Structural, Sintering and Electrical Properties of Cr-doped La0.6Sr0.4CrxFe1−xO3−δ (x=0.10, 0.20) Oxides

The perovskite Cr-doped La0.6Sr0.4CrxFe1−xO3−δ (x=0.10, 0.20) oxides were synthesized via the citrate gel method. The perovskite forming of the La0 6Sr0.4CrxFe1−xO3−δ (x=0.10, 0.20) oxides were studied by thermogravimetric analysis (TG), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Structural and chemical stability under H2-containing helium atmospheres of La0.6Sr0.4CrxFexO3−δ (x=0.10, 0.20) were investigated by TG and XRD. The sintering microstructures of the perovskite La0.6Sr0.4CrxFexO3−δ (x=0.10, 0.20) ceramics were investigated by scanning electron microscopy (SEM), and the electrical conductivities of both oxide ceramics were also measured up to 900 °C. The results demonstrated that the chemical stability of the Co-free La0.6Sr0.4CrXFe1−XO3−δ (x=0.10, 0.20) oxides was significantly improved compared to the Co-containing La0.6Sr0.4Co0.2Fe0.8O3−δ and Ba0.5Sr0.5Co0.8Fe0.2O3−δ oxides. The incorporation of Cr cations in the B-site of the pervoskite oxides resulted in the improved structural and chemical stability of the as-synthesized La0 6Sr0.4CrxFe1−XO3−δ (x=0.10, 0.20) oxides.