Supercapacitors: Electrolyte materials and MXene based Flexible Supercapacitors

Abstract: Supercapacitors are advantageous over capacitors owing to their high capacitance value. Supercapacitors are durable, show long life expectancy and flexibility. Supercapacitors are preferred over batteries due to high power density . The Capacitance of the supercapacitor can be increased by using various methods like changing the electrolyte material, fluctuating the pH of the electrolyte, broadening the Operating Voltage Window and improving the specific Capacitance.[1] One of the most explored among these is changing of electrolyte material. This review paper deals about how we can increase the capacitance of the supercapacitor by changing the anodic material. MXene and Graphene are the Carbon- based anodic electrolyte materials discussed. MXene has high electrical conductivity, high flexibility and high energy density making it a promising electrode material. The synthesis of MXene can be carried out by HF etching, Fluoride Based Salt Etching and Fluoride free etching. MXene should exhibit many properties like hydrophilicity, malleability, 2D structure and flexibility and this can be achieved by developing flexible electrode material. The structure and design of the electrode material determines the electrical performance of the MXene. Recent research has concentrated on using MXenes and related composites to build SCs on various substrates, such as self-supporting, PET-supported, carbon cloth fiber-supported, and others. For MXene based on self-support the Vacuum Filtration is the method used. Heat treatment and dry freezing are the techniques employed. Composite films can be built by integrating MXene with Graphene and Carbon Nanotubes. This enhances the electrochemical performance of the supercapacitors. Fiber-supported MXenes show great electrical performance. Due to their stable chemical properties, high electrical conductivity, and excellent mechanical abilities, fabric fibres can be used as current collectors for flexible substrates to support or load active components for the production of flexible energy storage systems.