▎ 摘　　要

NOVELTY - Complex separation film comprises deposition substrate layer, separation layer and fixed protective layer that are set from bottom to top, where both the deposition substrate layer and the fixed protective layer are porous carrier materials with micro-pores, the separation layer adopts a porous two-dimensional material with nano-pores and has thickness of 0.3-50 nm and the porous two-dimensional material is prepared by exfoliating the layered material by using oxide semiconductor nano-powder, where the area of the porous two-dimensional material is larger than the area of the micron holes in the porous carrier material. USE - The complex separation film is useful for separation and purification of nanoparticles, macromolecules, proteins or viruses with different particle sizes (claimed). ADVANTAGE - The complex separation film has small membrane thickness and filtration resistance, hence reduces filtration time and improves filtration efficiency. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for preparing the complex separation film, which involves (a) using oxide semiconductor nano-powder to exfoliate layered materials to prepare porous two-dimensional materials with nano-pores, (b) dispersing the porous two-dimensional material obtained in step (a) in a solvent and stirring evenly to obtain a suspension solution, the suspension solution contains 0.5-30% porous two-dimensional material, (c) suspending and depositing the suspension solution obtained in step (b) on the deposition substrate layer to form a separation layer and (d) covering a fixed protective layer on the separation layer obtained in step (c), volatilizing the solvent and drying to obtain complex separation film..