Li decorated graphene like MgN₄ monolayer for hydrogen storage: A first-principles approach

The rapid advancement of hydrogen storage materials possessing high storage capacity, long life-cycle, reversibility, and rapid kinetics is a trending issue. Metal decoration of a two-dimensional material is a successful method of enhancing hydrogen storage capacity. Li-decorated 2D MgN₄ has been inspected as a hydrogen storage material for practical applications employing density functional theory simulations. Our findings indicate that the substrate (LiMgN₄) may adsorb up to 6 molecules of H₂ with a gravimetric storage capacity of 1.83 wt.%, making it a viable choice for storage medium. With an average adsorption energy of 0.21 eV per H₂, hydrogen is effectively sensed by Li-augmented MgN₄ monolayer. Additionally, two-sided Li-decoration is discussed with 12 H₂ adsorbed on each side with a storage capacity of 6.86 wt.% with an average adsorption energy of 0.15 eV/H₂. High desorption temperature confirms the effective desorption of H₂ from the substrate. The Li-decorated porous MgN₄ responds effectively in the adsorbate (H₂) environment. The predicted adsorption energy, recovery time and desorption temperature demonstrate that LiMgN₄ is an exceptional choice for energy storage devices.