Ceramic Meta-Aerogel with Thermal Superinsulation up to 1700°C Constructed by Self-Crosslinked Nanofibrous Network via Reaction Electrospinning.

Abstract

Thermal insulation under extreme conditions requires the materials to be capable of withstanding complex thermo-mechanical stress, significant gradient temperature transition, and high-frequency thermal shock. The excellent structural and functional properties of ceramic aerogels make them attractive for thermal insulation. However, in extremely high-temperature environments (above 1500°C), they typically exhibit limited insulation capacity and thermo-mechanical stability, which may lead to catastrophic accidents, and this problem has never been effectively addressed. Here, we design a novel ceramic meta-aerogel constructed from a crosslinked nanofiber network using a reaction electrospinning strategy, which ensures excellent thermo-mechanical stability and superinsulation under extreme conditions. The ceramic meta-aerogel has an ultralow thermal conductivity of 0.027W m-1 k-1, and the cold surface temperature is only 303°C in a 1700°C high-temperature environment. After undergoing a significant gradient temperature transition from liquid nitrogen to 1700°C flame burning, the ceramic meta-aerogel can still withstand thousands of shears, flexures, compressions, and other complex forms of mechanical action without structural collapse. This work provides new insight into developing ceramic aerogels that can be used for a long period in extremely high-temperature environments. This article is protected by copyright. All rights reserved.