Structural And Microstructural Study Of La0.5Sr0.5 Bi 0.2Co0.5Fe0.3O3-? Cathode Ceramic For Intermediate Temperature Solid Oxide Fuel Cells

Abstract

A cost effective flash pyrolysis method has currently been used to prepare
highly pure and nano-sized La0.5Sr0.5Bi0.2Co0.5Fe0.3O3-? cathode ceramic powder for
intermediate temperature solid oxide fuel cells (IT-SOFCs). La0.5Sr0.5Bi0.2Co0.5Fe0.3O3-?
ceramic powder and sintered pellets has been characterized through X-ray Diffraction
(XRD), Field Emission Scanning Electron Microscopy (FESEM) and High Resolution
Transmission Electron Microscopy (HRTEM). The XRD pattern of
La0.5Sr0.5Bi0.2Co0.5Fe0.3O3-? ceramic sintered at 700 °C for 4 h exhibits the pure
rhombohedral phase having R3C space group symmetry. Rietveld refinement has been
done to extract unit cell parameters and bond length using the XRD pattern of
La0.5Sr0.5Bi0.2Co0.5Fe0.3O3-? ceramic sintered at 700 °C for 4 h. The average particle size of
the powder calcined at 600 °C is found to be 22.3 nm through HRTEM investigation. The
microstructure of fracture surface of La0.5Sr0.5Bi0.2Co0.5Fe0.3O3-? sintered pallet at 700 °C
for 4 h reveals fine bimodal type gains and porous nature with 35.89 nm average grain size
through FESEM analysis