Graphene and its derivatives in supercapacitors: a comparative review

Abstract

Recent advancements in supercapacitor technology have garnered significant attention due to their possible applications in next-generation energy-storage systems. Among the various factors that influence device performance, the selection or modification of electrode-materials has been a crucial part. In particular, graphene and its derivatives have emerged as leading candidates owing to their high surface-area, higher electrical conductivity, stability and mechanical robustness. This review critically poses the role of structural tuning through doping, selection of electrolytes, and formation of composites with transition metal dichalcogenides (TMDs), and metal oxides (MOs) in graphene-based supercapacitors. These modifications not only enhance electrochemical performance by improving charge transport and ion diffusion but also address limitations including poor energy density and structural degradation. Moreover, the design of hierarchical porous architectures and nanoparticle–graphene composites offer further improvements in specific capacitance and cycling stability. In this review, fundamentals, type, mechanism, formulae, electrode materials, material properties, and electrochemical behaviors are discussed, along with an outlook on existing challenges and future opportunities in optimizing graphene and its derivative for high-performance supercapacitors.