Novel electrodes for supercapacitor: Conducting polymers, metal oxides, chalcogenides, carbides, nitrides, MXenes, and their composites with graphene

The recent electronic appliances and hybrid vehicles need a high energy density supercapacitor that can deliver a burst and a quick power supply. The high energy density supercapacitor can be obtained by designing proper electrode materials along with appropriate electrolytes. This review begins with different mechanisms of energy storage, giving a brief idea regarding how to design and develop different materials to achieve proper electrodes in the pursuit of high-energy density supercapacitor without compromising its stability. This review later focuses on the engineering of different electrode materials like conducting polymer, metal oxides, chalcogenides, carbides, nitrides, and MXenes. Lastly, the hybrid electrodes made up from composites between graphene and other novel materials were investigated. The hybrid electrodes have high chemical stability, long cycle life, good electronic properties, and efficient ionic transportation at the electrode-electrolyte interface, showing great potential for commercial usage.