Bio-inspired gradient multilayer ceramic fiber aerogel loaded with TaSi2 and WSi2: Fabrication, anti-oxidation and thermal insulation

Aerogel is widely used in the field of thermal insulation. However, aerogel exhibits brittleness and infrared radiation transparency at high temperatures. Fiber composite aerogel achieved great progress, but the homogeneous structure hardly allowed heat convection, heat conduction, and heat radiation to be controlled simultaneously. In this paper, inspired by bamboo's multilayer and gradient structure, SiC fiber loaded with TaSi2 and WSi2 antioxidant particles was prepared by electrostatic spinning. The fiber was incorporated into the silicoboron carbonitride (SiBCN) aerogel to prepare gradient multilayer SiC/SiBCN ceramic fiber aerogel. The fiber network enhanced the mechanical properties. Antioxidant particles improved antioxidant performance. Heat radiation was reduced through the fiber, while heat conduction and heat convection were decreased by the aerogel. The results showed that the ceramic fiber aerogel exhibited ultra-low thermal conductivity, excellent infrared radiation shielding, and antioxidation performance. This study is expected to provide new ideas for constructing high-temperature thermal insulation ceramic fiber aerogel.