Synthesis of PLSnZT ceramics with large displacement constants via a sol-gel colloidal process

The PLSnZT powders were obtained from soluble peroxide precursors of Ti(IV) and Zr(IV) by precipitation with lead nitrate, lanthanum nitrate and tin chloride solutions. The precipitation of Pb(II), Ti(IV) and Zr(IV) from solution in pseudobinar systems was studied as a function of pH and temperature. The structural evolution of powders was studied using XRD. The powders were pressed, sintered, coated with silver paste and poled in silicon oil at high voltage. The density, contraction, electrical permitivity ε 33 and displacement constants d31 were determined as a function of composition and thermal treatment temperature. The same values were measured for the material with the same composition obtained in the classical ceramic route by solid-state reaction. The density (8.l g/cm-3), relative electrical permitivity (500) and d31 (16.10-12 m.V-1) obtained by the sol-gel colloidal route at a sintering temperature of 1100°C were 30-40% higher comparing with the same constants in the classical route at a sintering temperature of 1250-1300°C.