Multiferroic Properties of Nanocrystalline PbTiO_3 Ceramics

摘要

Nanocrystalline PbTiO_3 (PTO) powders in a perovskite structure have been synthesized by the sol-gel process using lead acetate, glycerin, and titanium (IV) isopropoxide as precursors. PTO ceramics were obtained by sintering the powders at temperatures ranging from 600° to 1000℃. The structure and morphology of the ceramics have been determined by X-ray diffraction, transmission electron microscopy, and field emission scanning electron microscopy. The PTO powder calcined at 450 ℃ shows weak ferromagnetism at room temperature. The PTO ceramics sintered at various temperatures exhibit coexistence of ferroelectricity and weak ferromagnetism at room temperature. Enhancement in the magnetic moment and ferroelectricity with a reduction in the grain size of PTO ceramics was observed. This result facilitates the possibilities of new perovskite electromagnetic devices at the nanoscale level.