▎ 摘　　要

NOVELTY - Electrochemical method for preparing large sheet diameter graphene involves under the protection of an inert gas, using a three-electrode system, in the electrolyte, increasing the potential from the lowest potential of ion intercalation to the highest potential of ion intercalation to prepare graphite interlayer compounds, performing the constant potential electrolysis under the ion decomposition potential, and peeling-off the graphite intercalation compound to obtain graphene with a large sheet diameter. USE - Electrochemical method is used for preparing large sheet diameter graphene used in metal oxide semiconductor (MOS) device such as sensor, photo-catalyst and flexible electronic device. ADVANTAGE - The method provides large-diameter graphene with high quality. The graphene sheet diameter prepared by the method can reach the order of 10 ??m, and the oxidation degree is low, defect is small, and it can be applied to MOS device. The method uses electrochemical two-step method to graphene, in the electrolysis process, negative electrode graphite will generate reduction reaction, inhibiting the generation of oxygen-containing functional group on the surface of the graphite, improving the C/O of the product graphene, reducing the defect of the graphene, after the first step of electrolysis to obtain graphite interlayer compound, then performing constant potential electrolysis under the ion decomposition potential, decomposing the ion embedded between graphite layer and the co-embedded solvent molecule, when the particle is decomposed