▎ 摘　　要

NOVELTY - A MXene nanoflower comprises nanoflower that is uniformly distributed on graphene nanosheet. The size and shape of nanoflower are controllable. The nanoflower material can solve problem of layered self-stacking, improves specific surface area, ion conductivity and charge transfer rate, and contains rich oxygen vacancy. The nanoflower attached on small layer graphene sheet layer can enhance material stability and increase electrochemical performance. USE - The MXene nanoflower is used as electrode material of supercapacitor (claimed). ADVANTAGE - The MXene nanoflower structure improves specific surface area of material and contains rich oxygen vacancy, and improves ion conductivity, charge transfer rate and electrochemical performance. The product has very high specific surface area, and displays very high specific capacitance and good cycle stability when used as electrode material of supercapacitor. The method has strong controllability and realizes preparation of large scale uniformity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a method for preparing MXene nanoflower comprising using space-time shaping femtosecond laser and preparing from four dimensions comprising time dimension and three-dimensional space; (2) placing Mxene target in liquid and irradiating by shaping laser; and (3) a method for preparing supercapacitor by MXene nanoflower comprising placing Mxene in graphene oxide dispersion liquid, shaping laser irradiating, generating MXene nanoflower, reducing graphene oxide into layers of graphene, adsorbing MXene nanoflower on graphene sheet layer with layers in bubble generated by shaping laser and uniform flow of liquid phase environment provided by charging device to obtain MXene nanoflower composite material, spin coating on conductive substrate, coating a layer of electrolyte. During irradiation, aeration device is used in combination with bubbles generated by laser to provide liquid bubble environment.