Methane, Chlorofluorocmethane and Chlorodifluoromethane Adsorption onto Graphene and Functionalized Graphene Sheets: Computational Methods

Abstract

Chlorofluorocarbons (CFCs) are among the environmental pollutants that destroy the ozone layer, and it is necessary to explore materials with good ability for adsorption of them. In this study, the structure of armchair graphene (3,3) with a length of 10 Å was optimized using quantum mechanical calculations, and then it was functionalized with hydroxyl and fluorine groups to interact with environmental pollutants such as methane, chlorofluoromethane (R-31) and chlorodifluoromethane (R-22). Adsorption of these substances comprehensively on graphene functionalized with O-H···F groups and virgin graphene from It was investigated through quantum mechanical calculations, molecular dynamics, and Monte Carlo simulations. Energy data, structural parameters, electronic properties, electron charge density, molecular electrostatic potential maps, charge transfer, density of states diagrams, and non-covalent interactions were were analyzed to evaluate adsorption potential. The adsorption sites with the lowest energy value ​​and possible configurations were identified by tracking the Metropolis Monte Carlo probes from the location of the configuration of the absorber-adsorber pairs. Using adsorption isotherms, adsorption energy, binding energies, and isosteric heat values, adsorption effectiveness was considered. The obtained structures showed suitability after the equilibrium and product steps for structural, dynamic, and statistical properties calculations.