Properties of Alumina-Zirconia Powder Prepared from Aluminium Chelate Compound and Zirconium Alkoxide

Abstract

Alumina-zirconia powder (AZ) was prepared by thermal decomposition of organic precursors synthesized from ethyl acetoacetate aluminium diisopropoxide and zirconium tetra-n-butoxide. The specific surface area of AZ was higher than that of alumina-zirconia powder (ALK) prepared from aluminium tri-sec-butoxide and zirconium tetra-n-butoxide in the range of 0-40mol% ZrO₂. The pore radius for AZ containing 0-40mol% ZrO₂ distributed from 1 to 3nm. The true density of AZ was lower than that of ALK in the range of 0-40mol% ZrO₂. Four- and 6-coordinated Al atoms existed in ZrO₂-free AZ, while 5-coordinated Al atoms in addition to 4- and 6-coordinated Al atoms existed in AZ containing 20-80mol% ZrO₂. These results indicate that alumina component and zirconia component in AZ were mixed homogeneously at the atomic level.