改进两步法制备高透光率SiO_2气凝胶的研究  

Transparent Silica Aerogel Prepared by Improving the Two Steps

作　　者：刘文洋[1,2,3] 罗炫[2] 曹林洪[1,3] 方瑜[2] 杨睿戆[2] 张庆军[2] 蒋晓东[2] 

机构地区：[1]西南科技大学材料科学与工程学院,绵阳621010 [2]中国工程物理研究院激光聚变研究中心,绵阳621900 [3]西南科技大学中国工程物理研究院激光聚变研究中心极端条件物质特性联合实验室,绵阳621010

出　　处：《硅酸盐通报》2016年第2期550-554,共5页Bulletin of the Chinese Ceramic Society

基　　金：中国工程物理研究院科学技术发展项目基金(2015B0302071);中国工程物理研究院发展基金项目(2013A0302016);西南科技大学重点科研平台专职科研创新团队建设基金项目(14tdjk04);2013年四川省学术与技术带头人培养资金资助

摘　　要：以正硅酸甲酯为硅源,采用溶剂甲醇和N,N-二甲基甲酰胺,通过酸碱两步催化溶胶-凝胶法,结合CO2超临界干燥技术制备出高透光率SiO_2气凝胶。利用扫描电镜、比表面积和空隙分析仪、紫外-可见分光光度计对该气凝胶的结构和光学性能进行了研究。结果表明,用N,N-二甲基甲酰胺为溶剂获得的气凝胶具有好的三维纳米多孔结构,平均孔径15.16 nm,比表面积922.1 m2/g;0.4 cm厚的样品在波长800 nm处的透光率高达92.4%。由于该气凝胶具有较高的透过率,因此在太阳能集热器方面具有极高的应用价值。The highly transparent silica aerogels were successfully prepared by sol-gel process and subsequently supercritical drying with carbon dioxide. Tetramethyl orthosilicate was used as Si source, methyl and N, N-Dimethylformamide was used as solvent. The structures and optical properties of the silica aerogel were characterized by SEM, BET and UV. The results indicated that the sample possessed three-dimensional nano porous structure, with average pore size of 15.16 nm and specific surface area of 922.1 m2/g. The transmittance of the sample which had a thickness of 0.4 cm was up to 92.4% at the wavelength of 800 nm. With its high transmittance, this kind of silica aerogels has a potential application in the field of solar collector.

关 键 词：SiO_2气凝胶 DMF 两步法 溶胶-凝胶 透光率 

分 类 号：O648[理学—物理化学]