Comprehensive insights into metal–organic frameworks: Synthesis strategies, structural diversities, and applications in next-generation supercapacitors

Metal–organic frameworks (MOFs) are crystalline porous materials created through the coordination of metal centers with organic linkers. Because of their adjustable structures, high surface areas, and versatile chemistry, they have garnered considerable interest as potential candidates for next-generation energy storage technologies. Due to their exceptional surface area, tunable pore structures, and functional modifiability, MOFs have shown remarkable promise in electrochemical devices, particularly supercapacitors. This survey offers a detailed analysis of the physicochemical properties, preparation methods, and classification of MOFs, emphasizing their role as electroactive materials. The effectiveness, scalability, and environmental sustainability of many manufacturing approaches, such as solvothermal, microwave-assisted, electrochemical, and mechanochemical synthesis, are rigorously evaluated. The article also discusses in situ methods used to investigate ion transport and electrochemical behavior, as well as the microscopic processes of charge storage, including electric double-layer capacitance (EDLC) and pseudo-capacitance. The electrochemical performance of single-metal and mixed-metal MOFs, particularly frameworks based on cobalt and nickel, as well as their potential for synergy in hybrid structures, is given special consideration. Lastly, issues with conductivity, stability, and environmental effect are covered, along with current green synthesis trends and potential future directions for high-performance MOF-based supercapacitor design.