MOF-Based Nanocomposites for Energy Storage and Supercapacitor Applications

Abstract

The environmental issues brought on by the extensive usage of unsustainable energy sources like coal or petroleum have made energy storage devices one of the hottest topics in recent years. Especially for electrical energy, capacitors are a typical energy storage technology. Numerous varieties have been suggested, including electrolytic capacitors, mica capacitors, paper capacitors, ceramic capacitors, film capacitors, and non-polarized capacitors. Depending on their inherent characteristics, they have different applications. Dielectric capacitors can store a respectable amount of energy, but current research focuses on increasing that energy density and making the materials lighter and more flexible. A threat to living standards, societal security, the economy, and even the environment is posed by the energy crisis due to growing global oil prices and global warming. To achieve our ultimate goal of sustainable and clean energy production, transit, storage, and end use, advanced functional materials, particularly polymer nanocomposites, have started to play an unprecedented role. Over the past ten years, numerous advancements and successes in polymer nanocomposites have been documented; nevertheless, functional polymer nanocomposites for energy storage and conversion have not yet received much attention. Metal-organic frameworks (MOFs) comprise metal ions/clusters and organic ligands which are very porous materials. They are effective in storing clean energy, especially hydrogen gas, because of their huge surface area and tunable pore size. Over time, doping with either noble metals or nanoparticles has led to the development of synthetic MOF techniques. To improve MOFs' effectiveness as an energy storage device, they are also used in polymers, carbons, ionic liquids, as well as solid inorganic compounds. In comparison to other forms of carbon, MOF-derived carbon compounds are easier to mix with other materials, have a lower density, and more exposed active sites. The hollow internal cavity where the active components load and unclog the diffusion channel serves as the foundation for the composite's overall stability. In addition to having strong electrical conductivity and stability, carbon compounds generated from MOFs also successfully keep their porosity while gaining a significant amount of surface area from MOF precursors. To provide the ideal material for energy purposes, these materials may also have their structure and size altered by deliberate synthetic control. MOFs have a bright future in the context of energy conversion and storage. To create porous carbons or metal oxide electrodes with specific morphologies and compositions, MOFs can be employed as supercapacitor electrodes or as precursors/templates. Supercapacitors' activity and stability are significantly increased by their particular porous architectures and the extremely active characteristics of their MOFs-based electrodes. Future research must, however, address many issues, including the stability and conductivity of MOFs, the inadequate capacitance of NPCs generated from MOFs, and the poor specific surface area of metal oxides derived from MOFs. The chapter makes the case that more work and attention must be put forth if MOFs and their derivatives are to be used in high-performance supercapacitors.