Synthesis of high surface area zirconia aerogels using high temperature supercritical drying

Zirconia aerogels were prepared by a sol-gel method followed by high temperature supercritical drying. Aerogels prepared in this way had surface areas up to 565 m(2)/g after drying and above 100 m(2)/g after calcination at 500 degrees C for 2 hours. The calcined samples had symmetrical pore size distributions with average pore radii 70-170 Angstrom and pore volumes 0.5-0.8 m(3)/g. Influence of preparation parameters such as precursor and solvent type,precursor and acid concentration, hydrolysis ratio, aging time, supercritical drying and subsequent calcination temperatures on the properties of the aerogels was studied systematically. Sol-gel preparation stabilized the tetragonal crystalline phase.