Strain induced lithium functionalized graphane as a high capacity hydrogen storage material

TL;DR

This study uses first-principles calculations to show that applying strain to lithium-doped graphane enhances its stability and hydrogen storage capacity, reaching up to 12.12 wt%.

Contribution

It demonstrates that strain engineering can significantly improve hydrogen storage properties of lithium-functionalized graphane.

Findings

Li remains stable on graphane under 10% tensile strain.

Binding energy of Li increases by 52% under biaxial asymmetric strain.

Hydrogen gravimetric density reaches 12.12 wt% with 25% Li doping.

Abstract

Strain effects on the stability, electronic structure, and hydrogen storage capacity of lithium-doped graphane (CHLi) have been investigated by stateof-the art first principle density functional theory (DFT). Molecular dynamics MD) simulations have confirmed the stability of Li on graphane sheet when it is subject to 10% of tensile strain. Under biaxial asymmetric strain, the binding energy of Li of graphane (CH) sheet increases by 52% with respect to its bulk's cohesive energy. With 25% doping concentration of Li on CH sheet,the gravimetric density of hydrogen storage is found to reach up to 12.12wt%. The adsorption energies of H2 are found to be within the range of practical H2 storage applications.