Influence of additives on the electrical properties of dense SnO2-based ceramics

Abstract
Highly densified 0.99 SnO2‐0.01 CuO‐based ceramics with antimony, tantalum, or niobium oxides as additives have been prepared. Samples have been characterized by dc conductivity and complex impedance spectroscopy as a function of temperature and by current density as a function of electric field. Microstructures have been analyzed by scanning electron microscopy, electron microprobe, and Auger spectroscopy. The electrical properties of Ta‐ and Nb‐doped ceramics are grain boundary controlled at least at low temperature. Sb‐doped materials show a different electrical behavior due to the presence of a segregation layer of antimony which inhibits grain boundary effects.