首页> 外文期刊>Electrocatalysis >Adsorption of Acetonitrile on Platinum and its Effects on Oxygen Reduction Reaction in Acidic Aqueous Solutions-Combined Theoretical and Experimental Study
【24h】

Adsorption of Acetonitrile on Platinum and its Effects on Oxygen Reduction Reaction in Acidic Aqueous Solutions-Combined Theoretical and Experimental Study

机译:酸性水溶液中乙腈对铂的吸附及其对氧还原反应的影响-理论与实验研究相结合

获取原文
获取原文并翻译 | 示例
           

摘要

Combined theoretical and experimental study of acetonitrile (AcN) adsorption on platinum was performed and its effects on the kinetics of oxygen reduction reaction in HClO4 and H2SO4 solutions were examined. Using periodic density functional theory calculations, it was shown that AcN molecule can interact with Pt surface either through the unsaturated pi electron system or via lone electron pair of nitrogen atom. In both cases, adsorption energy decreases upon increasing coverage, while the modification of electronic structure of Pt surface is localized to the adsorption site. By combining the results of the DFT calculations with the results of blank cyclic voltammetry and rotating disk electrode voltammetry in O-2-saturated solutions, it was concluded that the effects of AcN on Pt surface chemistry and ORR kinetics are primarily steric in nature. Resulting measured ORR activities of polycrystalline platinum in the presence of AcN are due to the combination of (i) suppression of (bi)sulfate adsorption (in H2SO4 solution), (ii) suppression of surface oxidation (in both H2SO4 an HClO4 solution), and (iii) site blockage by adsorbed AcN (or products of its electrochemical transformations).
机译:结合理论和实验研究了乙腈(AcN)在铂上的吸附,并考察了其对HClO4和H2SO4溶液中氧还原反应动力学的影响。使用周期性密度泛函理论计算,结果表明AcN分子可以通过不饱和pi电子系统或通过氮原子的孤电子对与Pt表面相互作用。在这两种情况下,吸附能都随着覆盖率的增加而降低,而Pt表面电子结构的改变则局限于吸附位点。通过将DFT计算结果与O-2饱和溶液中的空白循环伏安法和旋转圆盘电极伏安法的结果相结合,得出结论,AcN对Pt表面化学和ORR动力学的影响本质上主要是空间位阻。在AcN存在下测得的多晶铂的ORR活性归因于(i)抑制(双)硫酸盐吸附(在H2SO4溶液中),(ii)抑制表面氧化(在H2SO4和HClO4溶液中), (iii)吸附的AcN(或其电化学转化产物)阻止位点。

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