Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (2): 360-368.doi: 10.3866/PKU.WHXB201412243

• CATALYSIS AND SURFACE SCIENCE • Previous Articles     Next Articles

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).

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