The thermal expansion coefficient (TEC) of Co-based layered perovskite electrodes is about twice than that of common electrolytes, and this thermal mismatch between electrode and electrolyte leads to the delamination and cracking of electrode. To solve this problem thoroughly, a strategy of introducing negative thermal expansion (NTE) material is pro-posed. The average linear thermal expansion coefficient of PrBaCo2O5+5 (PBC) decreases significantly from 22.3 x 10-6 K-1 to 12.2 x 10-6 K-1 when compounds with 50 wt NdMnO3-5 (NM). The results of multi physical field coupling calculation show that the introduction of NTE oxide can reduce the residual stress of oxygen electrodes and elec-trolytes, which decreases the trend of electrodes damaged by thermal stress. The com-posite electrode (PBC-NM) shows excellent electrocatalytic activities and reversible cycle performance. The peak power densities (PPDs) of the cell with PBC decreases from 1.4 to 0.48 W cm-2 (65.7 decrease) after 20 thermal cycles, while the one of PBC-NM-based cell decreases from 1.55 to 1.25 W cm-2 (19.4 decrease). Electrochemical impedance spec-troscopy (EIS), scanning electron microscope (SEM) and distribution of relaxation time (DRT) analysis show that the improvement of thermal cycle stability of SOFC can be attributed to the ideal thermal matching between electrolyte and oxygen electrode.(c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
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机译：Co基层状钙钛矿电极的热膨胀系数（TEC）约为普通电解质的2倍，电极与电解液之间的这种热不匹配导致电极分层和开裂。为了彻底解决这一问题，提出了一种引入负热膨胀（NTE）材料的策略。当NdMnO3-5（NM）含量为50 wt%时，PrBaCo2O5+5（PBC）的平均线性热膨胀系数从22.3 x 10-6 K-1显著降低到12.2 x 10-6 K-1。多物理场耦合计算结果表明，NTE氧化物的引入可以降低氧电极和电解液的残余应力，从而减小了电极受热应力损坏的趋势。复合电极（PBC-NM）表现出优异的电催化活性和可逆循环性能。经过20次热循环后，PBC电池的峰值功率密度（PPDs）从1.4 W cm-2降低到0.48 W cm-2（下降65.7%），而PBC-NM电池的峰值功率密度从1.55 W cm-2降低到1.25 W cm-2（下降19.4%）。电化学阻抗谱（EIS）、扫描电子显微镜（SEM）和弛豫时间分布（DRT）分析表明，SOFC热循环稳定性的提高可归因于电解质和氧电极之间理想的热匹配。（c） 2022 Hydrogen Energy Publications LLC.，由爱思唯尔有限公司出版。保留所有权利。
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