Hexagonal boron nitride with nanoslits as a membrane for water desalination: A molecular dynamics investigation

In this work, we investigate how nanoporous hexagonal boron nitride (hBN) membrane can achieve efficient water/ion separation using molecular dynamics simulations. In particular, it is interesting to figure out the transport mechanisms through slit-like orifices with different edge patterns, namely armchair, B-edged, and N-edged. It is observed that the water and ion conduction rates are sensitive to the edge patterns, which is attributed to the intriguing electrostatic interactions between hBN and solution particles. The armchair nanoslits barely discriminate ion from water molecules, whereas the nanoslits edged with zigzag patterns collaboratively impede ion permeation and allow fast water conduction. Our simulations not only support that hBN is a promising candidate for the development of permeable membrane for water desalination but also highlight the importance of nanoslit edge pattern. Together, this work will be helpful for the design of permeable membrane in the future.