▎ 摘　　要

NOVELTY - Preparation of composite material having sea urchin-like structure, involves: 1) preparing dispersion liquid using improved Hummers method, concentration of graphene oxide in dispersion liquid is 1-2 mg/ml; 2) performing 125-200 watts power ultrasonic treatment on dispersion liquid for 10-30 minutes, removing dispersion liquid and adding strong acid to adjust pH to 1-2; 3) preparing MXene aqueous dispersion by selectively etching MAX phase powder using hydrofluoric acid; 4) mixing dispersions formed in steps 2 and 3, such that weight ratio of graphene oxide and MXene is 10:1-20:1, performing ultrasonic dispersion on mixed solution for 15-30 minutes in 180-200 watts power ice bath, performing hydrothermal reaction on mixed solution at 140-160degrees Celsius for 3-4 hours, removing, filtering and washing with deionized water until filtered water is neutral; 5) drying mixture at 50-80degrees Celsius for 4-10 hours, freezing for 12 hours and freeze-drying for 24-32 hours. USE - The composite material prepared is used in the fields of biomedicine, catalysis, extraction separation, batteries or supercapacitors. ADVANTAGE - The composite material prepared, has excellent hydrophilic property due to the unique surface micro-nano structure. The material has water contact angle 17.5 +/-2 degrees, and has ability to absorb moisture in air and keep the structure stable. In the composite material, the graphene oxide layer has higher specific surface area and more active sites due to the unique structure. The method provides a flexible and controllable platform for the preparation of graphene-based and MXenes-based composite materials. DESCRIPTION OF DRAWING(S) - The drawing shows an SEM image of the surface structure of the graphene oxide/MXene composite material.