物理化学学报 >> 2009, Vol. 25 >> Issue (05): 999-1003.doi: 10.3866/PKU.WHXB20090415

研究论文 上一篇    下一篇

阴离子特性吸附和Pt(111)电极表面结构对乙二醇解离吸附动力学的影响

樊友军 甄春花 陈声培 孙世刚   

  1. 广西师范大学化学化工学院, 广西 桂林 541004; 固体表面物理化学国家重点实验室, 厦门大学化学化工学院化学系, 福建 厦门 361005
  • 收稿日期:2008-11-17 修回日期:2008-12-31 发布日期:2009-05-04
  • 通讯作者: 樊友军 孙世刚 E-mail:youjunfan@mailbox.gxnu.edu.cn; sgsun@xmu.edu.cn

Effect of Specific Adsorption of Anions and Surface Structure of Pt(111) Electrode on Kinetics of Dissociative Adsorption of Ethylene Glycol

FAN You-Jun, ZHEN Chun-Hua, CHEN Sheng-Pei, SUN Shi-Gang   

  1. College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, Guangxi Province, P. R. China; State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China
  • Received:2008-11-17 Revised:2008-12-31 Published:2009-05-04
  • Contact: FAN You-Jun, SUN Shi-Gang E-mail:youjunfan@mailbox.gxnu.edu.cn; sgsun@xmu.edu.cn

摘要:

运用电化学循环伏安和程序电位阶跃方法研究了阴离子特性吸附和Pt(111)电极表面结构对乙二醇解离吸附反应动力学的影响. 结果表明, 阴离子特性吸附显著影响乙二醇的解离吸附, 在高氯酸介质中(无特性吸附)测得乙二醇解离吸附反应的初始速率vi以及解离吸附物种(DA)的饱和覆盖度均明显大于硫酸溶液(发生SO2-4/HSO-4特性吸附)中的相应值; 其平均速率v随电极电位的变化呈类似火山型分布, 最大值位于0.22 V(vs SCE)附近. 还发现通过不同处理获得的Pt(111)电极的不同表面结构对这一表面过程也具有显著的影响.

关键词: 乙二醇, 解离吸附, Pt(111)电极, 特性吸附, 表面结构, 表面反应动力学

Abstract:

The effect of specific adsorption of anions and the surface structure of a Pt(111) electrode on the kinetics of dissociative adsorption of ethylene glycol (EG) was studied using cyclic voltammetry and a programmed potential step technique. Quantitative results demonstrated that the specific adsorption of anions remarkably influenced the dissociative adsorption of EG. Both the initial reaction rate (vi) of the EG dissociative adsorption and the saturated coverage of dissociative adsorbates, measured in perchloric acid media (without specific adsorption), are significantly larger than the corresponding values acquired in sulfuric acid media (with specific adsorption of SO2-40/HSO-4). We illustrate that the variation of the average reaction rate v of EGdissociative adsorption on Pt(111) in perchloric acid media with an electrode potential yields a volcano-like distribution with a maximumvalue near 0.22 V (vs SCE). Furthermore, different surface structures of the Pt(111) electrode that were obtained by different treatments also significantly affect this surface process.

Key words: Ethylene glycol, Dissociative adsorption, Pt(111) electrode, Specific adsorption, Surface structure, Surface reaction kinetics

MSC2000: 

  • O646