Polyol based auto-combustion synthesis of nanostructured PZT and its characterization

Free standing, monophase perovskite of the formula PbZr0.52Ti0.48O3 (PZT) is obtained at a low calcination temperature of 500 °C using self-sustaining polyol auto-combustion method. A redox type exothermic reaction takes place during the synthesis process, in which the nitrate ions of the precursor act as oxidizing agent and the ethylene glycol as a fuel for the reaction which is being reduced. FTIR and TG-DTA studies, confirmed the PZT formation and reaction process involved in the synthesis. The effect of sintering temperature on phase formation, studied by XRD indicates high temperature stability for the tetragonal phase in the synthesized PZT. XRD further revealed a crystallite size of ∼6 nm and it increases to 20 nm as the sintering temperature increases from 500 to 1000 °C. SEM, TEM and AFM images clearly show presence of non agglomerated nanoparticles with spherical shape. Dielectric measurements carried out in the temperature range 30–500 °C at various frequencies, revealed a high dielectric constant of 332 and dielectric loss of 0.035 at room temperature. Further, there is increase in dielectric constant of the material with the sintering temperature. Finally, the change in structural property with sintering temperature is correlated with the dielectric studies.