Synthesis and Characterization of Fine Grained High Density La_2Mo_2O_9-based Oxide-ion Conductors  

作　　者：Jianxin WANG Qin WANG Xianping WANG Chun LI Qianfeng FANG 

机构地区：[1]Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China [2]Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315040, China

出　　处：《Journal of Materials Science & Technology》2008年第5期761-765,共5页材料科学技术（英文版）

基　　金：the National Natural Science Foundation of China(Grant No.50672100);the Anhui Provincial Natural Science Foundation,China(Grant No.050440901);the Ningbo Civic Natural Science Foundation,China(Grant No.2006A610057).

摘　　要：A cost-efFective technique, including nanocrystalline powder preparation using a modified Pechini method and a two-step low-temperature sintering route, was developed for the synthesis of high performance La2Mo2O9- based oxide-ion conductors. The optimum parameters of the compaction pressure, the first step and ＇the second step sintering temperatures for the synthesis of fine grained, high density and uniform La2Mo2O9- based oxide-ion conductors were determined by a series of sintering experiments. High density and uniform sintered La2Mo2O9 samples with average grain size from 0.8 to 5 μm and La1.96K0.04Mo2O8.96 sample with average grain size as small as 500 nm were synthesized by using this cost-efFective method. The impedance measurement results show that the as-fabricated La2Mo2O9-based ceramics possess much higher ionic conductivity than that obtained by solid state reaction method. It is found that in the range of 0.8-5μm the grain size of dense La2Mo2O9 samples prepared from the nanocrystalline powders has little influence on their conductivities.A cost-efFective technique, including nanocrystalline powder preparation using a modified Pechini method and a two-step low-temperature sintering route, was developed for the synthesis of high performance La2Mo2O9- based oxide-ion conductors. The optimum parameters of the compaction pressure, the first step and ＇the second step sintering temperatures for the synthesis of fine grained, high density and uniform La2Mo2O9- based oxide-ion conductors were determined by a series of sintering experiments. High density and uniform sintered La2Mo2O9 samples with average grain size from 0.8 to 5 μm and La1.96K0.04Mo2O8.96 sample with average grain size as small as 500 nm were synthesized by using this cost-efFective method. The impedance measurement results show that the as-fabricated La2Mo2O9-based ceramics possess much higher ionic conductivity than that obtained by solid state reaction method. It is found that in the range of 0.8-5μm the grain size of dense La2Mo2O9 samples prepared from the nanocrystalline powders has little influence on their conductivities.

关 键 词：Oxide ion conductor La2MoO9 NANOCRYSTALLINE Two-stage sintering 

分 类 号：TB30[一般工业技术—材料科学与工程]