文献类型：期刊文献

英文题名：SiZrOC Aerogels with Low Thermal Conductivity and Enhanced Thermal Stability for Applications in High-Temperature Nanoscale Thermal Insulators

作者：Han, Yuqing[1];Wu, Youqing[1];Huang, Sheng[1,2];Zhang, Hong[3];Liang, Zijun[1];Guan, Xuebo[3];Wu, Shiyong[1,2]

机构：[1]East China Univ Sci & Technol, Dept Chem Engn Energy Resources, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Engn Res Ctr Resource Utilizat Carbon Containing W, Minist Educ, Shanghai 200237, Peoples R China;[3]Naicher New Mat Yingkou Co Ltd, Yingkou 115004, Peoples R China

年份：2023

卷号：6

期号：22

起止页码：21169

外文期刊名：ACS APPLIED NANO MATERIALS

收录：;EI(收录号：20234915144601);WOS:【SCI-EXPANDED(收录号:WOS:001109819900001)】；

基金：This work was supported by the key technologies program of the Yingkou Science and Technology Bureau [Item No. 2022JH3/0200003].

语种：英文

外文关键词：SiZrOC aerogel; pore structure; thermal stability; phase separation; nanomaterial; thermal insulationmaterial

摘要：The continuous, random three-dimensional nanostructure of aerogels is the key determinant of their exceptional thermal insulating performance. However, at elevated temperatures, sintering can lead to disruption of this nanostructure. SiOC and SiZrOC aerogels were prepared by pyrolyzing organic-inorganic precursor aerogels at 1000 degrees C under an Ar atmosphere. The pyrolysis treatment resulted in the formation of a Si-O-C structure with excellent thermal stability. Following calcination at 1000 degrees C for 0.5 h, SiZrOC demonstrated a specific surface area retention rate of 76.8% and a pore volume retention rate of 75.8%, surpassing the most advanced ZrO2-SiO2 aerogel. Additionally, SiZrOC consistently exhibited outstanding thermal insulation performance, with thermal conductivities of 0.0273 and 0.0332 W m(-1) K-1 before and after calcination at 1000 degrees C, respectively. Notably, it was observed for the first time that the rearrangement of Si-C and Si-O bonds caused by pyrolysis induced a loosening effect on the SiO4 structure within the aerogel. Consequently, during subsequent aerobic calcination, SiOC and SiZrOC underwent another phase separation stage, resulting in a further increase in the number of Si-O-C structures, which offers an approach to improve thermal insulation properties in extreme environments. The superior thermal stability and thermal insulation performance make SiZrOC a promising candidate for applications in high-temperature nanoscale thermal insulation materials.