Hydrogen storage capacity of low-lying isomer of C24 functionalized with Ti

Abstract

Hydrogen energy is a sustainable and eco-friendly substitute for reducing fossil fuel dependency and boost the air quality index. High-density reversible hydrogen storage as a vehicular fuel is the biggest challenge. Hydrogen storage capacity in Jahn-Teller distorted C24 fullerene functionalized with Ti is studied by using density functional theory. It is found that Ti atoms form two hexagonal pyramidal clusters due to high cohesive energy. Four hydrogen molecules are adsorbed by each Ti through Kubas interaction with adsorption energies in the range of 0.33e0.76 eV/H2. Our findings of practical hydrogen storage capacity and the van ‘t Hoff desorption temperature reveal that hydrogen molecules are reversibly stored under operable thermodynamic conditions with 10.5 hydrogen weight %. Storage parameters meet the US Department of Energy targets making it a prospective hydrogen storage material.