Gao Shuai, Cao Zeqi, Liu Kai, Liu Shuning, Pang Wanjun, Jiang Hongyi
School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China.
Polymers (Basel). 2024 Aug 14;16(16):2296. doi: 10.3390/polym16162296.
To reduce production costs and enhance the high-temperature resistance of SiO aerogels, an aluminum-doped silica aerogel (ASA) was successfully prepared using the sol-gel method and atmospheric drying method. The composite silica sources included TEOS and inexpensive acidic silica sol, while the aluminum source was aluminum sol. The study investigated the influence of the molar ratio of acidic silica sol to TEOS, Al/Si, and calcination temperature on the composition, structure, and high-temperature resistance of the ASA. The results indicate that a sample with an acidic silica sol to TEOS molar ratio of 0.8 achieved a specific surface area of 683.204 m·g. The Al/Si molar ratio significantly impacted the high-temperature resistance of the ASA, with the sample having a molar ratio of 0.02 Al/Si displaying the highest specific surface area of 705.956 m·g at 600 °C. Moreover, this surface area remained at 273.099 m·g after calcination at 1000 °C, notably higher than the sample without aluminum sol (16.082 m·g). Mechanism analysis indicated that the addition of aluminum sol to the SiO aerogel inhibited phase transitions, and both acidic silica sol and aluminum sol particles enhanced the aerogel structure, contributing to a marked improvement in high-temperature resistance.
为降低生产成本并提高SiO气凝胶的耐高温性能，采用溶胶-凝胶法和常压干燥法成功制备了铝掺杂二氧化硅气凝胶（ASA）。复合二氧化硅源包括正硅酸乙酯（TEOS）和廉价的酸性硅溶胶，而铝源为铝溶胶。该研究考察了酸性硅溶胶与TEOS的摩尔比、Al/Si以及煅烧温度对ASA的组成、结构和耐高温性能的影响。结果表明，酸性硅溶胶与TEOS摩尔比为0.8的样品比表面积达到683.204 m²/g。Al/Si摩尔比对ASA的耐高温性能有显著影响，Al/Si摩尔比为0.02的样品在600℃时比表面积最高，为705.956 m²/g。此外，该样品在1000℃煅烧后比表面积仍为273.099 m²/g，明显高于未添加铝溶胶的样品（16.082 m²/g）。机理分析表明，向SiO气凝胶中添加铝溶胶可抑制相变，酸性硅溶胶和铝溶胶颗粒均增强了气凝胶结构，从而显著提高了耐高温性能。
