Ultrastrong yet Superelastic Lamellar Ceramic Aerogels Achieved through Inter-Nanofiber Bonding for High-Temperature Thermal Insulation.

Ceramic aerogels are seen as ideal materials for thermal insulation applications under extreme conditions. But they often exhibit a considerable increase in thermal conductivity at high temperatures, which could lead to a serious catastrophe in actual applications. Meanwhile, simultaneously achieving high compressive strength and superelasticity for porous ceramic structures remains a challenge. Herein, we propose one kind of novel lamellar-structured ceramic nanofiber aerogel, where the deliberately tailored ZrP2O7 and AlPO4 are used as functional constituents and form inter-nanofiber bonding. By this strategy, the prepared aerogels achieve the synergistic integration of three core properties: a 90% fully recoverable strain that far outperforms the vast majority of reported ceramic aerogels, an ultrahigh compressive strength of 1097 kPa at 90% strain, and a thermal conductivity as low as 0.089 W·m- 1·K- 1 at 1000°C. The experimental and theoretical analysis results show that the unique layered structure with robust crosslinking design can effectively improve the structural stability and compressive strength, while phosphate compounds can reduce high-temperature radiative heat transfer. This work provides a new perspective for collaborative design of mechanical and thermal properties of advanced ceramic aerogels.