摘要
考察了Ni-钐掺杂的氧化铈(Ni-SDC)复合阳极与La_(0.9)Sr_(0.1)Ga_(0.8)Mg_(0.2)O_3(LSGM)电解质中间加入的SDC中间层对阳极及整个电池性能的影响.结果表明,SDC中间层的加入显著减小了阳极极化过电位,但同时引入了欧姆降,降低了电池的功率输出密度.氢在Ni-SDC电极的氧化主要由两个过程控制,分别对应于交流阻抗谱的两个阻抗半圆,高频环随着SDC中间层的加入显著减小,可能对应于H_2在Ni-SDC/SDC/H_2三相界的电化学氧化或氧从LSGM向SDC的传输,低频环与SDC中间层无关,可能对应于氢在电极表面的解离吸附及吸附物种的扩散过程.使用Ni-SDC/SDC夹层阳极可以明显地提高电池的稳定性.
An interlayer of samaria doped ceria(SDC) was prepared between Ni-SDC composite electrode and LSGM(La0.9Sr0.1Ga0.8Mg0.2O3) electrolyte using screen-printing method to improve the performance of Ni anodes. The effect of this interlayer on the performance of anode as well as the cell was studied using various electrochemical techniques. The results show that addition of the SDC interlayer reduced the anodic over-potential significantly, however, the ohmic resistance of the cell with an SDC interlayer increased, which leaded to a decrease of the power output. The electrochemical oxidation of H-2 on Ni-SDC anodes was controlled by two processes, which corresponded to two arcs in the impedance spectra. The high frequency arc decreased with the addition of SDC interlayer, and could correspond to the electrochemical reaction at three-phase-boundary(TPB) or the transfer of oxygen ions from LSGM to SDC. The low frequency arc showed no dependency on the addition of SDC, and could be related to the adsorption and diffusion of H-2 at the surface of electrode. The cells with an SDC interlayer showed much better stability compared with the cell using single layer anode, and the performance of the cell with Ni-SDC/SDC(1573 K) anode was higher than the cell with a single layer Ni-SDC anode after long time running.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2003年第9期849-853,共5页
Acta Physico-Chimica Sinica
基金
日本教育部"Grant in Aid for the Development of Innovative Technology
No.12307"基金~~
