First-principles study of CO adsorption using metal-doped single vacancy defective graphene

In this study, we investigate the adsorption behavior of CO molecules on pristine graphene, single vacancy defective graphene, and metal-doped single vacancy defective graphene using first-principles calculations based on density functional theory. By comparing the adsorption energy, adsorption distance, charge transfer, charge density differences, band structure, density of states, and work function of CO molecules on different substrates, we demonstrate that single vacancy defective moderately enhance CO adsorption on graphene compared to pristine graphene. Doping single vacancy defective graphene with metal atoms significantly improves the adsorption energy, increases charge transfer, and reduces the adsorption distance between the substrate and CO. Notably, transition metals Mn and Ni exhibit the strongest interaction with CO gas when doped into single vacancy defective graphene, and Mn-SVG and Ni-SVG are suitable for CO detection in controlled environments, which demonstrating their potential as CO gas sensor materials. This study not only offers critical insights for developing CO gas sensor materials but also suggests a novel strategy for designing other polar gas sensors.