A-site deficient La0.4Sr0.4TiO3-Ce0.9Gd0.1O1.95 composites as efficient and redox stable anodes for solid oxide fuel cells

Abstract

La-doped strontium titanates have attracted much interest as promising reliable ceramic anodes for solid oxide fuel cells (SOFCs) owing to their superior redox-stability. Moreover, recent studies demonstrated that A-site deficiency of the La-doped SrTiO3 perovskite could effectively promote conductivity and catalytic activity, simultaneously. In this study, we developed the LST44-Ce0.9Gd0.1O1.95 (GDC) composite anodes, and investigated their electrochemical performance and redox stability on La0.8Sr0.2Ga0.8Mg0.2O3-delta (LSGM) electrolyte-based SOFCs. During galvanostatic long-term stability tests combined with in situ redox cycles, power out-put performance of the LST44-GDC employed SOFC was initially increased by similar to 53% to 0.26 W cm(-2) and maintained the high performance over 350 h at 800 degrees C. Analysis of the accumulated electrochemical impedance spectra during the long-term stability test showed that the electrochemical activity of the LST44-GDC anode was promoted at the initial redox cycling. Consequently, this study demonstrates that A-site deficient LST44-GDC is a promising material as an efficient and redox stable SOFC anode. (C) 2019 Elsevier B.V. All rights reserved.