Stable nanocrystalline zirconia sols prepared by a novel method: Alcohol thermal synthesis

Nanocrystalline zirconia sols with a metastable cubic phase were synthesized from diglycol-modified zirconium n-propoxide via a novel method, alcohol thermal synthesis. The chemical bonding of diglycol with zirconium was found to be important in obtaining stable nanocrystalline zirconia sols. Sols produced in this way were translucent with the primary particles of 4-nm crystallites, and the corresponding gel was shown to be mesoporous with a pore size from 2.5 to 3.8 nm and Brunauer—Emmett—Teller surface areas between 130 and 266 m² g⁻¹. This indicates that alcohol thermal synthesis shares the advantages of both the sol-gel process and hydrothermal synthesis.