▎ 摘　　要

NOVELTY - Multilayer crosslinked graphene oxide comprises a graphene oxide layer crosslinked by using a crosslinking agent to form a nano-multilayer crosslinked graphene oxide. USE - The crosslinked graphene oxide is useful for preparing reverse osmosis membrane (claimed). ADVANTAGE - The method: has mild conditions; does not require a complicated special ultra-low temperature synthesis equipment; improves the stability of graphene oxide; is environmentally friendly; simultaneously adds multilayer cross-linked graphene oxide as a nano-filler material to the polyamide reverse osmosis membrane, which has excellent salt interception rate and water flux. DETAILED DESCRIPTION - INDEPENDENT CLAIMA are also included for: (1) preparing the multilayer crosslinked graphene oxide, comprising (i) adding a specific amount of a crosslinking agent to the graphene oxide solution to obtain a mixed solution, and filtering the mixed solution by using an ultrafiltration membrane, (ii) placing the ultrafiltration membrane with the cut-off product in an oven, and performing crosslinking reaction at 40-65 degrees C for 1-3 hours, and (iii) removing the cross-linked product from the surface of the ultrafiltration membrane by performing ultrasonication, subjecting the solution obtained after the ultrasonication to dialysis treatment for 24-72 hours, where the dialysis bag has a molecular weight cutoff of 8000-14000 Da; and (2) preparing reverse osmosis membrane by using the crosslinked graphene oxide, comprising adding the crosslinked graphene oxide to an aqueous phase, and performing interfacial polymerization.