TITANIA AEROGELS: PREPARATION AND CHARACTERIZATION

摘要

Titania aerogels were prepared by hydrolysis of titanium tetrachloride at room temperature followed by the supercritical drying procedure. These aerogels exhibit interesting high surface area and large pore volume mainly in the range of mesopore to macropore. The influence of the preparation parameters and heat treatment on the textural and structural properties of titania aerogels had been systematically studied. The pH value of the original hydrogel is one of the most important influential factors. The specific surface area and pore volume of the aerogels ranged from 53.3 to 195.1m~2/g and 0.15 to 0.81cm~3/g, respectively, depending on preparation conditions. The mean crystal-size was in the range of 7.6 to 32.8nm. All the aerogels were crystallized in the form of anatase regardless of the preparation conditions. The specific surface area and pore volume were found to decrease with increasing heat-treatment temperature.