Doping of graphene-based materials with heteroatoms relies on the disruption of existing charge densities found on pristine graphene. Even though it is known that this phenomenon helps catalyze oxygen reduction reaction (ORR), there are only a few theoretical studies regarding the use of halogen as dopants despite their high electronegativity differences with carbon. Using density functional theory calculations, this work explores the low-concentration halogenation of monovacant graphene as well as the adsorption of oxygen atom onto resulting halogen-based substrates (X = F, Cl, Br, I). In general, formation of doped graphene and the subsequent adsorption of monatomic oxygen is more favored in non-coplanar systems than in their coplanar counterparts. In addition, F-based systems exhibited the most favorable energetics for monoatomic adsorption and electronic properties among the four substrates. Electronegativity also plays a key role on the destruction and formation of molecular structures during the adsorption of monatomic oxygen. Further work with adsorption of O2 on these substrates is warranted to elucidate their potential to catalyze ORR.
- Density functional theory
- Halogen adsorption
- Halogenated monovacant graphene
- Oxygen adsorption