【摘要】 以NiO和Ce0．8Gd0．2O1．9(CGO)为原料,通过静压成型,在1450℃高温焙烧,并于 700℃用80％He气稀释的H2还原后,制成了Ni-CGO中温固体氧化物燃料电池(SOFC)阳极,测定了阳极的孔特性,用SEM观察了阳极的微观形貌,通过XRD衍射图谱表征了阳极材料还原前后的晶相变化,用EDS分析了阳极的元素组成与分布,测试了阳极的电导率和燃料电池性能．研究结果表明,所制备的Ni-CGO阳极孔径主要在1-2μm,孔隙率随NiO含量的增加而增大,最大可达到30％．通过SEM观察可知金属相与CGO陶瓷相融合良好,阳极与电解质结合紧密,用20％的H2气体700℃可将NiO彻底还原成金属Ni,但是CGO晶相没有变化,还原后的阳极电导率随NiO量减少而降低,NiO质量比为40％时是电导率的阈值; 用Ni-CGO为阳极,CGO为电解质,LSCF为阴极制备的中温SOFC功率密度650℃可达 0．14W／cm2．更多还原

【Abstract】 Ni-Ce0.8Gd0.2O1.9 (CGO) cermet anodes of intermediate temperature solid oxide fuel cells (IT-SOFCs) were prepared by the iso-static pressing method, which were sintered at 1450℃ and successively reduced at 700℃ with H2 diluted by 80% He. The resulting anodes were characterized by the pore structure measurements, SEM, XRD and EDS as well. The conductivity and the electrical performance in corresponding cells were also measured. The prepared Ni-CGO cermet anodes mainly possess the pores of 1-2μm in diameter and the porosity of up to 30% that increases with the content of NiO. It can be observed by the SEM measurements that the metal phase is well amalgamated with the ceramic phase and that the anode combines with the electrolyte tightly. NiO in the anodes can be reduced to Ni completely by the mixture of 20%H2-80%He at 700℃ without the phase transformation of CGO. The conductivity of the reduced anode increases as the NiO content increases. The threshold value of the NiO content is 40% in weight, over which the remarkable increase in conductivity is not available. The fuel cells composed of Ni-CGO as the anode, CGO as the electrolyte and La0.6Sr0.4Co0.2Fe0.8O3-α(LSCF) as the cathode provide with the power density of up to 0.14W/cm2 at 650℃.更多还原