Journal Article

Double-negative-index ceramic aerogels for thermal superinsulation

Chen, Wenli, Duan, Xiangfeng, Zhao, Zipeng, Peng, Lele, Wang, Tao, Ren, Xuexin, Fei, Huilong, Zhang, Xiang, Zhang, Qiangqiang, Hu, Yuan, Zhu, Jian, Sun, Hongtao, Xu, Xiang, Shakir, Imran, Lin, Zhaoyang, Cheng, Gary J., Huang, Yu, Li, Hui, Wan, Chengzhang, Hao, Menglong, Fisher, Timothy S., Du, Tao, Dames, Chris, Wang, Lei, Wang, Chen, Deng, Biwei

2019

Overview

Ceramic aerogels are attractive for thermal insulation but plagued by poor mechanical stability and degradation under thermal shock. In this study, we designed and synthesized hyperbolic architectured ceramic aerogels with nanolayered double-pane walls with a negative Poisson’s ratio (−0.25) and a negative linear thermal expansion coefficient (−1.8 × 10−6 per °C). Our aerogels display robust mechanical and thermal stability and feature ultralow densities down to ∼0.1 milligram per cubic centimeter, superelasticity up to 95%, and near-zero strength loss after sharp thermal shocks (275°C per second) or intense thermal stress at 1400°C, as well as ultralow thermal conductivity in vacuum [∼2.4 milliwatts per meter-kelvin (mW/m·K)] and in air (∼20 mW/m·K). This robust material system is ideal for thermal superinsulation under extreme conditions, such as those encountered by spacecraft.

• Publisher: American Association for the Advancement of Science,The American Association for the Advancement of Science
• Subject: Aerogels / Ceramics / Commercial spacecraft / Commercialization / Dimensional stability / Graphene / Mechanical properties / Metamaterials / Poisson's ratio / Spacecraft / Superelasticity / Thermal conductivity / Thermal expansion / Thermal insulation / Thermal shock / Thermal stability / Thermal stress / Vacuum