Synthesis and characterization of cobalt-free SrFe_0·8Ti_0·2O_3-δ cathode powders synthesized through combustion method for solid oxide fuel cells

Cobalt-free SrFe_0·8Ti_0·2O_3-δ cathode powders were synthesized through the combustion method. Results of thermogravimetric and Fourier transform infrared analyses suggested that a perovskite oxide started to form at temperatures above 1100 °C. X-ray diffraction and Rietveld refinement analyses confirmed that the single-phase cubic structure (Pm-3m) of the SrFe_0·8Ti_0·2O_3-δ cathode was produced after calcination at 1300 °C. The average sizes of the particles were 1.0827 and 1.4438 μm as revealed by field emission scanning electron microscopy and dynamic light scattering analysis, respectively. In addition, energy dispersive X-ray analysis coupled with mapping revealed the homogeneous distribution of elements in the cathode. The thermal expansion coefficient of the SrFe_0·8Ti_0·2O_3-δ cathode is 16.20 × 10⁻⁶ K⁻¹. For the electrochemical behavior, the area specific resistance of cathode (0.60–13.57 Ω cm²) was obtained at 600–800 °C, and the activation energy was 121.77 kJ mol⁻¹. This work confirmed the potential of a SrFe_0·8Ti_0·2O_3-δ cathode in the intermediate temperature solid oxide fuel cell.