Mixed Conduction in Tb2O3 Doped BaCeO3

✍ Scribed by Li-Gan Qiu; Gui-Lin Ma

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 135 KB
• Volume: 24
• Category: Article
• ISSN: 0256-7660
• DOI: 10.1002/cjoc.200690293

✦ Synopsis

Abstract

Ba~x~Ce~0.8~Tb~0.2~O~3−α~ (x=0.98–1.03) solid electrolytes were synthesized and characterized by using X‐ray diffraction (XRD). By using AC impedance spectroscopy and gas concentration cell electromotive force (EMF) measurements, the electrical conduction behavior of the specimens was investigated in different gases during 500–1000 °C. The influence of nonstoichiometry in the specimens with x≠1 on conduction properties was studied and compared with that in the specimen with x=1. The results show that the specimens are all of perovskite‐type orthorhombic structure. In 500–1000 °C, electronic hole conduction is dominant in dry and wet oxygen, air or nitrogen. Protonic conduction is dominant in wet hydrogen and it is about two orders of magnitude higher than that in hydrogen‐free atmospheres (oxygen, air and nitrogen). The electrical conductivity of the same specimen in water vapor‐saturated oxygen, air or nitrogen is slightly higher than that in corresponding gas without water vapor. The electrical conductivities of the nonstoichiometric specimens are higher than those of the stoichiometric one.