The effect of sintering temperature on the performance of IT-SOFC SrFe0.9Sb0.1O3- perovskite oxide

Abstract

Abstract. The perovskite cathode material of SrFe 0.9 Sb 0.1 O 3-δ (SFS) was prepared by glycine-nitrate process (GNP). The SFS oxides sintered at 1150，1200 and 1250 ºC for 10 h were crystallized into a single phase perovskite structure, respectively. The effect of sintering temperature on crystal structure, conductivity and polarization resistance was also discussed in detail. The X-ray diffraction and SEM results show that the density increases with the increase of sintering temperature. The results of electrical properties show that the conductivity of SFS samples is dominated by p-type conductivity, and the conduction behavior is in accordance with the mechanism of small polaron jumping. With the rising sintering temperature, the conductivity of prepared samples increases gradually. In the temperature 650−800 ºC, the conductivity values are 57.8−32.5, 63.6−35.8 and 74.5−40.3 S cm −1 for the SFS samples of sintering at 1150, 1200 and 1250 ºC, respectively. The SFS cathode has a good chemical compatibility with the SDC electrolyte at temperatures below 950 °C. The polarization resistances of SFS cathode were 0.064, 0.052 and 0.047 Ω cm 2 at 800 ºC, respectively. The results show that the SFS material of sintering at 1250 °C has promising prospects for the application of IT-SOFCs.

Sr Segregation in Perovskite Oxides: Why It Happens and How It Exists

“…Therefore, there is always a tradeoff between the materials and the manufacturing process when determining the sintering temperature, and many studies have reported change of the electrode or cell performance outcomes according to the sintering temperature. 125,126 Surprisingly, however, none of these prior studies discussed how the sintering temperature affects the degree of Sr segregation and, thus, deterioration of electrode performance. Sintering takes place only for a short time within a few hours at higher temperatures while the operating temperature of the cell is relatively low but lasts for a very long time, possibly under a strong thermodynamic potential gradient.…”