Preparation of Al 2 O 3 -SiO 2 Aerogel by Supercritical Drying

作者：Xiaofeng Sui, Jing-Bing Xu, L. Zhang, Ruilin Liu, Chang Ling Zhou, K.Y. Wang · 发表于：IOP Conference Series Materials Science and Engineering · 年份：2019 · DOI：10.1088/1757-899x/678/1/012008 · 被引用次数：2 · 研究领域：Aerogels and thermal insulation、Mesoporous Materials and Catalysis、Pigment Synthesis and Properties

Abstract Al 2 O 3 -SiO 2 aerogel was prepared through sol-gel process and ethanol supercritical drying technology using aluminum chloride hexahydrate (AlCl 3 •6H 2 O) and tetraethoxysilane (TEOS) as precursors. Structures and properties of Al 2 O 3 -SiO 2 aerogel were investigated by means of BET, XRD, SEM, FTIR, TG-DTA. At room temperature, the specific surface area of Al 2 O 3 -SiO 2 aerogel was 574m 2 •g −1 , and the average pore size was 26.34nm. The three-dimensional network skeleton was composed of leaf shape particles. Al 2 O 3 -SiO 2 aerogel went through the transformation process of γ-AlOOH + amorphous SiO 2 → γ-Al 2 O 3 + amorphous SiO 2 → Mullite (3Al 2 O 3 •2SiO 2 ) when heat treatment temperature increased from room temperature to 1200°C. At 1200°C, the specific surface area was 162m 2 •g −1 , the average pore size was 59.91nm.It was indicated that Al 2 O 3 -SiO 2 aerogel possessed excellent high temperature stability and heat insulation performance.