Structural,Sintering and Electrical Properties of Cr-doped La_(0.6)Sr_(0.4)Cr_xFe_(1-x)O_(3-δ)(x=0.10,0.20) Oxides
【摘要】: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 H 2-containing helium atmospheres of La0.6Sr0.4CrxFe1-xO3-δ(x=0.10,0.20) were investigated by TG and XRD.The sintering microstructures of the perovskite La0.6Sr0.4CrxFe1-xO3-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.