中温固体氧化物燃料电池阴极材料SrCO1-xGaxO3-δ的制备及性能研究

摘要

Cathode materials of SrCo1-xGaxO3-δ(x=0,0.1,0.2,0.3,0.4)for intermediate temperature solid oxide fuel cells(IT-SOFC)were synthesized by an Ethylene Diamine Tetraacetie Acid(EDTA)-citrate complexing method.The obtained samples were characterized by X-ray diffraction,thermal expansion measurement,X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy,and the effects of Ga-doping on performance and properties of materials were evaluated.The results show that all the samples have brownmillerite structure.The thermal expansion coefficient(TEC),electrical conductivity and the amount of adsorbed oxygen on the surface of the cathode materials gradually decrease with Ga content increasing.Among the as-abtained samples,SrCo0.8Ga0.2O3-δ shows the lowest area specific resistance(ASR)of 0.73 Ω·cm2 at 600℃,the single-cell with it as cathode demonstrates a maximum power density of 0.484 W/cm2 at 650℃.%采用EDTA-柠檬酸联合络合法制备了SrCo1-xGaxO3-δ(x=0、0.1、0.2、0.3、0.4)系列阴极材料.通过X射线衍射、热膨胀测试、X射线光电子能谱和电化学阻抗谱等方法对试样进行分析,研究了Ga掺杂量对材料性能的影响.结果表明试样均为钙铁矿结构,随着Ga含量的增加,阴极粉体材料热膨胀系数、电导率和阴极材料表面的吸附氧逐渐减小.其中,SrCo0.8Ga0.2O3-δ的面电阻最小,600℃时为0.73 Ω·cm2,以其为阴极的单电池在650℃的工作温度下的最大输出功率达0.484 W/cm2.