TRANSPORT PROPERTIES OF CERIUM OXIDE DOPED IN GADOLINIUM USED FOR ELECTRICAL BATTERIES MANUFACTURE

Abstract

In engineering practice, solid electrolyte fuel cells are an increasingly considered alternative for the generation of clean energy, but the high operating temperatures required (800°C - 1000°C) can be an obstacle to commercialization. So, there is research on materials that can be used at lower temperatures. To reduce potential losses, it is necessary to find an electrolyte having good ionic conductivity and low electronic conductivity. Doped cerium oxide is strongly considered as a replacement for yttrium oxide stabilized zirconium oxide, that it is used frequently. It is important to know its electrical properties before using it in a commercial automotive battery. Different compositions of doped cerium oxide have been studied: 10% and 20% doping with gadolinium. Cerium oxide can be doped with different materials, such as: samarium and gadolinium as well as lanthanum and yttrium. This oxide presents, at low temperatures, a higher conductivity than zirconia (ZrO₂ - 10 mols % Y₂O₃), which permits the operating temperature of electrochemical batteries to lower. In this paper the elaboration of polycrystals of cerium oxides doped in gadolinium and their electrical characterization were presented.