利用普适介电理论对银/氧化锌复合材料介电性能的研究

研究了银/氧化锌复合材料的介电特性，发现其在低频下的频率特性表现出很强的弥散现象，直流电导相对真交流电导也不可忽略.利用普适介电理论，对于频率范围为10^-1—10⁷ Hz, 温度范围为173—473 K的实验结果进行了分析.通过对电导率的标准化处理发现，不同银含量的样品其介电损耗机理相同，均属深能级的电子跳跃.试样的电位梯度E_1mA随银含量的变化可以通过α_lf随银含量的变化关系来反映.实验结 关键词： 普适介电理论 介电特性 氧化锌

Study of Ag/ZnO composite material by universal power law

The dielectric properties of Ag/ZnO composite material are investigated and a strong low-frequency dispersion phenomenon is found. The experimental results are systematically studied in the frequency range of 0.1—10⁷ Hz and in the temperature range of 173—473 K. By means of normalization of conductivity, it is found that samples with different Ag contents show similar mechanism of dielectric loss, which is suggested as electron jumping between deep levels. In addition, it is also found that the dependence of E_1mA on Ag content is similar to that of α_lf on Ag content, which is a novel result in the research of varistor materials. The results can be fully understood by means of universal power law.