A comparative study of dielectric, ferroelectric and magnetic properties of BiFeO3 multiferroic ceramics synthesized by conventional and spark plasma sintering techniques

BiFeO3 ferrite ceramics were synthesized by spark plasma sintering (SPS) and conventional solid-state synthesis in conjunction with high-energy ball milling. They were evaluated by different characterization techniques such as X-ray diffraction, scanning electron microscopy, and dielectric, ferroelectric and magnetic measurements. The 750 degrees C-SPS prepared ceramic samples possessed a single perovskite structure and they were compared with the conventionally synthesized ones. The relative density and average grain size were approximately 95% and <200 nm for the SPS-prepared samples, while they were about 89% and >300 nm for the conventionally prepared ones. In comparison with the conventionally synthesized ceramics, the SPS-prepared ones exhibited improved dielectric, ferroelectric and magnetic properties. These should be associated with high-density, fine-grained and uniform microstructure created by SPS in conjunction with high-energy ball milling, which could be a promising technique for fabricating high-quality BiFeO3 multiferroic ceramics. (C) 2014 Elsevier Ltd. All rights reserved.