▎ 摘　　要

NOVELTY - Preparing self-supporting MXene composite film involves mixing the electrode material solution with the MXene solution, stirring and sonicating to form a uniform composite material mixed solution. The metal foil is placed into the obtained mixed solution, reduced at room temperature for 0.5-24 hours to form MXene composite film on the surface of the metal foil. The obtained metal foil and the MXene composite film are placed on the surface into an acid solution to peel the MXene composite film from the surface of the metal foil. The MXene composite film obtained by washing the stripped MXene composite film with deionized water to neutrality and drying. USE - Method for preparing self-supporting MXene composite film used in green energy, intelligent power grid and transportation fields. ADVANTAGE - The method produces product which has high conductivity, large specific surface area, strong applicability, excellent performance, wide application prospect in the green energy, porous structure, no agglomerant and no current collector, and exhibits excellent electrochemical performance, in simple manner.