文摘
Using first-principles calculations and molecular dynamics simulations, we theoretically explored the potential applications of hexagonal boron nitride (h-BN) for H2/CH4 separation. The h-BN with appropriate pores possesses excellent H2/CH4 selectivity (>105 at room temperature). Furthermore, the adsorption energies (0.1 eV more or less) of both H2 and CH4 on the designed monolayer membranes are sufficiently low to prevent the blocking of the nanopores in a realistic separating process. Particularly, we demonstrate a highly promising membrane (h-BN with a triangular pore and a N9H9 rim) with a calculated diffusion barrier of 0.01 eV for H2 diffusion, and the simulated flux of H2 across the single layer is as large as 4.0 脳 107 GPU at 300 K. Additionally, the estimated permeability of H2 significantly exceeds the industrially accepted standard for gas separation over a broad temperature range. Therefore, our results suggest that porous boron nitride nanosheets will be applicable as new membranes for gas separation.