DFT study of single-walled carbon hollows as media for hydrogen storage

Abstract

Understanding the interaction of hydrogen molecules with hollow materials is crucial in the fields of hydrogen storage, sensors, catalysis, and fuel cells. In this paper, we studied hydrogen adsorption on single-walled carbon hollows by means of DFT-D3 calculations. These structures adsorb H2 molecules significantly stronger (adsorption energy, Ea, of −12.55 to −20.56 kJ/mol) than coronene (−4.15 kJ/mol), the representative of graphene, and corannulene (−7.83 kJ/mol), a slightly bent polyaromatic molecule. The reduced density gradient analysis was involved to visualize interacting regions between hydrogen and a series of adsorbents. Energy decomposition analysis was used to divide the total interaction energy into constituents. It is founded that the dispersion term is dominating in all studied cases. The present results should broaden our understanding of the mechanisms of hydrogen storage using carbon hollows.