Electrical Behavior of Ceria‐Stabilized Zirconia with Rare‐Earth Oxide Additives

Abstract

The electrical properties of rare‐earth oxide doped CeO 2 ‐ZrO 2 ceramics are evaluated by impedance spectroscopy. Doping of the trivalent metal oxide decreases both the grain and grain‐boundary resistivities of the CeO 2 ‐ZrO 2 system. The grain and grain‐boundary resistivities as well as the activation energy for conduction increase with the dopant cation radius. The grain conductivity is fairly constant for 2 mol% YO 1.5 ‐10 mol% CeO 2 ‐88 mol% ZrO 2 samples sintered under different conditions, while lower grain‐boundary resistivity is obtained for samples sintered at higher temperature for longer times. Possible mechanisms for the electrical behavior of the rare‐earth oxide doped CeO 2 ‐ZrO 2 ceramics are proposed and discussed.