物理化学学报 >> 2006, Vol. 22 >> Issue (09): 1043-1046.doi: 10.3866/PKU.WHXB20060901

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碘乙醇在Ni(100)表面的化学热反应

赵清;张慧敏;Francisco Zaera   

  1. 北京理工大学理学院物理系, 北京 100088; Department of Chemistry, University of California, Riverside, California 92521, USA
  • 收稿日期:2006-04-05 修回日期:2006-06-14 发布日期:2006-09-04
  • 通讯作者: 赵清 E-mail:qzhaoyuping@163.com

Chemical Thermal Decomposition of 2-iodoethanol on Ni(100)

ZHAO Qing;ZHANG Hui-Min;ZAERA Francisco   

  1. Department of Physics, College of Science, Beijing Institute of Technology, Beijing 100088, P. R. China; Department of Chemistry, University of California, Riverside, California 92521, USA
  • Received:2006-04-05 Revised:2006-06-14 Published:2006-09-04
  • Contact: ZHAO Qing E-mail:qzhaoyuping@163.com

摘要: 利用热脱附(TPD)实验和X射线光电子能谱(XPS)研究了碘乙醇在Ni(100)表面的吸附和热反应过程. 实验结果表明, 碘乙醇在100 K温度下以两种分子的形式吸附在Ni(100)的表面, 既有碘原子端的吸附也有碘原子端和羟基端同时吸附在表面. 热分解反应发生在140 K, 伴有少量的乙烯和水产生. 碘乙醇在150 K经过C—I键断裂形成−O(H)CH2CH2−和羟乙基两种中间产物. 在160 K温度下−O(H)CH2CH2−脱去氢形成−OCH2CH2−氧金属环. 中间产物经过进一步分解氧化反应分别在210和250 K产生乙醛, 一部分乙醛从表面脱出, 而其余的则分解成氢气、水和CO.

关键词: 碘乙醇, 热脱附(TPD), Ni(100)

Abstract: The temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to study the adsorption and thermal decomposition of 2-iodoethanol on clean Ni(100). The results show that 2-iodoethanol adsorbs molecularly at 100 K in two ways, either just by iodine atom or by both iodine and hydroxyl ends of the molecule. A thermal decomposition starts around 140 K with the production of small amounts of ethylene and water. The bulk of the 2-iodoethanol decomposes at about 150 K via a carbon-iodine scission to form −O(H)CH2CH2− and 2-hydroxyethyl intermediates. Around 160 K the −O(H)CH2CH2− dehydrogenates to an oxametallacycle species (−OCH2CH2−). The two intermediates further decompose to acetaldehyde, at around 210 K and above 250 K, respectively, and some of the acetaldehyde desorbs while the rest decomposes to hydrogen and carbon monoxide.

Key words: 2-iodoethanol, TPD, Ni(100)