Developing next-generation supercapacitor electrodes by coordination chemistry-based advanced functional carbon nanostructures: Progress, Current challenges and prospects

Owing to their high energy and power density, supercapacitors exhibit great potential as high-performance energy sources for advanced technologies. Efficacious electrode materials with excellent physical, chemical, and morphological properties are significant to developing next-generation high-performance supercapacitors. Carbon materials are promising candidates as electrode materials to industrialize supercapacitor devices. Additionally, high stability, environmental friendliness, natural abundance, good electronic conductivity, nontoxicity, high specific surface area, easy processing, and low cost make them the most significant materials for an electrode. However, low mesoporosity in the carbon-based electrode caused poor electrolyte accessibility. Hence the electrochemical performance is limited in terms of specific capacitance. Extensive research has been carried out to overcome the limitations mentioned above via diverse methods, such as activation, synthesis technique, tuning the carbon surfaces (mechanical strengths, surface area, and surface porosity), and tailoring the carbon materials with highly electroactive materials. To attain higher electrochemical performance of carbon-based electrode materials, the contemporary progress of fabrication of supercapacitor electrode materials comprising different forms of carbon materials tuning with pseudocapacitive materials has been discussed. Furthermore, some prospects and future trends for further improvement in the development of electrode materials for the application to next-generation supercapacitors are discussed.