First-principles study of SF6 decomposed gas adsorbed on Au-decorated graphene

- We theoretically investigated the decomposed gaseous components of sulfur hexafluoride (SF6), namely, H2S, SO2, SOF2, and SO2F2, adsorbed on pristine and Au-embedded graphene based on DFT-D, in which the van der Waals effect is considered.
- H2S, SO2, SOF2, and SO2F2 are chemisorption on Au-doped graphene, appreciably stronger than physisorption on pristine graphene in which the van der Waals dominates.
- Only H2S exhibits n-type doping to Au-graphene, whereas the rest gases exhibit p-type doping. The n-type and p-type sensing behaviors that Au-doped graphene displays to different gases play a crucial role in selective sensing application.
- Magnetic moments fluctuate substantially in the original Au-graphene when H2S and SO2 are adsorbed. While the adsorption effects of SOF2 and SO2F2 generate magnetism quenching. The different changes of magnetic moments in every adsorption system provide another approach to selective detection.
- The charge transfer mechanism is deeply discussed in this paper.