Preparation of nano silicon dioxide with sol-gel method

The influences of temperature, compounds dosages and water on the size of nano silica prepared by tetraethyl orthosilicate were discussed, and the transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FTIR) were employed to investigate the characteristics of the nano silica synthesized by the sol-gel method. Moreover, the silane coupling agent was also used to modify the surface characteristic of the nano silica. Results showed that the influences of temperature, compounds dosages and water on the size of nano silica had a significant impact. In fact, the optimal synthesis temperature was 45 degrees centigrade, and the stirring time was 2 hours. In this case, the nano silica can be prepared with the grain size of 100 nm and the narrow particle size distribution. By FTIR analyzing, it can be seen that the combination of the nano silica and the silane coupling agent was chemical reaction. In addition, the tests showed that the adsorption process finished in 40 minutes.