Giant dielectric permittivity and room temperature magnetodielectric study of BaTi0.2(Fe0.5Nb0.5)0.8O3 nanoceramic

Abstract

BaTi0.2(Fe0.5Nb0.5)0.8O3 [BTFN] ceramic was prepared by sol–gel method. X-ray diffraction pattern of the sample at room temperature shows a cubic phase. Microstructure analysis shows well-grown and dense grains in the sintered sample. High dielectric constant (∼15,000) with low loss (∼0.6) was found at room temperature at 1kHz frequency. Cole–Cole plot analysis shows that the grain boundary effect (barrier layer formation) is responsible for such a high value of dielectric constant. Another interesting feature of BTFN ceramic is the appearance of room temperature high magnetodielectric response (∼8%) at 9kOe magnetic field. Magnetodielectric effect was observed in the sample which is due to the Maxwell–Wagner polarization along with magnetoresistance.