氧化铝气凝胶的合成与性能

氧化铝气凝胶具有大比表面积、高孔隙率以及比氧化硅气凝胶更优异的热稳定性, 在高温隔热和催化领域有广阔的应用前景, 但其复杂的合成工艺和较低的强度限制了其应用。本文首先介绍氧化铝气凝胶合成工艺, 指出溶胶-凝胶过程中存在的问题, 不同干燥方式的特点以及最新发展的干燥工艺; 然后介绍了近年来氧化铝气凝胶在比表面积、热稳定性、强度、导热系数等性能改善方面所取得的代表性研究成果; 最后介绍了氧化铝气凝胶在高温催化、隔热领域的应用, 并展望了未来氧化铝气凝胶的发展方向以及应关注的问题。

Synthesis and Property of Alumina Aerogel

Alumina aerogel has wide application prospect in high temperature thermal insulation and catalytic fields due to its high specific surface area, high porosity, and better thermal stability than silica aerogel. However, the complicated synthetic process and the low strength of alumina aerogel restrict their application. In this review, the synthetic process of alumina aerogel is firstly introduced. Some problems existed in the Sol-Gel process, the characteristics of various drying methods, and the latest drying methods developed by researchers are pointed out. Then, some representation achievements in the performance improvements on specific surface area, thermal stability, thermal conductivity and compressive strength of alumina aerogel in recent years are summarized. Finally, the development and application of alumina aerogel in high temperature catalytic and thermal insulation fields are introduced, their development tendency is prospected, and some issues on the study of alumina aerogel are highlighted.