▎ 摘　　要

NOVELTY - A cathode comprises sequentially stacked graphene film, P-type layer and n-type layer, where the P-type layer comprises cuprous iodide, rhenium trioxide or metal-doped oxide miscellaneous materials comprising phthalocyanine-based oxide material, the phthalocyanine-based material is copper phthalocyanine, zinc phthalocyanine, vanadyl phthalocyanine, titanyl phthalocyanine or molybdenum phthalocyanine, the n-type layer is doped with an alkali metal compound and organic material, and the alkali metal compound is lithium carbonate, rubidium carbonate, stacked cesium nitride or cesium carbonate. USE - Cathode for use in an organic electroluminescent device (claimed). ADVANTAGE - The cathode has high electric and electronic injection ability, and can increase lighting efficiency of the device. DETAILED DESCRIPTION - A cathode comprises sequentially stacked graphene film, P-type layer and n-type layer, where the P-type layer comprises cuprous iodide, rhenium trioxide or metal-doped oxide miscellaneous materials comprising 1-10 mass% phthalocyanine-based oxide material, the phthalocyanine-based material is copper phthalocyanine, zinc phthalocyanine, vanadyl phthalocyanine, titanyl phthalocyanine or molybdenum phthalocyanine, the n-type layered material is doped with an alkali metal compound and organic material, the alkali metal compound is lithium carbonate, rubidium carbonate, stacked cesium nitride or cesium carbonate, the organic material is 2-(4-biphenylyl)-5- (4-tert-butyl) phenyl-1,3,4-oxadiazole, 4,7-diphenyl-phenanthroline, 1,3,5-tris(1-phenyl-1H- benzimidazole-2-yl) benzene, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline or 8-hydroxyquinoline. INDEPENDENT CLAIMS are also included for the following: (1) a method for preparing a cathode (2) an organic electroluminescent device (3) a method for manufacturing an organic electroluminescent device.