Computational study on the ability of functionalized graphene nanosheet for nitrate removal from water

Abstract

Graphene sheets as nanostructured membranes with various functional groups (fluorine or hydrogen atoms) and different pore sizes were studied to separate nitrate anions from water molecules using molecular dynamics simulation method. Three systems with different functionalized graphene membranes were simulated to purified water from contamination. These three functionalized graphenes which two of them had fluorinated graphene pores with various diameters and one of them had hydrogenated graphene pore that its pore size was smaller than one of the fluorinated graphene pores, were located at the middle of the simulation boxes which contained sodium nitrate aqueous solution. Water molecules crossed from all functionalized graphenes but nitrate ions only passed across the fluorinated graphene with large size pore. In addition to the exerted pressures and the sizes of the graphene pores, the type of the functional groups based on their chemical nature had influence on water permeation and ion rejection.