The search for novel materials for effective storage and separation of CO2 molecules is a critical issue for eliminating or lowering this harmful greenhouse gas. In this paper, we investigate the potential application of a porphyrin-like porous fullerene (C24N24) as a promising material for CO2 storage and separation using thorough density functional theory calculations. The results show that CO2 is physisorbed on bare C24N24, implying that this material cannot be used for efficient CO2 storage. Coating C24N24 with Ca atoms, on the other hand, can greatly improve the adsorption strength of CO2 molecules due to polarization and charge-transfer effects. Furthermore, the average adsorption energy for each of the maximum 24 absorbed CO2 molecules on the fully decorated Ca6C24N24 fullerene is -0.40 eV, which fulfills the requirement needed for efficient CO2 storage (-0.40 to -0.80 eV). The Ca coated C24N24 fullerene also have a strong potential for CO2 separation from CO2/H2, CO2/CH4, and CO2/N2 mixtures.
