Chemically bonded multi-nanolayer inorganic aerogel with a record-low thermal conductivity in a vacuum  

作　　者：Hongxuan Yu Menglin Li Yuanpeng Deng Shubin Fu Jingran Guo Han Zhao Jianing Zhang Shixuan Dang Pengyu Zhang Jian Zhou Dizhou Liu Duola Wang Chuanwei Zhang Menglong Hao Xiang Xu 

机构地区：[1]Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology,and Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education,Harbin Institute of Technology,Harbin 150090,China [2]Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education,School of Energy and Environment,Southeast University,Nanjing 210096,China [3]Key Lab of Aerospace Bearing Technology and Equipment of the Ministry of Industry and Information Technology,Harbin Institute of Technology,Harbin 150001,China

出　　处：《National Science Review》2023年第10期91-100,共10页国家科学评论（英文版）

基　　金：funding support from the National Key Research and Development Program of China(2022YFC3005800);funding support from the National Key Research and Development Program of China(2018YFB2000301);the Heilongjiang Touyan Innovation Team Program of China;funding support from the National Natural Science Foundation of China(52076041);the Natural Science Foundation of Jiangsu Province(BK20200371)。

摘　　要：Inorganic aerogels have exhibited many superior characteristics with extensive applications,but are still plagued by a nearly century-old tradeoff between their mechanical and thermal properties.When reducing thermal conductivity by ultralow density,inorganic aerogels generally suffer from large fragility due to their brittle nature or weak joint crosslinking,while enhancing the mechanical robustness by material design and structural engineering,they easily sacrifice thermal insulation and stability.Here,we report a chemically bonded multi-nanolayer design and synthesis of a graphene/amorphous boron nitride aerogel to address this typical tradeoff to further enhance mechanical and thermal properties.Attributed to the chemically bonded interface and coupled toughening effect,our aerogels display a low density of 0.8 mg cm-3 with ultrahigh flexibility(elastic compressive strain up to 99%and bending strain up to 90%),and exceptional thermostability(strength degradation<3%after sharp thermal shocks),as well as the lowest thermal conductivities in a vacuum(only 1.57 mW m-1 K-1 at room temperature and 10.39 mW m-1 K-1 at500℃)among solid materials to date.This unique combination of mechanical and thermal properties offers an attractive material system for thermal superinsulation at extreme conditions.

关 键 词：inorganic aerogels multi-nanolayer mechanical-thermal tradeoff flexibility thermal superinsulation 

分 类 号：O648.17[理学—物理化学]