TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The high temperature reaction furnace is a vacuum sintering furnace and/or a calcining furnace. The vacuum sintering furnace and/or a calcining furnace comprise a self-discharge plasma sintering furnace, a resistor heating vacuum sintering furnace, induction heating vacuum sintering furnace, microwave heating vacuum and calciner, preferably self-discharge plasma sintering furnace and/or calciner.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The inert gas is nitrogen, helium, neon, argon, krypton, xenon and radon gas or combination of at least 2, preferably nitrogen and/or argon with a purity of 99.999%. The atomic ratio of carbon element and oxygen element of the graphene is greater than 9, preferably 9-90 or 9-50. The electron mobility of graphene is 800-1200 cm2/V.S, and the conductivity is 200-500 S/m. Preferred Method: The graphene oxide is taken from the group consisting of graphite product obtained by oxidation and stripping method, where the oxidation method comprise Brodie method, Hummers method or Staudenmaier method, and the stripping method comprise pyrolysis expansion or ultrasonic dispersion. The method comprises filling inert gas to achieve inert atmosphere, where the inert gas does not react with graphene oxide and graphene. The method comprises passing the high voltage pressure through inert gas. The high pressure is 1-100 MPa, preferably 10-40 MPa. The high temperature is 900-2000 degrees C, preferably 1100-1500 degrees C. The method comprises performing high pressure reduction treatment for greater than or equal to 1 minute, preferably 2-10 minutes. The method further comprises: (i) placing the graphene oxide powder in a high temperature reaction furnace, sealing and vacuumizing; (ii) introducing inert gas into the high temperature reaction furnace, pressurizing, heating to a predetermined pressure and temperature for reaction; and (iii) naturally cooling to room temperature to obtain graphene.