Functionally graded cathodes based on double perovskite type GdBaCo2O5+δ oxide

Large thermal mismatch between GdBaCo2O5+delta (GBCO) oxide and solid electrolytes remains a challenge for its application as a cathode of solid oxide fuel cells (SOFCs). To avoid sharp discontinuities in composition, a functionally graded GBCO cathode is developed, which consists of an inner layer with high electrochemical activity and good thermal compatibility to electrolyte, and an outer layer with high electrical conductivity for current collection. Impedance spectra results reveal that the graded GBCO cathode shows a reduced polarization resistance and more importantly, an improved thermal stability during thermal cycling test. The present work confirms the advantage of graded GBCO cathode that is more robust and reliable for practical application. (C) 2014 Elsevier Ltd. All rights reserved.

钆钡钴氧（GBCO）氧化物与固体电解质之间较大的热失配仍然是其作为固体氧化物燃料电池（SOFCs）阴极应用的一个挑战。为了避免成分的急剧不连续，开发了一种功能梯度GBCO阴极，它由一个具有高电化学活性且与电解质热兼容性良好的内层，以及一个具有高导电性用于收集电流的外层组成。阻抗谱结果表明，梯度GBCO阴极的极化电阻降低，更重要的是，在热循环测试中热稳定性提高。目前的工作证实了梯度GBCO阴极在实际应用中更坚固、更可靠的优势。（C）2014爱思唯尔有限公司。保留所有权利。