Characterization of graphene-fullerene interactions: Insights from density functional theory

Using density functional theory (DFT) based approaches that utilize appropriate semi-empirical and nonlocal van der Waals corrections, we rigorously examine the interactions between fullerene (C₆₀) molecules and pristine single layer graphene (SLG) sheets as well as SLG containing isolated mono-vacancy, divacancy and Stone-Wales defect-sites respectively. Our results show that chemical bonding between the C₆₀ molecule and SLG at mono-vacancy defect-sites demonstrate predominantly sp³-like hybridization, in contrast to weaker π-π interactions that characterize C₆₀-SLG systems containing divacancies and Stone-Wales defects.