Influence of ZnSb₂O₆ Doping on Phase, Electrical and Dielectric Properties of ZnO Varistors

The present investigation reports the variations of the microstructure and electrical properties due to a change in the ZnSb 2 O 6 content of ZnO varistors. The impact of the ZnSb 2 O 6 additive on both microstructure and electrical properties in ZnO varistors is studied via the X‐ray diffraction (XRD) and an impedance analyzer. Zn 7 Sb 2 O 12 spinel phase and single hexagonal ZnO phase are detected in ZnO varistors with the addition of ZnSb 2 O 6 . The ZnO varistors with 5 mol% ZnSb 2 O 6 have the highest nonlinear coefficient (43.2) and the lowest leakage current density (3.96 A cm −2 ). The resistivity of grain boundary ρ gb increases continuously with the increasing content of ZnSb 2 O 6 as demonstrated by impedance measurements. Additionally, low values of dielectric loss at high frequencies suggest a ZnO varistor doped with ZnSb 2 O 6 is suitable for high frequency device applications.