Double perovskite oxide GdBaCo₂O_5+δ (GBCO) is widely investigated as promising cathode for solid oxide fuel cells (SOFCs), but it remains unclear whether GBCO is suitable for application in solid oxide electrolysis cells (SOECs) anode. In this study, the effect of anodic polarization on electrochemical activity and microstructure of GBCO electrode are investigated under SOECs operation conditions. Both polarization and impedance spectra results clearly demonstrate that anodic bias treatment leads to substantial performance degradation and higher anodic current passage causes more serious activity loss. The deactivation behavior can be mainly ascribed to the formation of surface BaO precipitates in harsh oxidation atmosphere, as revealed by microstructural observation. Our study suggests that GBCO oxide is not suitable for SOECs anode application, but significant change of surface chemistry enables it a good model electrode for segregation related studies.

钙钛矿双氧化物GdBaCo ₂ O _{5 +δ}（GBCO）被广泛研究为固体氧化物燃料电池（SOFC）的有希望的阴极，但尚不清楚GBCO是否适合用于固体氧化物电解电池（SOEC）的阳极。在这项研究中，研究了阳极极化对SOEC操作条件下GBCO电极的电化学活性和微观结构的影响。极化和阻抗谱结果均清楚地表明，阳极偏压处理会导致性能大幅下降，而更高的阳极电流通过率则会导致更严重的活动损失。失活行为主要归因于在苛刻的氧化气氛中表面BaO沉淀的形成，如通过微观结构观察所揭示的。我们的研究表明，GBCO氧化物不适合SOEC的阳极应用，