▎ 摘　　要

NOVELTY - Preparing ferroferric oxide/nitrogen doped graphene composite material comprises e.g. preparing 3 mg/ml graphene oxide (GO) dispersion by Hummers method, ultrasonically dispersing, adding cyanamide as nitrogen source and graphene oxide into solution in a mass ratio of 10-20:1, adding distilled water, adjusting pH of solution to 10-12, heating, magnetically stirring, transferring solution into PTFE reactor and insulating, mixing soluble iron acetate and graphene oxide dispersion in a mass ratio of 1:40-60, stirring for 1 hour to obtain stable brown suspension and then sealing brown suspension. USE - The material is useful as cathode electrode material of lithium ion battery (claimed). ADVANTAGE - The material: has certain 3D structure configuration, high specific area, excellent three-dimensional pore structure and operation stability. DETAILED DESCRIPTION - Preparing ferroferric oxide/nitrogen doped graphene composite material comprises (i) preparing 3 mg/ml graphene oxide (GO) dispersion by Hummers method, ultrasonically dispersing, adding cyanamide as nitrogen source and graphene oxide into solution in a mass ratio of 10-20:1, adding distilled water, adjusting pH of solution to 10-12, heating, magnetically stirring, transferring solution into PTFE reactor and insulating, (ii) mixing soluble iron acetate and graphene oxide dispersion in a mass ratio of 1:40-60, stirring for 1 hour to obtain stable brown suspension, sealing brown suspension in a Teflon reactor, carrying out hydrothermal reaction at 160-200 degrees C for 12 hours, hydrolyzing iron acetate into FeOOH and anchored on the surface of 3D graphene to obtain FeOOH/GO intermediate composites, and (iii) filtering resulting FeOOH/GO intermediate composite material, washing, placing in a tube furnace under nitrogen atmosphere, calcining at 500-700 degrees C for 2 hours, self-assembling phase transformation of iron oxide (FeOOH) precursor particles into iron oxide particles, carrying out reduction reaction of graphene oxide to graphene oxide (rGO) in one step to obtain final product. An INDEPENDENT CLAIM is also included for ferroferric oxide/nitrogen doped graphene composite material obtained by above mentioned method.