PZT/PLZT ceramics prepared by hydrolysis and condensation of acetate precursors

Abstract

Titanyl zirconyl acetate was prepared by chelating titanium isopropoxide with acetic acid, and was used as a precursor in a sol-gel process to obtain PZT and PLZT powders. The combined results of the DTA/TGA, FTIR and SEM studies indicate that the PLZT-precursor contained a higher mol fraction of acetate groups and that polycondensation was slower, resulting in a small particle size for the PLZT powder. X-ray photoelectron spectroscopy (XPS) was used to detect Ti oxidation states on the surface of the PZT and PLZT bulk ceramics sintered at various temperatures. The Ti binding energy of the PLZT powders prepared at various temperatures were all lower than those of the corresponding PZT powders, indicating a relatively higher Ti 3+ concentration on the PLZT surface. This higher Ti 3+ surface concentration is responsible for the higher relative dielectric constant measured for the PLZT bulk ceramics.