氧化铜陶瓷的高介电性

Dielectric Properties of Copper(Ⅱ) Oxide Ceramics

采用固相反应法制备了氧化铜(CuO)陶瓷,得到不同频率下样品的介电随温度变化关系。通过X射线衍射图谱确定CuO陶瓷为单斜相结构,形成了粒径大约为150 nm的晶粒。假定晶粒为被绝缘晶界隔离的半导体,通过cole-cole图得到静态介电常数和高频介电常数,运用Arrhenius关系计算出激活能,进而利用Maxwell-Wagner机制进行理论拟合,与试验结果进行对比分析,表明CuO陶瓷晶粒在低频段、低温区时具有半导体性。

CuO ceramics were prepared by the traditional solid-state reaction method.The dielectric-temperature spectrum were acquired in various frequencies.All the observed peaks can be indexed with the monoclinie phase of CuO.The grain size is about 150 nm.It is accorded with internal barrier layer capacitance model that CuO ceramics consist of semiconducting grains with insulating grain boundaries.The static dielectric constant and high frequency dielectric constant are obtained by Cole-Cole curve.The activation energy is obtained by the Arrhenius relation.The theoretical curves are nearly consistent with the experimental curves, indicating that the dielectric properties of CuO belong to Maxwell-Wagner type.The grain in CuO ceramics is semiconductor in low temperature region and lower frequency.