Electrical and magnetic properties of multiferroic BiFeO3-based flexible composites

Abstract

Flexible composite samples were prepared by hot pressing of BiFeO3 powders prepared by chemical methods with polyvinylidene fluoride (PVDF). Role of PVDF is not only to make the samples flexible, but also to improve the properties of BiFeO3, primarily to prevent the problems with high density of leakage currents. Microstructure of composites showed good homogeneity and uniform thickness of around 50 μm. Dielectric, impedance, ferroelectric and ferromagnetic properties of composite samples were studied and compared with those of BiFeO3 powders or ceramic samples. Flexible samples exhibited improved electrical resistivity, which enables them to withstand significantly higher electric fields and to be weakly polarized. By eliminating the sintering step, it is possible to retain weak ferromagnetism originating from Fe3O4 nanoparticles formed during the synthesis in compact samples. Acknowledgement: The authors would like to acknowledge the financial support of the Ministry of Education, Science and Technological development of the republic of Serbia, Project no. III 45021 and the Brazilian research agencies CAPES, CNPq, and FAPESP-CEPID/CDMF 2013/07296-2.