Enhancing Electrical Characteristics of ZnO-based Varistors through TiO2 Doping

ZnO-based varistors are frequently employed in voltage surge mitigation applications due to their distinctive nonlinear current-voltage properties. The addition of TiO2 to ZnO varistors has been found to increase their electrical characteristics, such as the nonlinear coefficient and breakdown voltage. A theoretical investigation is undertaken in this work to evaluate the impact of TiO2 on the electrical properties of ZnO-based varistors. The findings reveal that TiO2 can operate as a pinning agent, inhibiting ZnO grain development and improving varistor uniformity. As a result, the nonlinear coefficient and breakdown voltage of the varistor rise. Furthermore, TiO2 can form secondary phases with ZnO, which can improve the electrical characteristics of the varistor even further. The results of this study provide a theoretical understanding of the effects of TiO2 on the electrical characteristics of ZnO-based varistors, and they can be used to design varistors with improved electrical properties.