In recent years, two-dimensional (2D) MXene materials have attracted a great deal of research interests in the field of energy storage, due to their extraordinary physical/chemical properties. The investigation of the 2D Ti3C2Tx is the most prevalent. MAX phase is a kind of ternary nitrides and/or carbide, its chemical formula for Mn+1AXn (n=1~3), M represents the transition metal elements (such as Sc, Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, etc.), X is the carbon and/or nitrogen, A is main IIIA or IVA group elements. According to different n values, the crystal structure of MAX phase includes 3 types. In the MAX phase, the bonds of M?X and M?A are very strong. Therefore, it is impossible to separate the layers by cutting or other mechanical methods. However, because the M?A bond has higher chemical activity than the M?X bond, the single-layer/low-layer MXenes material can be obtained by chemical etching of M?A bond assisted auxiliary method, and the surface terminations are randomly distributed. Surface terminations play an important role in electrochemical performance. Therefore, how to control the type and quantity of surface terminations is an important part in the current research field. The fundamental structure of the MXene phase was introduced and the relationship between phase structure and performance was analyzed in this work. The electrochemical performances of Mxene phase materials improved by ion implantation, heat treatment, surface modification, electrode design and elemental doping were summarized. Meanwhile, in order to further improve the conductivity and cyclic stability of the materials, the application progress of the composites with carbon, oxide and polymer in the field of supercapacitor was briefly introduced. Phase structure, preparation and electrochemical properties of Mxene material were reviewed, the existing problems and future development direction for Mxene phase materials used in supercapacitor fields were pointed out.
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