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Sintering of dense ceramics bodies of pure lead titanate obtained by seeding-assisted chemical sol-gel

Abstract:

Crack-free and dense lead titanate ceramics (∼97% of the theoretical density) has been prepared by a sol-gel method using titanium tetrabutoxide and lead acetate in stoichiometric proportion and without the additions of dopants. Crystalline nanometer-sized PbTiO3 seeds have been added to the precursor solution in a proportion of 10 wt%, allowing the preparation of pure PbTiO3 perovskite phase at temperatures as low as 400°C. The remanent polarization of sintered samples was 1.73 μC/cm2 and the coercive field 33 kV/cm. These values were in agreement with those reported for dense PbTiO3. The Curie temperature was around 440°C, slightly lower than the theoretical value (490°C). It was observed that an increase in the sintering temperature and grain size resulted in an increase in the tetragonal distortion of the perovskite phase. © 2001 Elsevier Science Ltd. All rights reserved.