▎ 摘　　要

NOVELTY - A graphene-based nanocomposite preparation method involves preparing oxidized graphene. X-ray photoelectron spectroscopy test analysis is performed on graphene. Oxidized graphene dispersion liquid is prepared. Precursor solution is prepared. The prepared precursor solution and oxidized graphene dispersion liquid are added and stirred to obtain a mixed solution, and the mixed solution is removed naturally and cooled to obtain a metal oxide/graphene nanocomposites suspension. The suspension is placed in the centrifuge and washed, and the filtrate is placed in a oven and dried. USE - Method for preparing graphene-based nanocomposite that is utilized in energy storage, photocatalysis and sensor. DETAILED DESCRIPTION - A graphene-based nanocomposite preparation method involves preparing oxidized graphene. X-ray photoelectron spectroscopy test analysis is performed on the oxidized graphene by testing and fitting C1s peaks obtained graphene oxide with CC, CO, C=O and C (O)O. The percentage of amount of substance is a, b, c and d, derived graphene oxide material and functional group content of the percentage amount of b+c+d. Oxidized graphene dispersion liquid is prepared by dispersing the 0.1-10 mg/ml graphene oxide in deionized water, at control frequency of 40-60 kHz for 30-300 minutes. Precursor solution is prepared by weighing metal oxide precursor and oxidant precursor dispersed, which is expressed by the equation as given in the specification, in a solvent at control frequency of 10-20 kHz for 30-60min, to a concentration of 0.2-1 mol/l solution of a precursor. The prepared precursor solution and oxidized graphene dispersion liquid are added dropwise and stirred, the solution is placed in an ultrasonic cleaning machine at frequency of 10-20 kHz for 2-3 hours, an alkali solution is utilized to adjust the pH to 2-11, to obtain a mixed solution, and the mixed solution is transferred to a hydrothermal reaction kettle at 100-240 degrees C for 5-30 hours, the mixed solution is removed naturally and cooled to room temperature to obtain a metal oxide/graphene nanocomposites suspension. The metal oxide/graphene nanocomposites suspension is placed in the centrifuge, at a speed of 500-2000 rpm for 5-30 minutes, washed with water and alcohol until the filtrate pH 7, and the filtrate is placed in a vacuum oven at 40-150 degrees C, vacuum dried for 8-15 hours to obtain graphene nanocomposites.