IrO2修饰LSCF阴极对SOFC的影响

通过溶胶凝胶-自燃烧法制备了阴极La0.6Sr0.4Co0.2Fe0.8O3(LSCF)粉体。以NiO-GDC||GDC为阳极和电解质上并在GDC电解质表面,制备了GDC-LSCF复合阴极。采用离子浸渍法在GDC-LSCF阴极内部制备了IrO2功能材料,并比较了在不同温度和浸渍量下燃料电池的输出效果。采用XRD、SEM和电化学工作站等表征方法对该电池和复合阴极进行研究。研究表明通过离子浸渍法在GDC-LSCF复合阴极骨架的表面,形成了大量的IrO2纳米颗粒,该纳米颗粒大幅度增加了三相反应界面的长度。当IrO2浸渍量为0.5 wt%的时候,燃料电池的性能在750℃的功率密度为492 m W·cm^-2,电化学阻抗为1.30Ω·cm^2,该电池表现出较好的性能和较低的阻抗,这与IrO2较好的电子电导和催化活性有关。该电池在中温条件700℃、750℃和800℃的电池功率分别为493 mW·cm^2、581 mW·cm^2、632 m W·cm^2,具有较好的中温操作特性。

Research on the Performance of Impregnated IrO2-LSCF Composite Cathode for Solid Oxide Fuel Cell

La0.6Sr0.4Co0.2Fe0.8O3(LSCF)composite powder was synthesized by sol-gel method and used as a cathode material on NiO-GDC||GDC||LSCF-GDC fuel cell.In order to improve the cathode performance,IrO2 nanoparticles are prepared on the LSCF-GDC backbones by ion-impregnation method.SEM,XRD and EIS are used to observe the microstructure and of the cathodes.The power density of the single cells are 493 mW·cm^2,581 mW·cm^2,632 mW·cm^2 at 700℃,750℃,and 800℃,respectively.Fuel cell performance was improved with addition of 0.5 wt%IrO2 in LSCF-GDC cathode.The nanoparticles are well connected,forming a continuous path for electron conduction.TPB are greatly increased in this IrO2-LSCFGDC,shows a polarization resistance of 1.30Ω·cm^2 which is lower than LSCF-GDC cathode at 750℃.