Carbon aerogels and xerogels: next-generation materials for sustainable energy and environmental solutions

Carbon aerogels and xerogels, with their 3D porous architectures, ultralow density, high surface area, and excellent conductivity, have emerged as multifunctional materials for energy and environmental applications. This review highlights recent advances in the synthesis of these materials via polymerisation, drying, and carbonisation, as well as the role of novel precursors such as graphene, carbon nanotubes, and biomass. Emphasis is also placed on doped and metal-decorated carbon gels as efficient electrocatalysts for oxygen reduction reactions, enabling four- and two-electron pathways for energy conversion and the production of green H₂O₂, respectively. Aerogels' high specific capacitance and stability also position them as promising materials for supercapacitors. The versatility of carbon aerogels and xerogels offers exciting prospects for future innovations in catalysis, energy storage, and sustainable technologies.