中文摘要：

为研究CuO掺杂对ZnO基压敏陶瓷中的电子密度和电性能的影响,以固相反应法制备了CuO掺杂的ZnO Bi2 O3 Sb2 O3 Co2 O3 MnO2 Cr2 O3基压敏陶瓷,测量了其正电子湮没寿命谱及电性能,结果表明,随着CuO含量的增加,ZnO基压敏陶瓷基体（晶粒内部）和晶界缺陷态的自由电子密度降低,导致其压敏电压V1mA和漏电流I L升高,非线性系数a减小。CuO含量为1.0%的ZnO基压敏电阻可用于220 V交流电路的过压保护。

英文摘要：

In order to study the effects of CuO dopant on electron density and electrical properties of ZnO-based varistor ceramics, the CuO doped ZnO Bi2 O3 Sb2 O3 Co2 O3 MnO2 Cr2 O3 varistor ceramics were prepared by means of the solid state reaction method, and the positron lifetime spectra and electrical properties of the varistor ceramics were measured. The experimental results show that the electron densities in the bulk and on the grain boundaries decrease with the CuO content in the ZnO-based varistor increasing, resulting in the increase of threshold voltage （ V1mA ） and leakage cur-rent （IL） , and the decrease of nonlinear coefficient （a） of the ZnO-based ceramics. The ZnO-based varistor ceramic with 1.0% CuO can be used to the overvoltage protection in a 220 V AC source circuit.