Modulating the electronic structures and sensing properties of metal and non-metal atoms modified graphene sheets

Abstract This study is to explore different graphene supports effect on the stability of metal atoms and their adsorption characters of gas molecules by using the density functional theory (DFT) calculations. Based on the divacancy structure (555-777-) of graphene, three N, Si and P dopants within 555-777-graphene (3NM-graphene) can regulate the stability and activity of supported metal atoms (M = Co and Pt). Among the toxic gases, the 555-777-graphene-M exhibits high sensitivity for the adsorbed NO molecule. Besides, the isolated gas molecule on 3NM-graphene-M sheets is more stable than that on the 555-777-graphene-M sheets. The NO as specific gas molecule can be easily detected due to it has the largest adsorption energy. The NH 3 and SO 2 have larger adsorption energies than that of HCN molecule. Furthermore, the electronic and magnetic properties of gas molecules on 3NM-graphene-M sheets are comparatively investigated. It is found that the orbital hybridization between gas molecule and metal catalyst can well reveal the change in adsorption stability and magnetic properties by the transferred electrons. In comparison, the adsorbed gases on 3N-graphene-Co systems have larger magnetic moments than those on 3P-graphene-Pt and 3Si-graphene-Co sheets. These results can provide important information for designing the novel graphene-based materials as gas sensor devices.