Kinetics of Surface Reactions Studied by Laser-Induced Thermal Desorption and FTMS

该建议是在一般领域的分析和表面 化学和表面化学动力学 问题研究 两位研究人员约翰·亨明格博士 和罗伯特·麦克伊弗，结合起来，利用一种新的方法， 先前开发的涉及激光诱导热解吸的 在化学反应过程中的瞬态物种， 通过傅里叶变换质谱法检测。 关键 该方法的优点是能够检测多个 物种同时 该方法将用于研究 共吸附烃分子转化动力学 含杂原子的分子作为 在充分表征的单晶中的浓度和覆盖度 表面。 特别是，使用激光诱导热的研究 解吸-傅立叶变换质谱法将 重点抓好三个项目。 第一个是研究 铂上两种共吸附物的集体现象 111！as a function函数of coverage覆盖. 第二，复杂 转化，如简单烷烃的脱氢环化， 烯烃在催化相关的单晶表面上。 第三个项目将侧重于铋的影响 后给药，以阻断特定的表面化学位点， 吸附质，从而检查这种堵塞对 Pt 111上乙烯向乙炔的转化动力学。

This proposal is in the general area of analytical and surface chemistry and in the subfield of surface chemical kinetic studies. The efforts of two investigators, Drs. John Hemminger and Robert McIver, are combined to utilize a new approach previously developed involving laser induced thermal desorption of transient species during a chemical reaction, and their detection by Fourier transform mass spectrometry. The key advantage of this method is the ability to detect multiple species simultaneously. The method will be used to study the kinetics of transformation of hydrocarbon molecules coadsorbed with heteroatom containing molecules as a function of concentration and coverage at well characterized single crystal surfaces. In particular, the studies using the laser induced thermal desorption-Fourier transform mass spectrometry method will focus on three projects. The first involves the study of collective phenomena involving two coadsorbates on platinum ı111! as a function of coverage. The second involves complex tranformations such as dehydrocyclization of simple alkanes and alkenes over catalytically relevent single crystal surfaces. The third project will focus on the effects of bismuth postdosing to block specific surface chemical sites on the adsorbate, thereby examining the influence of such blockage on transformation kinetics of ethylene to ethylidyne on Ptı111!.