Progress in Synthesis of Carbon Aerogels for Advanced Energy Storage Applications

Abstract

Carbon aerogels usually prepared from organic aerogel precursors have many merits such as lightweight, high porosity, large surface area, excellent conductivity, and high temperature resistance for broad applications in the fields of adsorption, catalysis, and energy storage. Particularly, the applications of carbon aerogels in advanced energy storage devices have gained increasing attention in recent years. This paper concludes the preparation and application of carbon aerogels derived from organic precursors. The development of resin- and biomass-derived carbon aerogels for supercapacitors and rechargeable batteries (e.g., Li-ion batteries - LIBs) are highlighted. Furthermore, the development and challenge of carbon aerogel industries are discussed. This work offers a strategic guide to build a close connection between carbon aerogel and energy storage economy. In general, the electrochemical performances mostly rely on the surface structure and chemistry characteristics of carbon aerogels. Carbon aerogels possessing 3D hierarchical porous network structure with appropriate microporosity and mesoporosity, heteroatoms (e.g., N, S) doping, and active metal nanoparticles (e.g., MnO2, Co3O4) loading are key indexes to determine the capacitance capacity, rate capability, and cycle stability of the assembled supercapacitors. Resin derived carbon aerogels have the advantages of large specific surface area and highly tunable pores for supercapacitors, but the poor mechanical properties hinder their application in flexible supercapacitors. In addition, carbon aerogels for the applications of rechargeable batteries are mostly used as the supports for electroactive substances in LIBs and the separators of Li-S and Na-S batteries. Carbon aerogels derived from biomass precursors in comparison with conventional resin precursors have been promising alternatives owing to the benefits of low-cost (abundantly in nature), sustainable, eco-friendly, large specific surface area, tunable pore structure, and strong mechanical properties. The challenges of promoting biomass-derived carbon aerogels into practical use include simplify the procedure and further reduce the time and cost for the preparation of carbon aerogels from diverse biomass precursors.