▎ 摘　　要

NOVELTY - The method involves providing the stacked arrangement of layers of the graphene-based material. The layers of the graphene-based material define one or more nanochannels between neighboring layers. The electrical charge is varied on a surface of the layers of the graphene-based material. One or more nanochannels are defined to control the size selectivity and/or ionic selectivity of the graphene-based membrane. USE - Method of preparing graphene-based membrane. ADVANTAGE - The parameters result in the better and more energy efficient filtration or desalination membrane. The anion/cation selectivity and selectivity based on ionic valence is increased, by increasing magnitude of the surface charge. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a graphene-based membrane; and (2) a method of separating ions from a fluid stream. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the method of preparing graphene-based membrane.