▎ 摘　　要

NOVELTY - The method involves taking graphene oxide powder as raw material. A layer of a graphene film is deposited on a single crystal silicon substrate (S10). A surface of the grapheme film is arranged with a layer of a Zinc oxide film. Zinc salt and hexamethylene tetra-mine are considered as raw materials. Zinc oxide nano needle array composite material is arranged on a silicon substrate (S20). A graphene layer is deposited on a Zinc oxide surface by using electrostatic spray deposition technology. A sandwich structure of graphene/zinc oxide/graphene composite cathode material is made (S30). USE - Method for preparing field emission composite cathode material of graphene/zinc oxide/graphene sandwich structure. ADVANTAGE - The method enables realizing field emission composite cathode material preparing with strong operability and low processing cost and ensuring mass production to obtain composite cathode material for field emission of graphene/zinc oxide/graphene sandwich structure and emission performance stability. DESCRIPTION OF DRAWING(S) - The drawing shows a flow diagram illustrating a method for preparing field emission composite cathode material of graphene/zinc oxide/graphene sandwich structure. '(Drawing includes non-English language text)' Step for taking graphene oxide powder as raw material, depositing layer of graphene film on single crystal silicon substrate (S10) Step for arranging surface of grapheme film with layer of Zinc oxide film, considering Zinc salt and hexamethylene tetra-mine as raw materials and arranging Zinc oxide Nano needle array composite material on silicon substrate (S20) Step for depositing graphene layer on Zinc oxide surface by using electrostatic spray deposition technology and madding sandwich structure of graphene/zinc oxide/graphene composite cathode material (S30)