Improvement of the hydrogen storage performance of t-graphene-like two-dimensional boron nitride upon selected lithium decoration

In recent years, search for applicable bidimensional (2D) hydrogen storage materials with high capacity and excellent H 2 physisorption properties has attracted considerable attention from scientists and researchers. According to the rational design, and using first-principles calculations, we propose a t-graphene-like boron nitride monolayer (t-B 4 N 4 ) for hydrogen storage application by replacing C atoms in t-graphene with B and N atoms. The thermal stability and polarization mechanisms of lithium atoms adsorbed at the center of octagons on the t-B 4 N 4 system were evaluated at 300 K using ab initio molecular dynamics (AIMD) calculations. Moreover, Li-decorated double-sided t-B 4 N 4 can store up to 32H 2 molecules with an average hydrogen adsorption energy of 0.217 eV per H 2 and a maximum hydrogen storage capacity of 12.47 wt%. The reversibility of adsorbed hydrogen was checked and the calculated desorption temperature was 161 K, much higher than the critical point for hydrogen. Based on diffusion barriers, the H 2 molecule diffusion kinetics is faster on the t-B 4 N 4 surface than that on t-graphene and graphene. Lithium decoration enhances the hydrogen storage capacities, reversibility and diffusion kinetics of t-boron nitride monolayer.