Rare-earth modified PZT ceramics obtained by the OPM route and sintered using microwaves.

Abstract

This proposal will be executed in 24 months during the Master Course of Liliam Kaori Yamada in the Programa de Pós-graduação em Química (PPGQ/UFSCar), evaluated by CAPES with level 6. A new wet-chemical method of synthesis, which received the name "the oxidant peroxo method (OPM)", was recently developed to obtain ferroelectric oxides based in lead that will be used for the synthesis os new compositions of PZT modified with rare-earth elements. This technique is based in the oxy-reduction reaction between Pb(II) and some peroxo-complexes of titanium and rare-earth element in water, which will result in an amorphous precipitate of nanoparticles with controlled composition that will be crystallizes in the perovskite structure after a heat treatment at low temperature (below than 600 ºC). Two of the main advantages of the OPM route is the possibility to obtain uniform nanoparticles free of carbon or halides, and the use of water as solvent. It is of fundamental importance to understand the mechanism of crystallization and how this process determines the final properties of nanoparticles. For this reason, it is proposed the use of Raman spectroscopy, infrared absorption spectroscopy and the use of X-ray diffraction. We expect to find the best condition of heat treatment for the powder crystallization and the optimal condition of synthesis. Moreover, we expect to obtain highly dense ceramics of PZT modified by rare earth elements using microwaves that will result in better dielectric characteristic.