Double-negative-index ceramic aerogels for thermal superinsulation

Document Type

Article

Publication Date

2-15-2019

Abstract

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.

Identifier

85061586988 (Scopus)

Publication Title

Science

External Full Text Location

https://doi.org/10.1126/science.aav7304

e-ISSN

10959203

ISSN

00368075

PubMed ID

30765563

First Page

723

Last Page

727

Issue

6428

Volume

363

Grant

51602078

Fund Ref

National Natural Science Foundation of China

This document is currently not available here.

Share

COinS