Effect of Dy2O3 and La2O3 on the microstructure and electrical properties of WO3 ceramics
Effect of Dy2O3 and La2O3 on the microstructure and electrical properties of WO3 ceramics
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DOI：
10.1016/j.matchemphys.2005.09.011
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发表时间：
2006-08
影响因子：
4.6
通讯作者：
Xinsheng Yang;Yu Wang;Yong Zhao
中科院分区：
文献类型：
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作者：
Xinsheng Yang;Yu Wang;Yong Zhao
采用传统陶瓷工艺制备了Dy2O3和La2O3掺杂的WO3陶瓷，并对其显微结构、相结构和电学性能进行了研究。Dy掺杂样品中存在多孔片状材料，La掺杂样品中存在棒状材料。人们认为，片状材料（富Dy相）是具有弱导电性的非晶，以形成肖特基势垒。然而，棒状材料（富La相）是具有良好导电性的结晶状态，使得势垒被击穿，导致接近线性的电流-电压特性。晶界势垒层电容器（GBBLC）模型不能解释La掺杂样品的高介电常数，因为晶界材料具有良好的导电性。高介电常数被认为是由晶界中的富La相的高介电极化引起的。
Dy2O3and La2O3-doped WO3ceramics were fabricated by conventional ceramic technique and the microstructure, phase structure and electrical properties were studied. There are some porous slice-shaped materials in Dy-doped samples and club-shaped materials in La-doped samples. It is believed that slice-shaped materials (Dy-rich phase) are amorphism with weak conductivity to form the Schottky barrier. However, club-shaped materials (La-rich phase) are crystalline state with good conductivity so that the barrier is broken down, leading the nearly linear current–voltage characteristics. The grain boundary barrier layer capacitor (GBBLC) model cannot account for the high dielectric constant of La-doped sample because of the good conductivity of grain boundary materials. The high dielectric constant is assumed to arise from the high dielectric polarization of La-rich phase in the grain boundary.