Phase structure and oxygen permeability of partially B-site-substituted BaCoxFe1−xO3−δ ceramic membranes

• Published in: Journal of materials research 2023-03, Vol.38 (5), p.1186-1196
• Main Authors: Pei, Yujie, Xia, Yuanyu, Wang, Yusheng, Li, Fang, Li, Qiming
• Format: Article
• Language: English
• Subjects: Applied and Technical Physics; Biomaterials; Chemistry and Materials Science; Commentary; Comparative studies; Doping; High temperature; Inorganic Chemistry; Low temperature; Materials Engineering; Materials research; Materials Science; Nanotechnology; Optimization; Oxygen; Permeability; Perovskite structure; Perovskites; Phase transitions; Room temperature; Solid phases; Structural stability
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-022-00889-4

Effect of Co dopant on phase structure and oxygen permeability of BaFeO 3− δ hexagonal composite was explored via comparative studies. It demonstrated that the introduction of Co can induce hexagonal BaFeO 3− δ to transform into a cubic perovskite structure. Especially, the partial substitution of Fe with Co by 10–50% can lead to the stabilization of pure cubic perovskite structure even at room temperature. We demonstrated that the improvement in cobalt doping content can increase the lattice volume and oxygen permeability of BaCo x Fe 1− x O 3− δ ( x  = 0.1–0.5) due to appropriate structural optimization. Amongst BaCo x Fe 1− x O 3− δ ( x  = 0.1–0.5) samples, BaCo 0.4 Fe 0.6 O 3− δ displays an excellent oxygen permeability and structural stability owing to optimal Gold Schmidt tolerance factor. Although BaCo 0.5 Fe 0.5 O 3− δ display the highest oxygen permeation flux at elevated temperature, its moderate-low temperature oxygen permeability below 750 °C is poor due to structural phase transition. This study clarifies an optimal doping range of Co cations in BaCo x Fe 1− x O 3− δ  to stabilize their cubic perovskite structure. Graphical abstract