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研究了Nd2NiO4+δ (NNO)-Ce0.sGd0.2O2-δ (CGO)复合化合物在中温固体氧化物燃料电池的性能,包括NNO-CGO复合阴极的烧结温度以及复合比例.采用流延法、丝网印刷法和高温烧结法相结合制备了尺寸为50mm×50 mm的平板式NiO-YSZ阳极支撑SOFC.单电池是由NiO-YSZ阳极支撑层、NiO-YSZ阳极功能层、YSZ电解质层,CGO阻挡层,NNO-CGO复合阴极层以及La0.6Sr0.4CoO3-δ (LSC)集流层共同组成.研究结果表明,当70NNO-30CGO复合阴极烧结温度为1000℃,单电池在800℃展现出最大功率密度385 mW/cm2 (0.7 V),欧姆阻抗、极化阻抗和面积比电阻分别为0.31、0.266和0.576Ω.cm2.电化学阻抗分析结果表明,电荷转移阻抗是电池极化阻抗的主要来源.测试后电池截面的SEM观察结果显示电池各层之间均展现出良好的烧结结合.同时,与前期研究结果比较可以发现,具有相同复合阴极层的电池增加CGO阻挡层后功率密度下降,欧姆阻抗增加,但极化阻抗却降低.

Nd2NiO4+δ (NNO)-Ce0.sGd0.2O2-δ (CGO)composites were further investigated as cathodes for intermediate temperature solid oxide fuel cells (IT-SOFCs).The effects of sintering temperature and the relative proportions of NNO and CGO on the cell performances were systematically investigated.Planar NiO-YSZ anode-supported cells in commercial size of 50 mm×50 mm were fabricated by tape casting,screen printing and co-sintering methods.A single cell consisted of a NiO-YSZ anode support,a NiO-YSZ anode interlayer,a YSZ electrolyte layer,a CGO interlayer,a NNO-CGO composite cathode layer,and a La0.6Sr0.4CoO3-δ (LSC) current collector from anode to cathode.The results show that the cell with 70NNO-30CGO composite cathode sintered at 1000C exhibits the highest power density of 385 mW/cm2 at 0.7 V at 800C.The ohmic resistance,polarization resistance and area specific resistance are 0.31,0.266 and 0.576 Ω·cm2,respectively.The analysis of electrochemical impedance spectra indicates that the polarization resistance mainly comes from charge transfer resistance.SEM image of the cross-section of the cell after testing reveals that each layer has a good adhesion.Meanwhile,compared with previous research,it can be concluded that adding a CGO interlayer in the single cells leads to an increase in the ohmic resistances and a decrease in the power densities,whereas the values of the polarization resistances decrease.