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It was found the physical adsorption could be an efficient strategy for high capacity, high efficiency and high safety in hydrogen storage. In this research, a systematic investigation into the potential of the B 2 N monolayer as an excellent physical adsorption hydrogen storage material is conducted by utilizing the first-principles calculation method. The findings of the investigation demonstrate that the B 2 N monolayer has a planar lattice and excellent structural stability. It is possible for H 2 molecules to adsorb onto the B 2 N monolayer spontaneously. Both the individual adsorption and saturation adsorption corresponded to average adsorption energies ranging from -0.221 to -0.194 eV, fulfilling the physical adsorption criteria. In the case of saturation adsorption, a 1 × 2 × 1 B 2 N supercell can store a total of 24 H 2 molecules, with the hydrogen gravimetric density up to 14.511 wt% and volumetric density up to 138 g L -1 . A semi-empirical calculation method is used to research the performance of the system in terms of adsorption and desorption with actual temperature and pressure conditions. Under the actual conditions with adsorption carried out at 30 atm/233 K and desorption carried out at 3 atm/358 K, the maximal reversible hydrogen storage capacity of the hydrogen storage system based on the B 2 N monolayer can still reach 12.157 wt%, which is superior to that of many other boron-nitrogen compounds and metal-free functionalized hydrogen storage materials. The findings of this work indicate that the pristine B 2 N monolayer is one of the promising physical adsorption materials which could achieve excellent reversible hydrogen storage under defined conditions.

Searching for good anchoring materials that can suppress the shuttle effect is critical to large-scale commercialization of lithium-sulfur (Li-S) batteries. In this work, the adsorption behavior of lithium polysulfides (LiPSs, such as S 8 and Li 2 S n , n = 1, 2, 4, 6, and 8), the sulfur reduction reaction (SRR), the decomposition processes of Li 2 S and the diffusion behavior of Li atoms on intrinsic and doped 2D biphenylene (BIP) are systematically investigated by employing the first-principles calculation method. Calculations show that the adsorption energies of LiPSs on the electrolyte (DOL and DME) are smaller than those on the intrinsic/B doped BIP. The moderate anchoring strength (0.8-2.0 eV) between LiPSs and the BIP can effectively suppress the shuttle effect. Moreover, the Gibbs free energy barrier for SRR is 0.72/0.64 eV on intrinsic/B doped BIP. The dissociation energy barrier of Li 2 S on intrinsic/B doped BIP is 1.35 eV, while the diffusion energy barrier of Li atoms on intrinsic/B doped BIP is 0.18 eV/0.30 eV. Lower energy barriers are conducive to enhancing the discharging and charging efficiency. Therefore, intrinsic and B doped BIP are predicted as good anchoring materials for Li-S batteries.