Dielectric Properties of BaTiO3-Modified BiFeO3 Ceramics

Abstract

Multiferroic BiFeO3 has attracted extensive interest due to its potential in several applications. However, pure-phase BiFeO3 is very difficult to obtain. Hence, mixing BiFeO3 with other ferroelectrics, such as BaTiO3, is another approach to obtain materials with possible multiferroic properties. In this study, the BiFeO3 was modified with addition of BaTiO3 via a simple solid state reaction method. Dielectric properties of the BaTiO3-modified BiFeO3 ceramics were investigated over wide range of temperature and frequency. The results show that the (1-x)BiFeO3-xBaTiO3 ceramics with x = 0.1 and 0.2 exhibited large dielectric properties with giant-dielectric-like behavior. The dielectric properties were seen to improve with increasing BaTiO3 content, with the highest dielectric constant (ϵr = 19000) observed in 0.8BiFeO3-0.2BaTiO3 ceramic. The results were explained in terms of the pre-dominantly intrinsic BiFeO3 giant-dielectric behavior as a result of Fe multivalent states, as well as a better grain packing density with increasing BaTiO3 content.