Effects of Zr dopant and sintering temperature on electrical properties of In2O3-SrO based ceramics

Electrical properties of indium oxide ceramics doped by Sr and Zr and sintered at 1473 and 1573 K in air were studied and are discussed. In2O3-SrO ceramics exhibit nonlinear current-voltage behavior with the current limiting effect: current rises more weakly than voltage, is saturated and even decreased. The Zr dopant changes the type of current-voltage dependency in such materials. In2O3-SrO-ZrO2 ceramics with low Zr content (5-10 wt% ZrO2 in mixture) possess linear current-voltage characteristic and very high conductivity. For ceramics with high content of Zr (60 wt% ZrO2 in mixture) the current-voltage dependency is superlinear (current is increased stronger than voltage) but the current limiting effect is not observed. Based on the data of dc and ac measurements, temperature dependence of conductivity, X-ray diffraction, and scanning electron microscopy results, the conductivity features of obtained materials are discussed.