Pr_(0.8)Sr_(0.2)Fe_(0.7)Ni_(0.3)O_(3-δ)-Pr_(1.2)Sr_(0.8)Ni_(0.6)Fe_(0.4)O_(4+δ)复合阴极的制备及其电化学性能

Preparation and Electrochemical Performance of Pr_(0.8)Sr_(0.2)Fe_(0.7)Ni_(0.3)O_(3-δ)-Pr_(1.2)Sr_(0.8)Ni_(0.6)Fe_(0.4)O_(4+δ) Composite Cathode

采用溶胶凝胶法制备单相Pr_(0.8)Sr_(0.2)Fe_(0.7)Ni_(0.3)O_(3-δ)(PSFN_(113))和Pr_(1.2)Sr_(0.8)Ni_(0.6)Fe_(0.6)O_(446)(PSNF_(214)),并将二者以3∶7的质量比固态混合制备PSFN;-PSNF;异质复合阴极,系统地研究异质界面的存在对样品的结构和性能的影响,并评估PSFN;-PSNF;复合材料作为中温固体氧化物燃料电池(IT-SOFC)阴极的潜力。结果表明,异质复合材料的两相间具有良好的化学稳定性和热稳定性,与Ce_(0.8)Gd_(0.2)O_(1.9)(GDC)电解质具有良好的兼容性和界面粘附性,具有长期运行稳定性。PSNF_(113)加入到PSFN_(214)中形成异质结构,可提高氧空位含量,改善PSFN;的氧离子传输。两相颗粒紧密缠绕以最大化形成异质界面,提高比表面积。800℃时,PSFN_(113)-PSNF_(214)的极化电阻值为0.053Ω·cm^(2),仅为PSFN_(113)的41%和PSNF_(214)的61%;相应单电池的最大功率密度为496.80 mW/cm^(2),高达PSFN_(113)的2.5倍和PSNF_(214)的1.6倍。60 h长期稳定性测试的电压衰减率仅为0.07%/h。因此,PSFN_(113)-PSNF_(214)异质复合阴极优异的性能和杰出的稳定性,使其可作为IT-SOFC阴极的候选材料。

Single-phase Pr_(0.8)Sr_(0.2)Fe_(0.7)Ni_(0.3)O_(3-δ)(PSFN_(113))and Pr_(1.2)Sr_(0.8)Ni_(0.6)Fe_(0.6)O_(446)(PSNF_(214))were prepared via a sol-gel method,and the PSFN_(113)-PSFN_(214)heterogeneous composite cathode was prepared via mixing the two components with the mass ratio of 3∶7.The effects of hetero-interface on the structure and properties of the samples were systematically studied,and the potential of PSFN_(113)-PSFN_(214)as an IT-SOFC(intermediate temperature solid oxide fuel cell)cathode was evaluated.The results show that the two phases of the heterogeneous composite material has good chemical and thermal stability.In addition,the heterogeneous composite material has good compatibility and interfacial adhesion with the GDC(Ce;Gd;O;)electrolyte,so it has long-term operating stability.Meanwhile,PSFN_(214)is added to PSFN_(113)to form a heterogeneous mixture,which can increase the oxygen vacancy content and improve the oxygen ion transmission of PSFN_(113).In addition,two-phase particles are tightly entangled to maximize the formation of hetero-interfaces and increase the specific surface area.At 800℃,the polarization resistance of PSFN_(113)-PSFN_(214)is 0.053Ω·cm~2,which is only 41%of PSFN_(113)’s resistance and 61%of PSFN_(214)’s resistance.The maximum power density of the corresponding single cell is 496.80 m W/cm~2,which is 2.5 times of PSFN_(113)’s densityand 1.6 times of PSFN_(214)’s density.The voltage decay rate after 60 h long-term stability test is only 0.07%/h.Therefore,the excellent performance and outstanding stability of PSFN_(113)-PSFN_(214)heterogeneous composite cathode make it a candidate material for IT-SOFC cathode.