Structure, nonstoichiometry, sintering and oxygen permeability of perovskite SrCo_(1-2x)(Fe,Nb)_xO_(3-δ) (x = 0.05,0.10) oxides

摘要

The novel Fe/Nb co-substituted SrCo_(1-2x)(Fe,Nb)_xO_(3-δ) (x = 0.05, 0.10) oxides have been synthesized and characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetry (TG), and scanning electron microscopy (SEM). The XRD and DSC results demonstrate that the structural stability of the Fe/Nb co-substituted samples x = 0.05, 0.10 is improved greatly compared to the sample x = 0.00. The Fe/Nb co-doping in the SrCoO_(3-δ) oxide results in the improved structural stability of the SrCo_(1-2x)(Fe,Nb)_xO_(3-_δ)s (x = 0.05,0.10) oxides. The nonstoichiometric and sintering properties were investigated by TG and SEM, and the oxygen permeation fluxes were measured at 800-950 C for the sample x = 0.10. The improved oxygen permeability of the ceramic SrCo_(1-2x)(Fe,Nb)_xO_(3-δ)(x = 0.10) membrane compared to the (Ba_(0.5)Sr_(0.5))(Co_(0.8)Fe_(0.2))O_(3-δ) and SrCo_(0.8)Fe_(0.2)O_(3-δ) membranes, was observed under an air/He oxygen partial pressure gradient at 800-950 C.