Enhancement Strategies for Mechanical Robustness of Carbon Aerogels and Their Applications

As a newly emerging light porous material, carbon aerogels are a class of carbonaceous solid materials with high porosity, low density and excellent environmental stability. With the combination of high elasticity, high energy absorption, as well as special properties such as shock absorption, sound absorption and electromagnetic shielding, carbon aerogels are both functional and structural, and widely applied in the fields of flexible sensors, energy equipment, acoustic equipment and environmental protection. However, the existing general conflicts between the mechanical robustness and the intrinsic sparse network in porous aerogel materials have been a common challenge faced by researchers in fields of material science, solid mechanics, design, application and so on. Good robustness could ensure the structural integrity and performance stability of aerogels in the application process, while the sparse network is the prerequisite to ensure the lightweight and porous structure of aerogels. Here, the recent enhancement strategies for the mechanical robustness, including cell-wall strengthening, cell-wall orientation, pore topology controlling and joint reinforcement, were discussed. Specially, the advanced design principles to realize the tensile elasticity in ultra-light all-carbon aerogels without intrinsic stretchable elastomers, were summarized. In addition, the recent applications of robust carbon aerogels were reviewed and the problems to be solved in this field were listed.