期刊
JOURNAL OF PHYSICAL CHEMISTRY B
卷 110, 期 23, 页码 11299-11309出版社
AMER CHEMICAL SOC
DOI: 10.1021/jp060099h
关键词
-
The primary aim of this work was to establish the mechanism of the oxygen reduction reaction (ORR) at (La0.8Sr0.2)(0.98)MnO3 (LSM)-based cathodes in solid oxide fuel cells. Rate equations, based on the Butler-Volmer equation and employing either Langmuir or Temkin adsorption conditions for reactant and intermediate species, were derived, yielding predicted reaction orders and transfer coefficients. Experimental data were collected using half-cell cyclic voltammetry in a variable pO(2) atmosphere (0.03 to 1 atm) at 600 to 900 degrees C, using both dense and porous LSM-based cathodes, employed to establish the impact of the accessibility of the active site on cathode activity. The rate of the ORR at dense LSM has been found to be limited by the dissociation of O-2ads(-) at low currents and by the first electron-transfer step, reducing O-2ads to O-2ads(-), at high currents. However, at porous LSM cathodes, the reaction mechanism is more difficult to deduce because the electrode morphology impacts significantly on the measured kinetic and mechanistic parameters, giving anomalous transfer coefficients of <0.5.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据