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- ba...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.展开更多
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).
文摘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.
