Density functional theory calculations were used to investigate the adsorption behavior of Ca coated B40 fullerene toward CO2 molecules. It was found that Ca atoms are unlikely to form clusters on B40. CO2 molecules can be effectively adsorbed on the Ca coated B40, as evidenced by large negative adsorption energies and significant charge transfer effects. Each Ca atom on B40 may adsorb four CO2, with an average adsorption energy of -0.60 eV which falls within the range proposed for an ideal CO2 adsorbent. Furthermore, Ca coated B40 exhibits high selectivity for CO2 from CO2/N2, CO2/H2, and CO2/CH4 gas mixtures.
