Study of MXene and Electrolyte Materials for Flexible Supercapacitors

Supercapacitors are promising electrochemical energy-storage devices known for high power density, rapid charge–discharge rates, long cycle life, and good mechanical flexibility. Their performance depends strongly on the properties of electrode and electrolyte materials, as well as factors such as ion transport and operating voltage. In recent years, two-dimensional materials, particularly MXenes, have gained significant attention for flexible supercapacitor applications. Ti₃C₂Tₓ MXene offers high electrical conductivity, hydrophilic surfaces, layered structure, and favourable electrochemical properties, making it a suitable electrode material. Graphene and other carbon-based materials can further enhance conductivity and structural stability when combined with MXene. This review examines the role of MXene-based electrodes and different electrolyte systems in improving capacitance, energy density, power density, and cycling stability. It also discusses major challenges, including MXene restacking, oxidation, limited ion accessibility, and the development of flexible gel and solid-state electrolytes. The combination of MXene electrodes with suitable electrolytes provides considerable potential for lightweight, flexible, and efficient energy-storage devices.