# All‐In‐One Thermal Protection: Multifunctional Synergy in Hierarchically Structured Dual‐Oxide Nanofiber Aerogel

## TL;DR

A new ceramic nanofiber aerogel is developed that is lightweight, heat-resistant, and thermally insulating, with potential for various applications.

## Contribution

The paper introduces a hierarchical fibrous aerogel with a dense-sheath/porous-core structure that overcomes brittleness and provides thermal protection.

## Key findings

- The aerogel has ultra-low thermal conductivity of 7 mW·m−1·K−1 and a minimum density of 8 mg·cm−3.
- It maintains mechanical stability from −196 to 1300 °C with 80% compression.
- The aerogel shows resistance to thermal vibration and potential for noise absorption and catalytic conversion.

## Abstract

Ceramic nanofiber aerogels are emerging as promising thermal protection materials, yet their brittleness remains a critical challenge. This work designs a hierarchical fibrous aerogel consisting of streamlined dual‐oxide nanofibers featuring a dense‐sheath/porous‐core architecture, simultaneously overcoming the intrinsic fragility while enabling thermal‐protection. The obtained aerogel demonstrates ultra‐low thermal conductivity and exceptional thermomechanical stability a high working temperatures. The aerogel structure, constructed from arbitrarily bendable nanofibers, reduces the overall density and effectively lowers thermal conductivity. The minimum density can reach as low as 8 mg·cm−3. This unique structure enhances the mechanical stability of the entire aerogel in a wide working temperature (−196 to 1300 °C) upon 80% compression. The thermal conductivity achieves an extremely low value of 7 mW·m−1·K−1. These attributes originate from the following mechanisms: depressing heat transfer by prolonging heat conduction pathways and offering interfacial insulation, while impeding phonon transport within nanopores. Upon simulated space‐ground integrated experiments at ≈1200 °C, the ceramic nanofiber aerogel exhibits remarkable resistance to thermal vibration. The nanofiber aerogel can serve as an all‐in‐one platform to synergistically integrate noise absorption and catalytic conversion, thereby paving the way for future practical applications.

Through a cross‐scale structural design, a lightweight, heat‐resistant, and thermal‐insulating streamlined dual‐oxide nanofiber aerogel is prepared to achieve exceptional thermomechanical stability. Structural design of ceramic fibrous aerogel toward thermal protection, illustrating thermal insulation and stress dissipation. The streamlined dual‐oxide fibrous aerogel shows promising potential for a wide range of applications, from air to ground.