Al2O3–C–SiO2 Nanofibrous Aerogel-like Composites for Thermal Insulation

Ceramic aerogels exhibit significant advantages for thermal insulation applications. However, their practical utilization is hindered by high manufacturing costs, inherent brittleness, and inadequate thermal resistance. In this study, inspired by the dual-network architecture of the human skin dermis, we developed a biomimetic aerogel-like ceramic thermal insulator (ACSM) via a scalable electrospinning and sol–gel strategy. The structural design integrates rigid alumina nanofibers with flexible carbon fibers, which are consolidated into a stable three-dimensional porous framework via nanoscale silica welding. This distinctive fibrous network imparts the material with a low bulk density (0.1107–0.1217 g/cm3), commendable compressive strength (0.31–1.76 MPa), and ultralow thermal conductivity (0.0512–0.0624 W/(m·K)). Furthermore, the three-dimensional mesh structure of the ACSM remains intact after heat treatment at 800 °C in a nitrogen atmosphere, confirming its exceptional thermal stability. Importantly, the material’s comprehensive performance can be precisely tuned by modulating the relative content of the two fiber components. This study establishes a robust foundation for the future development of advanced nanostructured biomimetic thermal insulation materials, with potential applications in aerospace, energy-efficient buildings, and thermal management.