Coprecipitation preparation and voltage sensitive characteristics of doped ZnO varistor

Abstract

A process of preparing ZnO voltage-sensitive ceramics doped with some oxides by coprecipitation was described in the paper. The thermal properties of ZnO nanometer powders and the current-voltage characteristics of the ceramics have been investigated. The results showed that the six-additive ZnO powders with hexagonal system were homogeneous grain size distribution in microstructure, the optimal reaction pH is 6.90±0.05, the temperature for calcining and sintering was at about 500 °C and 1100 °C, respectively. The powders were also examined by SEM, IR and XRD etc, and the effect of doping La₂O₃ on the electrical properties of ZnO varistor was investigated too.

Keywords

zinc oxide ceramics / coprecipitation / voltage-sensitive / multi-component doping

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