Enhanced physical hydrogen storage in g-C10N3 monolayer with lithium decoration: A first-principles study
Chen Cai, Jing Xiang, Lingyu Ye, Jing Tao, Xihao Chen, Peng Gao, Che Zhang
Abstract
The pure monolayer has low hydrogen gravimetric storage capacity due to the fact that their van der Waals interactions are not strong enough. In this study, we proposed a novel composite, Li ∘ , for physical hydrogen storage based on first-principles calculations. Lithium (Li) atoms can securely anchor to with a bonding energy of -3.37 eV, exhibiting excellent thermal stability. Li ∘ can hold 7 H 2 molecules per unit cell around room temperature, achieving an 8.0 wt% gravimetric storage capacity with average adsorption energies ranging from -0.277 eV/H 2 to -0.208 eV/H 2 . Desorption temperatures range from 269 K to 358 K, indicating good kinetic properties. Relative energy studies confirm Li ∘ as a promising energy storage material under moderate pressure (>6 bar) and room temperature conditions. The adsorption mechanism involves synergistic electrostatic and van der Waals interactions. We hope that more material-based hydrogen storage techniques will be developed in this direction. • Lithium atoms can strongly bond with monolayer. • The Li ∘ was investigated for reversible hydrogen storage. • The hydrogen gravimetric storage capacity of Li ∘ can be as high as 8 wt%.