Understanding equilibrium and non-equilibrium dopant segregation towards more stable electrode materials

作为该研究项目的一部分，我们一直在研究界面对固体氧化物燃料电池（SOFC）和固体氧化物电解槽电池（SOEC）先进组件开发的影响。我们证明了点缺陷的数量，这是至关重要的阴离子和阳离子的扩散，可以操纵在界面处经常存在于电极的SOEC/SOFC设备。通过制造原型电极材料的纳米结构，我们能够调整氧空位的浓度，从而调整输运性质。此外，还证明了通过控制薄膜系统中存在的晶格应变，可以操纵这些缺陷的迁移率作为应变、迁移方向和缺陷-缺陷相互作用的函数。最后，已经表明，混合离子电子传导材料（固体氧化物燃料电池电极的潜在候选物）的表面交换可以通过将二元氧化物渗透到表面上而被改性高达7个数量级。有趣的是，表面交换的变化与渗透氧化物的酸度直接相关。

As part of this research project, we have been investigating the effects of interfaces for the development of advanced components for solid oxide fuel cells (SOFCs) and solid oxide electrolyser cells (SOECs). We demonstrated that the number of point defects, which is critical for both anion and cation diffusion, can be manipulated at interfaces often present in electrodes for SOEC/SOFC devices. By fabricating nanostructures of proto-typical electrode materials, we were able to tailor the concentration of oxygen vacancies and, therefore, the transport properties.Furthermore, it was demonstrated that by controlling the lattice strain present in thin film systems, the mobility of such defects could be manipulated as a function of strain, migration direction, and defect-defect interactions.Finally, it was shown that the surface exchange of a mixed-ionic electronic conducting material, a potential candidate for solid oxide fuel cell electrodes, could be modified by up to seven orders of magnitude by infiltrating binary oxides onto the surface. Interestingly, the change in surface exchange was directly correlated to the acidity of the infiltrated oxide.