This paper reports on a study of the electrical properties of SnO2-based varistor blocks. The nonlinearity of these ceramics was evaluated based on their voltage-current characteristics, while the height, width and charge carriers were evaluated by impedance spectroscopy and activation energies. The α values were relatively low, with the SCNCrPr system showing the highest value: 6.3. Although the average grain size of the SCNCrLa system was small, i.e., 1.66 μm, its Er value was very low, which may be attributed to the non-formation of effective barriers in the grain boundary region, thus generating a high leakage current in the order of 230 μA.
electrical properties; SnO2; varistors
