Molecular hydrogen storage in fullerenes: A dispersion-corrected density functional theory study

H₂ physisorption within curved carbon nanomaterials for potential fuel storage on board vehicles is studied using dispersion-corrected Density Functional Theory. Full C_n (n = 20, 60, 180, 540, 960) fullerenes were considered along with single-walled carbon nanotubes ((3,3), (5,5), (9,9)) and graphene to investigate the effects of curvature, confinement, platinum and non-metal (B, N, O) dopants, C_fullerene–H₂ and H₂H₂ distances, H₂ orientation on C_fullerene–H₂ interactions. The study mainly focuses on H₂ stored within the fullerene with some investigation into external H₂. A significant attractive C_fullerene–H₂ interaction energy of −28 kJ/mol is observed for H₂ in curved carbon nanomaterials where H₂ molecules are located ca. 2.9 Å from carbon atoms in a highly confined system. Dopants have the potential to increase the favourability of C_fullerene–H₂ interactions when multiple H₂ molecules are present by affecting the orientation of H₂ molecules within the carbon nanomaterial. This paper presents analysis of several carbon nanosystems and then proposes possible materials for H₂ storage on board vehicles.