Synthesis and Studies of High-Temperature Electrical Properties of Pb0.8Bi0.2Fe0.734W0.266O3 Solid Solution

The Pb0.8Bi0.2(Fe0.734W0.266)O3 (PBFW) high temperature ceramic has been successfully synthesized by the modified columbite method. The phase purity was confirmed by the room temperature X-ray diffraction measurement and it confirms the formation of cubic structure with Pm-3m space group. The lattice parameters were obtained from the Rietveld refinement technique; with a = b = c = 3.9750 Å. From the Scanning Electron Micrograph; the average grain size were measured about 1 µm and the Gaussian distribution showed uniform distribution of particles with small amount of porous nature. Temperature-dependent ferroelectric (P-E loop) measurement confirms the presence of polar Nanodomains along with leaky behavior owing to the conducting nature of the sample. A detailed study of frequency dependent permittivity and loss tanδ evidenced the Maxwell-Wagner type of polarization. The Non-Debye type of relaxation in the PBFW was confirmed by analyzing the Impedance spectra and fitting the Kohlraush-Williams-Watt function to the electric modulus at few selected temperatures. The impedance spectra reveal that the grain boundaries are more resistive than grains. By fitting the Johnscher's power law to the ac conductivity and from the ‘n' value; we conclude that the system has Correlated Barrier Hopping (CBH) conduction mechanis