Fiber of bioinspired columnar cactus prickle-like structure for reinforced SiC aerogel: Thermal insulation and mechanical properties

The inspiration was obtained from the unique morphology of the columnar cactus prickle-like structure. Biomimetic fiber with a "double network" capability of reflecting heat radiation was prepared by electrospinning and hydrothermal methods. Among them, the first reflective network was TiO2 nanorods grown in-situ on the fiber surface, and the second reflective network was TiO2 particles embedded in the fiber. The bionic fiber was added to SiC aerogel as reinforcement to build composite aerogel. The results displayed that the "double network" reflecting ability of the bionic fiber can effectively shield the heat radiation conduction and thus reduce the effective thermal conductivity of the composite aerogel. The TiO2 nanorods of the fiber surface not only reflected the heat radiation but also enhanced the fiber/aerogel interface bonding. In addition, the composite aerogel exhibited low thermal conductivity, high ablation resistance and high compressive strength.