Synthesis of fuel cell grade Bi2Co0.1V0.9O5.35 solid electrolyte thin films

Oxygen ion conducting solid electrolyte thin film of BIMEVOX family Bi2Co0.1V0.9O5.35 was synthesized by an innovative and cost effective spray pyrolysis technique on alumina substrate. The uniformity in deposition is obtained by propane-2ol assisted atomization. Thermal decomposition behavior of precursors was studied using thermogravimetric analysis (TGA and DTA). The room temperature stabilized pure γ-phase Bi2Co0.1V0.9O5.35 was obtained by annealing films at 750 deg. C. The phase of the material is confirmed by XRD. The morphological studies were done using SEM. DC electrical conductivity measurements were done with respect to temperature to reveal the onset for ionic conduction and it was found to be about 420 deg. C. The AC conductivity measurements were also done using impedance spectroscopy in the frequency range 100 Hz to 1 MHz and in temperature range 228-550 deg. C. The ionic conductivity was found to be increasing with temperature. It was of the order of 21.16 S m-1 at 550 deg. C. The single semicircular complex impedance plot shows that the ionic conduction is through grain interior hopping mechanism. The activation energy in high-temperature region was found to be 0.36 eV which is lower than other methods of synthesis. Which is very much favorable for usage of these films in low-temperature solid oxide fuel cells