Influence of thin oxide films obtained from rare-earth nitrate solutions on the electrochemical performance of porous electrodes

Abstract

• SOFC electrodes were impregnated by the solution method in which oxide nanofilms are formed. • The inclusion of nanofilms of some oxides in SOFC electrodes increases their activity. • The polarizing conductivity of the impregnated electrodes correlates with the ambipolar conductivity of the films. • Submicron barrier layers prevent interaction between the electrode and the YSZ electrolyte. The present paper is a review of our research results (obtained at the Institute of High Temperature Electrochemistry) on the electrode reactions at the Pt|YSZ electrolyte (yttria-stabilized zirconia) interface during the impregnation of porous electrodes by some rare-earth oxides (CeO 2-x , PrO x , TbO x ) as well as Tb 1-x Ce x O 2-α mixed oxides. The impregnation was performed in the nitrate solutions of rare-earth elements, in such a way that oxide nanofilms were formed at the surface of the electrolyte. The impact of the submicron barrier Ce 0.8 R 0.2 O 2-a (R = Y, Sm, Tb) films on the polarization resistance of the La 2 NiO 4 |YSZ boundary is studied. A comprehensive review of available literature data is performed.