Lithium-Decorated Porous BC2P Monolayer: A Novel High-Capacity Material for Efficient and Reversible Hydrogen Molecule Storage

Abstract

The hydrogen storage capabilities of pristine and lithium-decorated porous BC2P monolayers were examined using density functional theory calculations. Findings show that the pristine BC2P has a limited ability to store hydrogen molecules, as it displays a weak tendency for hydrogen adsorption. Lithium atoms can be placed on the eight-membered ring of BC2P, with an adsorption energy of -2.75 eV/Li. This significant adsorption energy, coupled with the high diffusion barriers of the Li atoms, suggests that they do not aggregate on the BC2P surface. The electric field generated by charge rearrangement in Li-decorated BC2P greatly improves hydrogen storage, allowing for the accommodation of up to three H2 molecules per Li atom, with an average adsorption energy ranging from -0.20 to -0.28 eV. This yields a hydrogen storage capacity of 7.68 %wt. Additional calculations of occupation numbers and ab initio molecular dynamics simulations support the idea that hydrogen molecules stored can be released from the Li-decorated BC2P at moderate temperatures and pressures. Therefore, the Li-decorated porous BC2P monolayer is proposed as an innovative and promising material for reversible hydrogen storage applications in commercial settings.