Liang Fengli, Tseng Po-Hung, Sun Qiang, Li Mengran, Zhou Wei, Liu Lian X, Wang Hao, Zhu Zhonghua
School of Chemical Engineering, the University of Queensland, Brisbane, 4072, Australia.
Centre for Microscopy and Microanalysis, the University of Queensland, Brisbane, 4072, Australia.
J Colloid Interface Sci. 2022 Feb;607(Pt 1):53-60. doi: 10.1016/j.jcis.2021.08.182. Epub 2021 Aug 30.
Mixed electronic and ionic conductivity (MIEC) perovskite oxides hold promise as cathode with high oxygen reduction reaction (ORR) activity for solid oxide fuel cells (SOFCs) operating at reduced temperatures. However, these MIEC cathodes usually contain lanthanide or alkaline-earth elements at A-site. These elements tend to interact with yttria-stabilized zirconia electrolyte (YSZ) to form unwanted phases such as LaZrO and SrZrO at conventional electrode fabrication conditions (>800 °C). Such unwanted interfacial reaction severely degrades the cell performance. We present a new method to assemble SrCoFeWO (SCFW) directly onto YSZ by a highly efficient microwave plasma technique. Intimate contact between SCFW and YSZ phases can be achieved by ten-minute microwave-plasma treatment with no new phase formation. Consequently, the microwave-plasma fabricated interface exhibits a notably high ORR performance, showing an area-specific resistances of 0.11 Ω cm at 600 °C, about two orders of magnitude better than the equivalent prepared via the conventional method. Our method is also effective in assembling other MIEC perovskite cathodes such as SrCoFeO and SrCoNbTaO on YSZ electrolyte, achieving notable enhancement of the cathode performance. This study thus provides an effective and convenient method for synthesizing reactive and robust interfaces between two incompatible phases with minimized interphase interactions.
混合电子和离子传导性（MIEC）钙钛矿氧化物有望作为低温运行的固体氧化物燃料电池（SOFC）中具有高氧还原反应（ORR）活性的阴极。然而，这些MIEC阴极在A位通常含有镧系元素或碱土元素。在传统电极制造条件（>800 °C）下，这些元素倾向于与氧化钇稳定的氧化锆电解质（YSZ）相互作用，形成不需要的相，如LaZrO和SrZrO。这种不需要的界面反应会严重降低电池性能。我们提出了一种通过高效微波等离子体技术将SrCoFeWO（SCFW）直接组装到YSZ上的新方法。通过十分钟的微波等离子体处理，可以实现SCFW和YSZ相之间的紧密接触，且不会形成新相。因此，微波等离子体制备的界面表现出显著的高ORR性能，在600 °C时面积比电阻为0.11 Ω cm，比通过传统方法制备的等效界面好约两个数量级。我们的方法在将其他MIEC钙钛矿阴极，如SrCoFeO和SrCoNbTaO组装到YSZ电解质上也很有效，实现了阴极性能的显著提高。因此，本研究提供了一种有效且便捷的方法，用于合成两个不相容相之间具有最小相间相互作用的活性和坚固界面。
