Carbon gel materials: synthesis, structural design, and emerging applications in energy and environmental technologies

Carbon-based gel materials have become a flexible class of porous materials with great promise for sustainable material innovations, energy storage, and environmental remediation. The synthesis methods, structural categories, and multipurpose uses of carbon gels, such as aerogels, xerogels, cryogels, and hydrogels, are all well covered in this review. These materials are appropriate for a variety of applications due to their special qualities, which include high surface area, hierarchical porosity, electrical conductivity, and mechanical tunability. Recent developments in green synthesis techniques employing precursors generated from biomass are highlighted, including the creation of hybrid systems that combine metal oxides, graphene, and carbon nanotubes to improve mechanical strength, conductivity, and catalytic activity. A critical analysis of how different drying and carbonization methods affect pore structure, stability, and performance is conducted. Carbon gels' uses in fuel cells, lithium-ion/sodium-ion batteries, supercapacitors, and water treatment are discussed, with an emphasis on how their structural characteristics affect their adsorption and electrochemical properties. The analysis also examines the increasing interest in hydrogels based on graphene and gels made from biomass as environmentally friendly and sustainable substitutes for energy systems. Despite impressive advancements, problems with mechanical robustness, pore structure management, and cost-effective large-scale production still exist. In order to create next-generation carbon gel materials for worldwide energy and environmental solutions, future prospects are examined with a focus on combining green chemistry, functionalization methods, and innovative composite designs.