摘要
采用甘氨酸-硝酸盐（GNP）法制备了La0．6Sr0．4Co1-yFeyO3（y=0．2，0．8）g合氧化物，研究了材料的结构、电子-离子混合导电性能及其相关性。结果表明，La0.6Sr0.4Co1-yFeyO3（y=0．2，0．8）合成粉料的颗粒细小均匀（～100nm），陶瓷形成菱形六面体钙钛矿结构。与La0．6Sr0．4Co0．2Fe0．8O3（y=0．8）陶瓷相比，La0.6Sr0.4Co0．8Fe0．2O3（y=0．2）陶瓷的晶粒尺寸大、致密度较高。在La0.6Sr0.4Co0．8Fe0．2O3（y=0．2）陶瓷中观察到Co^3＋离子歧化对电子导电性能的影响。与La0.6Sr0.4Co0.2Fe0.8O3（y=0．8）陶瓷相比，La0.6Sr0.4Co0.8Fe0．2O3（y=0．2）陶瓷具有更优异的电子-离子混合导电性能，材料在混合导电性能上的差异与其电子结构和显微结构紧密相关。
La0.6Sr0.4Co1-yFeyO3（y = 0.2, 0.8） powders were synthesized by a glycine-nitrate process （GNP）, and the structure and mixed electronic-ionic conducting properties of the resuhing ceramics were investigated. The synthesized La0.6Sr0.4Co1-yFeyO3 （y = 0.2, 0.8） powders have a pure perovskite structure and consist of uniform and fine particles （ ～ 100 nm）. A pure perovskite structure with rhombohedral symmetry is identified for La0.6Sr0.4 Co1-y FeyO3 （ y = 0.2, 0.8） ceramics. Compared with La0.6Sr0.4Co0.2Fe0.8O3 （y = 0. 8） ceramics, La0.6Sr0.4Co0.8Fe0.2O3 （y = 0. 2）ceramics show a denser microstructure and larger grains. A contribution of charge disproportionation of Co^3＋ to the electronic conducting properties is observed for La0.6Sr0.4Co0.8Fe0.2O （y = 0.2） ceramics. La0.6Sr0.4Co0.8Fe0.2O3 （y = 0.2） ceramics exhibit superior mixed electronic-ionic conducting properties than La0.6Sr0.4Co0.2Fe0.8O3 （y = 0.8） ceramics. It is considered that the difference in the mixed conducting properties between the two compositions can be interpreted with respect to their electronic structure and microstructure.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2006年第4期503-506,共4页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金资助项目(50572079)
教育部新世纪优秀人才支持计划(NECT-04-0724)
教育部博士点科研专项基金项目(20030497008)资助
