1. Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230088, China; 2. University of Science and Technology of China, Hefei 230026, China; 3. Key Laboratory of Photovoltaic and Energy Conservation Materials, Chinese Academy of Sciences, Hefei 230088, China
Abstract: SiO2 nanofibers-SiO2 composite aerogel is prepared through sol-gel method,trimethyl chlorosilane-leading surface modification method and atmospheric pressure drying method,with tetraethyl orthosilicate (TEOS) as silicon source and in-situ synthesized SiO2 nanofibers as reinforcing phase.The structure and properties of the composite aerogel are characterized by scanning electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,BET surface analysis and thermogravimetric analysis.The effects of SiO2 nanofibers on the aerogels are also investigated.The results show that the addition of SiO2 nanofibers can form an effective framework structure to improve the micro morphology and space structure of the aerogel with good compatibility,dispersion and thermal stability,maintaining high porosity.The obtained composite aerogel has a pore size in the range of 10-20 nm and a porosity of 97%.
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