反応性添加物を用いたSOFC空気極のガラス質不純物への耐性の向上に関する研究

快速氧交换动力学是固体氧化物燃料电池（SOFC）电极的一个关键品质指标，即使是很小浓度的杂质也会严重阻碍其性能。例如，Si在陶瓷加工中很常见。结果发现，氧交换动力学的快速降解发生在致密的薄膜的Pr0.1Ce0.9O2-d（PCO），混合离子电子导电电极的SOFC。一种新的光透射弛豫（OTR）技术的开发，以帮助在裸膜表面上的动力学测量。这种技术的一个关键优点是它不需要传统测量中典型的集电器。通过TEM和XPS确定Si是重要的表面杂质，其在电极表面上形成阻挡层。发现沉积的La氧化物膜导致在测量的样品上的氧交换动力学的完全恢复。La和Si氧化物被发现相互作用，确定在O 1 s XPS峰的位移和系统的OTR研究的薄膜，可能与Si（如La，Sm氧化物）和那些不（如Nb，Ti，Zn氧化物）。这些结果表明，La可以“清洁”SOFC电极的表面，从而显著改善氧传输动力学。对La-PCO固溶体的OTR的初步测量表明改善的长期电极动力学稳定性，证明了该方法实现Si杂质耐受性的商业潜力。

Fast oxygen exchange kinetics, a key figure of merit in solid oxide fuel cell (SOFC) electrodes, is often dramatically hindered by the presence of even small concentrations of impurities. Si, for example, is common in ceramics processing. It was found that rapid degradation of oxygen exchange kinetics occurred on dense thin films of Pr0.1Ce0.9O2-d (PCO), a mixed ionic electronic conducting electrode for SOFCs. A new optical transmission relaxation (OTR) technique was developed to aid in measuring kinetics on the bare film surfaces. A key advantage of this technique is that it does not require current collectors typical of conventional measurements. Si was identified by TEM and XPS as a significant surface impurity, which forms a blocking layer on the electrode surface. Deposition of a La oxide film was found to result in full recovery of oxygen exchange kinetics on the measured sample. La and Si oxides were found to interact with each other as identified by a shift in the O1s XPS peak and a systematic OTR study of films that likely react with Si (e.g. La, Sm oxides) and those that do not (e.g. Nb, Ti, Zn oxides). These results indicate that La may "clean" the surface of the SOFC electrode, thereby dramatically improving oxygen transport kinetics. Preliminary measurements of OTR on a La-PCO solid solution indicates improved long-term electrode kinetics stability, demonstrating the commercial potential of this method to achieve Si impurity tolerance.