Reversible hydrogen adsorption in Li functionalized [1,1]paracyclophane

Abstract

Hydrogen is a good alternative to replace fossil fuels in automobiles. Storage of hydrogen for vehicular applications with high gravimetric density is a challenging task. The hydrogen sorption capacity of [1,1]paracyclophane functionalized with Li is investigated using density functional theory. Li functionalized [1,1]paracyclophane physisorbs 8 H2 achieving the maximum hydrogen weight percentage up to 13.42 %. All positive vibrational frequencies and a significant difference in the energy of frontier molecular orbitals confirm the stability and high absolute hardness of the host. Molecular dynamics simulations prove the thermal stability and reversibility of hydrogen adsorption over Li functionalized [1,1] paracyclophane implying the ease of on-board reversible hydrogen storage. Our findings confirm that Li decorated [1,1]paracylophane is a good hydrogen storage material meeting the 2020 targets of DOE.