Estimation of graphene surface stability against the adsorption of environmental and technological chemical agents

The ability of graphene to resist the chemical transformations caused by chemisorption of several environmental and technological chemical agents (H₂, O₂, H₂O, H₂O₂) was studied using DFT ab initio calculations of potential energy surfaces of adsorption on perfect and defect (single vacancy and Stone–Wales defect) graphene with zero and finite curvature. Beside the evident result that structural imperfections such as curvature and atomic defects make graphene chemically vulnerable, it was found that the two kinds of impact of vacancies and Stone–Wales defects on the chemical stability of a sp²-hybridized carbon lattice are essentially different. In the latter case, chemisorption barriers for any kind of chemical agents decrease with increasing curvature but, in the case of single vacancies the finite curvature lowers the adsorption probability for oxygen-based molecules. In general, it was shown that single-layered graphene could be used as an effective protecting coating against environmental and technological chemical agents.