Reversible CO 2 storage and efficient separation using Ca decorated porphyrin-like porous C 24 N 24 fullerene: a DFT study

The search for novel materials for effective storage and separation of CO 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 (C N ) as a promising material for CO storage and separation using thorough density functional theory calculations. The results show that CO is physisorbed on bare C N , implying that this material cannot be used for efficient CO storage. Coating C N with Ca atoms, on the other hand, can greatly improve the adsorption strength of CO molecules due to polarization and charge-transfer effects. Furthermore, the average adsorption energy for each of the maximum 24 absorbed CO molecules on the fully decorated Ca C N fullerene is -0.40 eV, which fulfills the requirement needed for efficient CO storage (-0.40 to -0.80 eV). The Ca coated C N fullerene also have a strong potential for CO separation from CO /H , CO /CH , and CO /N mixtures.