Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)-Ag复合阴极材料的性能研究

Study on Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)-Ag Composite Cathode Materials

为发展中温固体氧化物燃料电池(IT-SOFC)的阴极材料,用柠檬酸络合法合成了Ba0.5Sr0.5Co0.8Fe0.2O3-δ(BSCF)粉体,并在BSCF中加入一定量的金属Ag作为SOFC的阴极材料.高温电阻测试表明复合阴极材料(BSCF-Ag)比纯BSCF材料具有较高的电导率.同时用交流阻抗法研究了BSCF-Ag复合阴极材料的性能,实验结果表明BSCF-Ag复合阴极材料的极化电阻明显小于纯BSCF,在750℃BSCF的极化电阻为0.41Ω.cm2,而BSCF-Ag的电阻仅为0.12Ω.cm2,约为BSCF的1/4.这标志着参杂Ag的BSCF阴极材料的性能明显优于纯BSCF材料.

In order to develop a cathode for IT-SOFC,Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） powders were prepared by an EDTA-Pechini method,and with some Ag as the cathode materials of SOFC.Ba0.5Sr0.5Co0.8 Fe0.2O3-δ-Ag were studied for applications in IT-SOFCs.The resistance measurements showed that the addition of Ag into BSCF improved electrical conductivity of pure BSCF,and the improved conductivity resulted in attractive cathode performance.The composite materials exhibited higher conductivity than that of pure BSCF.In addition,electrochemical impedance spectra exhibited better performance of BSCF-Ag composite cathodes than pure BSCF.e.g.,the polarization resistance value of BSCF-Ag was only 0.12Ω cm2 at 750℃,about one fourth of that BSCF at 750℃.As a summary,compared to a pure BSCF cathode,it was found that adding Ag in the cathode enhanced the BSCF performance significantly.