The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes

	The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes
	Wang, SZ; Jiang, Y; Zhang, YH; Yan, JW; Li, WZ
刊名	journal of the electrochemical society
	1998-06-01
卷号	145 期号:6 页码:1932-1939
英文摘要	in this study, 8 mol % yttria stabilized zirconia (ysz) + la0.8sr0.2mno3 (lsm) composite electrodes with addition of various amounts of ysz were prepared on ysz plates by a screen-printing method. the electrodes were then examined by scanning electron microscopy (sem) and studied by ac impedance, cyclic voltammetry, and potential step as well as a polarization technique. for the oxygen reduction reaction on the pure lsm electrode, the dissociative adsorption of oxygen on the lsm surface and the transfer of oxygen ions from the triple-phase boundary (tpb) to the ysz electrolyte lattice were found to be two comparable rate-determining steps. the electrochemical resistance of the former step was proportional to the -0.5 power of p(o2), with a high activation energy of similar to 2.0 ev. the electrochemical resistance of the latter step was found to be independent of p(o2), with a low activation energy of similar to 1.0 ev. with addition of ysz to the lsm electrode, the electrochemical activity was improved substantially with much lower electrochemical resistances for both steps. furthermore, the dissociative adsorption of oxygen became less rate determining on the electrode with more ysz addition. it was found that the transfer of oxygen ion was the only rate-determining step on the 40% ysz + lsm electrode. the improvement in the electrochemical performance with addition of ysz was found mainly due to the spatial enlargement of the tpb area, which increased the electrochemically active sites for the oxygen adsorption and charge-transfer reaction. the intimate sintering of ysz particles to the ysz substrate and the subsequent formation of the spatial tpb area were directly found by sem examination and further confirmed by the increasing cathodic currents from the tpb area, which were separated from the total currents using a potential-step technique.
WOS标题词	science & technology ; physical sciences ; technology
类目[WOS]	electrochemistry ; materials science, coatings & films
研究领域[WOS]	electrochemistry ; materials science
关键词[WOS]	oxide fuel-cell ; impedance spectroscopy ; cathodic polarization ; oxygen reduction ; kinetics
收录类别	SCI
语种	英语
WOS记录号	WOS:000073705200018
公开日期	2015-11-10
内容类型	期刊论文
源URL	[http://159.226.238.44/handle/321008/138124]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
作者单位	Chinese Acad Sci, Dalian Inst Chem Phys, Dalian 116023, Peoples R China
推荐引用方式 GB/T 7714	Wang, SZ,Jiang, Y,Zhang, YH,et al. The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes[J]. journal of the electrochemical society,1998,145(6):1932-1939.
APA	Wang, SZ,Jiang, Y,Zhang, YH,Yan, JW,&Li, WZ.(1998).The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes.journal of the electrochemical society,145(6),1932-1939.
MLA	Wang, SZ,et al."The role of 8 mol % yttria stabilized zirconia in the improvement of electrochemical performance of lanthanum manganite composite electrodes".journal of the electrochemical society 145.6(1998):1932-1939.