...
首页> 外文期刊>Journal of solid state electrochemistry >Apparent transfer coefficient for ORR at polycrystalline platinum under convection conditions: A potential modulation study
【24h】

Apparent transfer coefficient for ORR at polycrystalline platinum under convection conditions: A potential modulation study

机译:对流条件下多晶铂上ORR的表观传递系数:潜在的调制研究

获取原文
获取原文并翻译 | 示例
           

摘要

The oxygen reduction reaction has been studied in the thin-layer flow through cell at polycrystalline platinum in 0.5 M H_2SO_4 at different flow rates. The apparent transfer coefficient (α′) and the corresponding Tafel slope have been calculated using the previously introduced ac voltammetry method [1, 2]. In addition to the correction of the high electrolyte resistance in the thin-layer cell, the contribution from other adsorption processes presented by the adsorption resistance has been also subtracted. The effect of increasing convection on the obtained α′ and Tafel slopes has been examined and it was found that the apparent cathodic transfer coefficient is 0.5 (corresponding to a Tafel slope of -120 mV dec ~(-1)) in all cases independent of the flow rate or frequency, suggesting that the first electron transfer to oxygen is the rate-determining step. The difference between Tafel slopes obtained here, i.e., by ac voltammetry method, and that obtained from usual Tafel slopes is due to the potential dependence of oxygen adsorbates, which in the method used here is - at least in part - separated from the potential dependence of the rate constant.
机译:已经研究了在0.5 M H_2SO_4中以不同流速在多晶铂中流过电池的薄层流中的氧还原反应。表观传递系数(α')和相应的塔菲尔斜率已使用先前引入的交流伏安法[1、2]进行了计算。除了校正薄层电池中的高电解质电阻外,还减去了由其他吸附过程引起的吸附电阻的贡献。研究了对流对获得的α'和Tafel斜率的影响,发现在所有情况下,表观阴极转移系数均为0.5(对应于-120 mV dec〜(-1)的Tafel斜率)。流速或频率,表明电子向氧气的首次转移是速率确定的步骤。此处通过交流伏安法获得的Tafel斜率与通常的Tafel斜率之间的差是由于氧吸附物的电势依赖性引起的,在此处使用的方法中,这至少部分与电势依赖性分开了速率常数。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号