IMF2017

YBiO₃ has recently attracted the scientific community due to its novel properties such as high ionic conductivity, excellent photo-catalytic behavior and electrolyte material for solid oxide fuel cells. In this work, pristine and La doped YBiO₃ (YBi_1-xLa_xO₃ (0.00 ≤ x ≤ 0.05)) samples were successfully synthesized through co-precipitation. The phase purity of the synthesized samples has been confirmed by XRD measurements. All the samples were found in FCC structure; Rietveld refinements of the series YBi_1-xLa_xO₃ (0.00 ≤ x ≤ 0.05) samples show that the lattice parameter varies from 5.42 Å to 5.46 Å as x changes from 0 to 0.05. The Raman spectrum of YBi_1-xLa_xO₃ (0.00 ≤ x ≤ 0.05) samples revealed the existence of all five Raman active modes of fluorite structure, in agreement with XRD data. From the scanning electron micrographs it is evident that there is a continuous increase in grain size with increasing lanthanum concentration (from ~ 1 μm (for x = 0) to ~ 10 μm (for x = 0.05)). The temperature dependent dielectric spectra reveal a relaxation above 550 °C in YBO. The relaxation temperature reduces to ~400 °C for x = 0.05. Further, dielectric measurements show that the value of dielectric constant enhanced with lanthanum incorporation. The impedance spectroscopy measurements confirmed that the observed relaxation is of the non-Debye type and that the resistance increases with increase in temperature. The contribution of grains and grain boundary in resistance is also understood.