable than the formation of SW-BC. Molecular adsorption of H2S on both of the SW defected sheets is more favourable than that on the pristine sheet. The preferable adsorption process on the SW-BC and SW-CC defected graphene sheets is via associative and dissociative mechanisms, respectively. Furthermore, the highest occupied molecular orbital and lowest unoccupied molecular orbital energy gap of the SW-BC defected sheet is highly sensitive to the adsorption process which may be used for the detection of H2S.