Hydrogen Storage Performance of Doped Hexagonal Boron Nitride Nanosheets with Thin Layers

As predicted by optimistic theoretical calculations, hexagonal boron nitride nanosheets with thin layers and elemental doping are considered promising media for hydrogen storage. To explore its hydrogen storage performance experimentally, a hexagonal boron nitride nanosheets consisting of only 6 atomic layers with 7 at. % O and 3 at. % F functionalization is prepared through a creative two-step synthesis. Moreover, the hydrogen adsorption at 77 and 298 K under different pressures is systematically measured. When operated in 6 MPa conditions, the hydrogen capacity of h-BNNS at 77 K can reach 1.43 wt %, which is almost three times higher than that at 298 K. By combining experimental data with first-principles calculations, the interaction mechanism between h-BNNSs and H₂ molecules is denoted as physical adsorption and the doped atoms can play a role in enhancing the polarization effect and magnifying the binding energy.