(贵州师范学院 贵州省纳米材料模拟与计算重点实验室，贵阳 550018)
摘 要: 本文采用溶液静电纺丝的方法，制备了一种纤维结构阴极材料La0.5Sr0.5CoO3-δ，系统研究了该阴极材料的结构、热稳定性和电化学性能。结果表明：相对于常规粉末材料制备的普通颗粒结构阴极，纤维结构阴极的晶格热稳定性良好，孔隙分布更加均匀合理，电化学性能更加优越。在800 ℃下，纤维结构阴极的界面电阻低至0.035 Ω？cm2，对应单电池的最大输出功率为930 mW/cm2，表现出快速的氧还原反应电极过程动力学；常规多孔结构阴极的界面电阻为0.065 Ω？cm2，对应单电池的最大输出功率仅为750 mW/cm2；在电池的运行过程中，纤维结构阴极的电化学性能也较稳定，在750 ℃和0.6 V恒电位载荷下运行15 h后，电池的输出功率从740 mW/cm2缓慢衰减到660 mW/cm2，表明极化电阻的加剧程度较小。
关键字: 固体氧化物燃料电池；阴极；电化学性能；纤维结构
（Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018, China）
Abstract:A fiber-structured La0.5Sr0.5CoO3-δ cathode was prepared via electrostatic spinning of solution, and the structure, thermal stability, and electrochemical performance of this fiber-structured cathode was systematically investigated. The results show that, compared with the common particle-structured cathode prepared from the plain powder material, this fiber-structured cathode reveals more favorable thermal stability of lattice, more rational pore distribution, and more advanced electrochemical performance. At 800 ℃, the area specific resistance with this fiber-structured cathode is as low as 0.035 Ω？cm2, and the maximum power density with the corresponding single-cell is 930 mW/cm2, showing the fast electrode kinetics of oxygen reduction reaction. Comparatively, the area specific resistance with the common particle-structured cathode is 0.065 Ω？cm2, and the maximum power density with the corresponding single-cell is only 750 mW/cm2. Moreover, in cell operation, the electrochemical performance of this fiber-structured cathode is also very stable, and the output power of cells under a constant loading voltage of 0.6 V at 750 ℃ drops slowly from 740 mW/cm2 to 660 mW/cm2 after 15 h of running, showing the slow worsening of area specific resistance.
Key words: solid oxide fuel cell; cathode material; electrochemical performance; fibrous structure
