Simulation of the effect of electric field on the performance of ion separation and water desalination using a graphene-carbon nanotube membrane

Using molecular dynamics (MD) simulations, a graphene-carbon nanotube membrane is exposed to external electric field with intensities E = 0.1, 1, 10, and 100 mV/Å in order to separate Na⁺ and Cl^- ions from a salt water solution to produce fresh water. The results show that by increasing the strength of the applied electric field, the ion separation will be increased to 100% for E = 100 mV/Å. It is found that the ion separation efficiency of this filter is already greater than 90% for E = 10 mV/Å. Based on the results of this study, it is suggested that the graphene-carbon nanotube membrane can be used as a device of water desalination under the application of electric field.