Water desalination using pressure-driven flow in hexagonal boron nitride (h-BN) and charged nanoporous graphene membranes are investigated using molecular dynamics (MD) simulations. Nanoporous h-BN membranes with pore diameters of 10.1 Å, 12.2 Å, and 14.7 Å were selected to compare with the desalination performance of uncharged nanoporous graphene membranes with similar pore diameters. Salt rejection efficiency of uncharged graphene membranes is superior to that of h-BN, and the pressure drop for both materials exhibits the same inverse-cubic dependence on the pore diameter, regardless of the hydrophobic versus hydrophilic nature of graphene and h-BN, respectively. Charged graphene membranes with pore diameters of 15.9 Å, 18.9 Å, and 20.2 Å were also considered, and 15.9 Å pore diameter with total fixed charge of 12e was found to be the optimum setting for single-layer graphene membrane, resulting in 100% and 98% rejection efficiencies for Na⁺ and Cl⁻ ions, respectively. The corresponding pressure drop is 51.8% lower than that obtained with 9.9 Å pore diameter uncharged graphene with 100% salt rejection. To maintain perfect salt removal, 15.9 Å pore diameter charged bilayer graphene membranes with 12e total charge on the first layer, and − 1e on the second one was simulated at different separation distances between the two membranes. The associated pressure drop is 35.7% lower than that obtained in 9.9 Å pore diameter uncharged base-line case. These findings confirm the potential application of using charged bilayer nanoporous graphene membranes in improving the performance of reverse osmosis desalination systems.

使用分子动力学（MD）模拟研究了六方氮化硼（h-BN）和带电纳米多孔石墨烯膜中压力驱动流动的水脱盐。选择孔径为10.1Å，12.2Å和14.7Å的纳米多孔h-BN膜，以与孔径相似的不带电纳米多孔石墨烯膜的脱盐性能进行比较。不带电石墨烯膜的脱盐效率优于h-BN，并且两种材料的压降对孔径的逆立方依赖性都相同，而不论石墨烯和h-BN的疏水性与亲水性如何。还考虑了带孔的石墨烯膜，其孔径分别为15.9Å，18.9Å和20.2Å，孔径为15.9Å，总固定电荷为12 e被认为是对单层石墨烯薄膜的最佳设定，导致的Na 100％和98％截留效率⁺和Cl ^-离子，分别。相应的压降比孔径为9.9的不带电荷的石墨烯具有100％的脱盐率低51.8％。为了保持最佳的除盐效果，孔径为15.9Å的带电双层石墨烯膜在第一层的总电荷为12 e，− 1 e在第二个膜片上模拟了两个膜之间不同的分离距离。与9.9Å孔径不带电的基线情况下相比，相关的压降降低了35.7％。这些发现证实了使用带电双层纳米多孔石墨烯膜在改善反渗透淡化系统性能方面的潜在应用。