Synthesis and ionic transport phenomena of Ca doped Bi₂O₃

Bismuth oxide based materials are commonly used in modern ferroelectrics, multi-ferroics, gas sensors, light photo catalysts and fuel cells. In this work, we report comparative study of synthesis, optical and electrical properties of nano crystalline Calcium doped Bismuth Oxide synthesized by citrate auto ignition method and sintered at different temperatures. The formation of nano crystalline Ca doped Bi₂O₃ was confirmed from X-ray diffraction pattern analysis of the samples which indicate the single rhombohedral phase of the prepared materials. Lattice parameters, crystallite size and lattice strain values were obtained using Rietveld analysis of the XRD profiles. UV-VIS spectroscopy studies have been employed for investigation of optical properties of these samples. Presence of different molecular bonds was confirmed using FT-IR spectroscopy. Electrical data were recorded using a LCR meter in the frequency range 42 Hz to 5 MHz and in the temperature range RT to 450 °C. The electrical data were analyzed using impedance spectroscopy. It was observed that the ionic conductivity of all the samples increased with increase in temperature. Detailed analysis of the obtained results will be reported in the presentation. (author)