物理化学学报 >> 2015, Vol. 31 >> Issue (2): 360-368.doi: 10.3866/PKU.WHXB201412243

催化和表面科学 上一篇    下一篇

耐高温核/壳结构TiO2/SiO2复合气凝胶的制备及其光催化性能

祖国庆, 沈军, 王文琴, 邹丽萍, 许维维, 张志华   

  1. 同济大学波耳固体物理研究所, 上海市人工微结构材料与技术重点实验室, 上海 200092
  • 收稿日期:2014-11-13 修回日期:2014-12-23 发布日期:2015-01-26
  • 通讯作者: 祖国庆, 沈军 E-mail:zuguoqing863@gmail.com;shenjun67@tongji.edu.cn
  • 基金资助:

    国家自然科学基金(51172163, U1230113), 国家科技支撑计划(2013BAJ01B01), 国家高技术研究发展计划项目(863) (2013AA031801), 上海市纳米科委专项基金(11nm0501600, 12nm0503001)资助

Preparation of Heat-Resistant, Core/Shell Nanostructured TiO2/SiO2 Composite Aerogels and Their Photocatalytic Properties

ZU Guo-Qing, SHEN Jun, WANG Wen-Qin, ZOU Li-Ping, XU Wei-Wei, ZHANG Zhi-Hua   

  1. Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092, P. R. China
  • Received:2014-11-13 Revised:2014-12-23 Published:2015-01-26
  • Contact: ZU Guo-Qing, SHEN Jun E-mail:zuguoqing863@gmail.com;shenjun67@tongji.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (51172163, U1230113), National Key Technology R&D Program of China (2013BAJ01B01), National High Technology Research and Development Program of China (863) (2013AA031801), and Shanghai Committee of Science and Technology (11nm0501600, 12nm0503001).

摘要:

以钛酸四丁酯为源, 采用苯胺-丙酮原位生成水溶胶-凝胶法, 在乙醇超临界干燥过程中用部分水解的钛醇盐和硅醇盐对TiO2凝胶进行超临界修饰制备了具有核/壳纳米结构的块体TiO2/SiO2复合气凝胶. 制备的复合气凝胶具有优异的机械性能, 其杨氏模量可达4.5 MPa. 复合气凝胶同时具有极好的高温热稳定性. 经过1000 ℃热处理后, 线性收缩由纯TiO2气凝胶的31%降至复合气凝胶的10%, 且比表面积由纯TiO2气凝胶的31 m2·g-1提升至复合气凝胶的143 m2·g-1. 此外, 该复合气凝胶经1000 ℃热处理后具有优异的光催化降解亚甲基蓝的性能. 其优异的光催化性能得益于TiO2/SiO2复合气凝胶1000 ℃处理后高的比表面积和小的颗粒尺寸. 优良的耐热性能、力学性能和光催化性能使获得的具有核/壳纳米结构的TiO2/SiO2复合气凝胶在光催化领域具有良好的应用前景.

关键词: TiO2/SiO2复合气凝胶, 核/壳纳米结构, 原位生成水, 超临界修饰, 耐高温, 光催化

Abstract:

Core/shell nanostructured monolithic TiO2/SiO2 composite aerogels were prepared by the anilineacetone in situ water formation sol-gel method. Titanium(IV) n-butoxide was used as a precursor followed by supercritical modification with partially hydrolyzed titanium alkoxide and tetraethoxysilane during ethanol supercritical fluid drying. The obtained composite aerogel showed excellent mechanical strength with a Young's modulus of 4.5 MPa. The composite aerogel exhibited excellent heat resistance. After heat treatment at 1000 ℃ its linear shrinkage decreased from 31% for the TiO2 aerogel to 10% for the composite aerogel. The specific surface area increased from 31 m2 ·g-1 for the TiO2 aerogel to 143 m2 ·g-1 for the composite aerogel. The composite aerogel exhibited excellent photocatalytic performance during the degradation of methylene blue after heat treatment at 1000 ℃. Its excellent photocatalytic property is attributed to its high specific surface area and the small particle size of the composite aerogel after heat treatment at 1000 ℃. The enhanced heat resistance, mechanical strength, and photocatalytic performance makes the obtained core/shell nanostructured TiO2/SiO2 composite aerogel a promising candidate for photocatalytic applications.

Key words: TiO2/SiO2 composite aerogel, Core/shell nanostructure, In situ water formation, Supercritical modification, Heat resistance, Photocatalysis

MSC2000: 

  • O648