Suppressed Sr segregation and performance of directly assembled La0.6Sr0.4Co0.2Fe0.8O3-delta oxygen electrode on Y2O3-ZrO2 electrolyte of solid oxide electrolysis cells
Suppressed Sr segregation and performance of directly assembled La0.6Sr0.4Co0.2Fe0.8O3-delta oxygen electrode on Y2O3-ZrO2 electrolyte of solid oxide electrolysis cells
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固体氧化物电解槽Y2O3-ZrO2电解质上直接组装La0.6Sr0.4Co0.2Fe0.8O3-δ氧电极的Sr偏析抑制及其性能
DOI：
10.1016/j.jpowsour.2018.02.082
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发表时间：
2018
影响因子：
9.2
通讯作者：
Jiang San Ping
中科院分区：
文献类型：
--
作者：
Ai Na;He Shuai;Li Na;Zhang Qi;Rickard William D A;Chen Kongfa;Zhang Teng;Jiang San Ping
活性稳定的氧电极可能是固体氧化物电解电池（SOEC）技术发展中最重要的。在此，我们报道了直接组装在无阻挡层氧化钇稳定氧化锆（YSZ）电解质上的混合离子电子导电（MIEC）La0.6Sr0.4Co0.2Fe0.8O3-δ（LSCF）钙钛矿氧化物的成功开发，作为SOEC的高活性和稳定的氧电极。电解极化有效地诱导电极/电解质界面的形成，类似于在固体氧化物燃料电池（SOFC）运行条件下观察到的情况。然而，与 SOFC 运行条件下显着的性能衰减相比，直接组装 LSCF 氧电极的电池表现出优异的稳定性，并在 SOEC 运行条件下进行了 300hat 0.5Acm−2 和 750°C 的测试。详细的微观结构和物相分析表明，LSCF电极不可避免地会发生Sr偏析，但阳极极化显着抑制了Sr偏析和向电极/电解质界面的迁移，从而在SOEC运行条件下形成稳定高效的电极/电解质界面，用于水和CO2电解。本研究证明了在 SOEC 的无阻挡层 YSZ 电解质上使用直接组装的 MIEC 钴矿基氧电极的可行性。
Active and stable oxygen electrode is probably the most important in the development of solid oxide electrolysis cells (SOECs) technologies. Herein, we report the successful development of mixed ionic and electronic conducting (MIEC) La0.6Sr0.4Co0.2Fe0.8O3-δ(LSCF) perovskite oxides directly assembled on barrier-layer-free yttria-stabilized zirconia (YSZ) electrolyte as highly active and stable oxygen electrodes of SOECs. Electrolysis polarization effectively induces the formation of electrode/electrolyte interface, similar to that observed under solid oxide fuel cell (SOFC) operation conditions. However, in contrast to the significant performance decay under SOFC operation conditions, the cell with directly assembled LSCF oxygen electrodes shows excellent stability, tested for 300 h at 0.5 A cm−2and 750 °C under SOEC operation conditions. Detailed microstructure and phase analysis reveal that Sr segregation is inevitable for LSCF electrode, but anodic polarization substantially suppresses Sr segregation and migration to the electrode/electrolyte interface, leading to the formation of stable and efficient electrode/electrolyte interface for water and CO2electrolysis under SOECs operation conditions. The present study demonstrates the feasibility of using directly assembled MIEC cobaltite based oxygen electrodes on barrier-layer-free YSZ electrolyte of SOECs.