Preparation Of Titanium Aerogels With Sol-Gel Method By Supercritical Drying Technique

Titanium aerogels are advanced nanometer materials that have high porosity and specific surface area, varied chemical structures, fascinating and useful properties. Supercritical fluid drying technique is one of important methods for aerogels' preparation.In this thesis, titanium aerogels were prepared with sol-gel method by supercritical drying technique. The titanium dioxide alcogels were made from titanium tetrabutoxide, water and ethanol at certain molar ratio. Monolithic aerogels were prepared by supercritical carbon dioxide drying technique, and nanometer powder was prepared by supercritical ethanol drying technique.The sol-gel process has been studied under different conditions, and the optimum condition for preparing titanium hydrogels at room temperature was given. Besides, the influence factors and mechanism of sol-gel process has been discussed. In the process of supercritical drying, some of the main influence factors were analyzed.The structural and other physical properties of the products have been characterized by means of XRD, BET, SEM, TEM and IR analysis. The results show that the monolithic aerogels were coherent, non-crystalline, low density, high specific surface areas, nanosized porous solid materials. The titanium dioxide powder was anatase and consists of nanometer particles with great specific surface areas.Cao Li (Applied Chemistry) Directed by professor Chen Kaixun...