Electrochemical performance of La_(0.65)Sr_(0.35)MnO_3 oxygen electrode with alternately infiltrated Sm_(0.5)Sr_(0.5)CoO_(3-δ) and Sm_(0.2)Ce_(0.8)O_(1.9) nanoparticles for reversible solid oxide cells

摘要

La1-xSrxMnO3 is a well-known oxygen electrode for reversible solid oxide cells (RSOCs). However, its poor ionic conductivity limits its performance in redox reaction. In this study, we selected Sm0.5Sr0.5CoO3-5 (SSC) as catalyst and Sm0.2Ce0.8O1.9 (SDC) as ionic conductor and sintering inhibitor to co-modify the La0.65Sr0.35MnO3 (LSM) oxygen electrode through an alternate infiltration method. The infiltration sequence of SSC and SDC showed an influence on the morphology and performance of LSM oxygen electrode, and the influence was gradually weakened with the increasing infiltration time. The polarization resistance of the alternately infiltrated LSM-SSC/SDC electrode was 0.08 Omega cm(2) at 800 degrees C in air, which was 3.36 of the LSM electrode (2.38 Omega cm(2)). The Ni-YSZ/YSZ/LSM-SSC/SDC single cell attained a maximum power density of 1205 mW cm(-2) in SOFC mode at 800 degrees C, which was 8.73 times more than the cell with LSM electrode. The current density achieved 1620 mA.cm(-2) under 1.5 V at 800 degrees C in SOEC mode and the H-2 generation rate was 3.47 times of the LSM oxygen electrode. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.