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研究论文

吸附态和溶液相CO在Pt(110)电极上氧化过程的CV和in situ FTIRS 研究

  • 田莉 ,
  • 李君涛 ,
  • 叶进裕 ,
  • 甄春花 ,
  • 孙世刚
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  • 厦门大学固体表面物理化学国家重点实验室,化学化工学院化学系,能源研究院;

收稿日期: 2010-08-28

  修回日期: 2010-08-28

  网络出版日期: 2010-08-28

Studies of oxidation Processes of Adsorbed and Solution CO on Pt(110) Electrode by Cyclic Voltammetry and in situ FTIRS

  • TIAN Li ,
  • LI Jun-tao ,
  • YE Jin-yu ,
  • ZHEN Chun-hua ,
  • SUN Shi-gang
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  • ( State Key Laboratory of Physical Chemistry of Solid Surfaces,Department of Chemistry, College of Chemistry and Chemical Engineering,School of Energy Research,Xiamen University, Xiamen 361005,Fujian,China

Received date: 2010-08-28

  Revised date: 2010-08-28

  Online published: 2010-08-28

摘要

应用电化学原位傅里叶变换红外反射光谱(in situ FTIRS)研究了酸性介质中Pt(110)单晶电极上吸附态CO(COad)和溶液相CO(COsol)的氧化过程.循环伏安测试表明,COsol氧化的峰电位比COad氧化的正移了168mV,其峰电流密度为后者的6.7倍.电化学原位红外光谱检测到CO主要生成线型的吸附态物种(COL),均匀分布在Pt(110)表面上.当溶液中不存在CO时,COL仅在电位高于0.15V才发生氧化.而且,该谱峰在其稳定吸附的电位区间内随电位增加蓝移,Stark系数为30cm-1·V-1;在COL发生氧化的电位区间,其谱峰强度随电位增加减小、峰位红移,线性变化率为-56cm-1·V-1.溶液中饱和CO时,原位红外光谱在-0.05V即可检测到CO2的存在,显示COL起始氧化的电位提前了200mV;电位高于-0.05V,该谱峰即发生红移,对应的线性变化率为-26.5cm-1·V-1.

本文引用格式

田莉 , 李君涛 , 叶进裕 , 甄春花 , 孙世刚 . 吸附态和溶液相CO在Pt(110)电极上氧化过程的CV和in situ FTIRS 研究[J]. 电化学, 2010 , 16(3) : 285 -289 . DOI: 10.61558/2993-074X.3357

Abstract

The oxidation processes of adsorbed CO (COad) and solution phase CO (COsol) on Pt(110) electrode were investigated by cyclic voltammetry and in-situ FTIR spectroscopy. It has revealed that in comparison with COad on Pt(110) in a CO-free solution,the oxidation current peak of COsol in a CO-saturated solution is positively shifted ca. 168 mV,and the peak current density has been increased by 6. 70 times. Linear adsorbed CO (COL) is determined by in-situ FTIR spectroscopy as the main species,which is uniformly distributed on Pt (110) surface. In a CO-free solution,the onset potential of COL is measured by in-situ FTIRS ca. 0. 15 V; the COL band is blue-shifted with the increase of electrode potential in the potential range where COL is stable,yielding a Stark tuning rate 30 cm -1·V -1; when the COL is oxidized at E > 0. 15 V,the COL band is red-shifted at a rate of - 56 cm -1·V -1. In the case of CO-saturated solution,the CO2 band could be appeared in the in-situ FTIR spectrum recorded at - 0. 05 V,demonstrating that the onset potential of COL oxidation is negatively shifted ca. 200 mV in comparison with Pt( 110) in a CO-free solution; the COL band is immediately red-shifted with a rate of - 26. 5 cm -1·V -1 when the potential is above - 0. 05 V.

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