J Mater Sci Technol ›› 2008, Vol. 24 ›› Issue (05): 761-765.

• Research Articles • Previous Articles     Next Articles

Synthesis and Characterization of Fine Grained High Density La2Mo2O9-based Oxide-ion Conductors

Jianxin WANG, Qin WANG, Xianping WANG, Chun LI, Qianfeng FANG   

  1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China
  • Received:2007-04-30 Revised:2007-06-27 Online:2008-09-28 Published:2009-10-10
  • Contact: Qianfeng FANG

Abstract: 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{5 μm the grain size of dense La2Mo2O9 samples prepared from the nanocrystalline powders has little influence on their conductivities.

Key words: Oxide ion conductor, La2Mo2O9, Nanocrystalline, Two-stage sintering