▎ 摘　　要

NOVELTY - A composite material comprises beta -manganese dioxide nano-wires growing uniformly and vertically on graphene nanosheet. The nano-wires are elongated sheet nano-wires. USE - Composite material for super capacitor (claimed). ADVANTAGE - The composite material has high manganese dioxide faraday capacitance and excellent graphene conductivity, and improves the electrochemical performance of the composite material. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of composite material, which involves (1)dissolving sodium dodecylbenzenesulfonate (SDBS) and Polyvinylpyrrolidone (PVP, preferably 10000) in deionized water under magnetic stirring condition until completely dissolved, and recording as solution 1,dripping amount of manganese nitrate of 50% and potassium permaganate of 0.2 mol/L in continuous stirring for 30 minutes to obtain mixed solution 2,transferring mixed liquid into hydrothermal kettle, and treating at 180 degrees C for 4 hours, cooling to room temperature, washing with de-ionized water for several times and remove sodium dodecylbenzenesulfonate (SDBS) and polyvinylpyrrolidone (PVP), using water with ethanol to remove remaining water and drying to obtain manganite precursor powder, weighing above manganite dispersing uniformly in sodium hydroxide (preferably at a concentration of 2 mol/L) to obtain solution (3), transferring the solution (3) to hydrothermal kettle, cooling to room temperature, washing with absolute ethanol to remove residual water, drying, and calcining at 300 degrees C for 2 hours to obtain beta -manganese dioxide nanowire powder. The mass ratio of sodium dodecylbenzenesulfonate (SDBS), Quality of polyvinylpyrrolidone (PVP, 10000), manganese nitrate, and potassium permaganent is (1.5-2):(0.7-1.2):(0.3-0.8):(0.2-0.7), and 0.5-5 mass% sodium dodecylbenzenesulfonate (SDBS) in solution 1, amount of manganite precursor powder and sodium hydroxide solution is 10-20 ml, and sodium hydroxide solution per 10 mg manganite precursor powder, (2)using graphite, sodium nitrate, potassium permanganate, concentrated sulfuric acid, hydrogen peroxide, and hydrochloric acid as raw material graphite oxide was prepared by improved hummers method, and obtaining by ultrasonic treatment, dispersing beta -manganese dioxide nano-wires in above preparation, stirring graphene oxide for 4-8 hours, mixing solution is ultrasonically processing for 1-2 hours. The mass ratio of beta -manganese dioxide and graphite oxide is (0.5:1)-(2:1), transferring mixed liquid after ultrasonicating process to hydrothermal kettle at 100-150 degrees C for 12 hours to obtain nano-wire-shaped manganese dioxide/graphene hydrogel, and putting obtained hydrogel into freeze drying for 24 hours to obtain nano-wire-shaped manganese dioxide/graphene aerogel composites.