纳米复合La9.33Si6O26/Ce0.85Bi0.15O1.925氧离子导电体的制备及其导电性能

将以聚乙烯醇为聚合剂的空间俘获合成法与共沉淀法相结合制备85% La9.33Si6O26-15% Ce0.85Bi0.15O1.925纳米复合氧离子导电体.通过X射线衍射方法分析试样的相组成和晶粒尺寸,利用交流阻抗测试研究材料的氧离子导电性.研究结果表明:所用合成方法能制备La9.33Si6O26 和Ce0.85Bi0.15O1.925两相共存的纳米复合材料,纳米复合粉体的平均晶粒尺寸为35 nm,纳米复合烧结块体材料的平均晶粒尺寸为70 nm;通过纳米复合技术能显著提高材料的氧离子导电性;在600 ℃时,纳米复合材料的氧离子导电性比纯La9.33Si6O26的导电性提高2个以上数量级.

Preparation and conductivity of nano-composite La9.33Si6O26/Ce0.85Bi0.15O1.925 oxygen ionic conductor

85% La_(9.33)Si_6O_(26)/Ce_(0.85)Bi_(0.15)O_(1.925) nano-composite oxygen-ionic conductors were fabricated by combining with the steric-entrapment-synthesis method polymerized by polyvinyl alcohol and the co-precipitation process. The phase component and grain size of the prepared samples were analyzed by X-ray diffractrometry, and the oxide-ionic conductivities were measured by AC impedance measurement. The results show that the nano-composite materials compose of La_(9.33)Si_6O_(26)/Ce_(0.85)Bi_(0.15)O_(1.925) were successfully obtained, the average grain size of the as-calcined powder is 35 nm and the one of as-sintered bulk is 70 nm. The oxide-ionic conductivity is enhanced obviously by nanocomposite technology. The conductivities of nanocomposite increase by two orders in magnitude compared to that of the pure La_(9.33)Si_6O_(26) ceramic at 600 ℃.