▎ 摘　　要

NOVELTY - A graphene separation film comprises a support layer and a separation layer. The separation layer is a double-layer graphene film with nanopores. USE - Graphene separation film used in total organic carbon analyzer (claimed) for testing and monitoring of purity of drinking water and process water in manufacture and processing of electronic component, semiconductor chip, biomedicine product and fine chemicals. ADVANTAGE - The graphene separation film is economical and hard to damage, and utilizes double-layer chemical vapor deposition (CVD) graphene film as separation layer material of composite film, which improves the single-layer CVD graphene film application in the separation film, and plasma etching method to introduce high-density ordered nanopores into the double layer graphene film prepared by the laminated transfer method, which ensures the selectivity and permeability of the graphene separation film. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of the graphene separation film, which involves (s1) forming the support layer on the surface of the single-layer graphene grown on the substrate, (s2) attaching an additive transfer medium on the supporting layer to obtain an additive transfer medium/support layer/single-layer graphene/substrate composite layer, removing the substrate and releasing the additive transfer medium to obtain a support layer/single-layer graphene composite layer, (s3) attaching the support layer/single-layer graphene composite layer to the single-layer graphene surface formed on the substrate to form a support layer/double-layer graphene/substrate composite layer, attaching an additive transfer medium on the support layer of the support layer/double-layer graphene and removing the substrate and releasing the additive transfer medium to obtain a supporting layer/double-layer graphene, and (s4) making pores in the support layer/double-layer graphene composite film, and forming nanopores on the double-layer graphene.