Study of the surface chemistry of ethyl groups on Pt(111) by using partially deuterated ethyl iodide

Journal Article · Thu Oct 18 04:00:00 EDT 1990 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100384a065· OSTI ID:6045284

Zaera, F ^[1]

---

1. Univ. of California, Riverside (USA)

The surface chemistry of ethyl iodide was studied by using thermal programmed desorption (TPD) spectroscopy. Partially deuterated ethyl iodide molecules (CD{sub 3}CH{sub 2}I and CH{sub 3}CD{sub 2}I) were used to determine the mechanism for the reactivity of ethyl groups on the surface. Breaking of the C-I bond on Pt(111) at temperatures below 200 K results in the formation of ethyl moieities. The thermal desorption experiments suggest that those ethyl groups dehydrogenate immediately after being formed to yield ethylene. Partial deuterium labeling on the ethyl moeities was used to demonstrate that such reaction occurs by elimination of a hydrogen atom in the {beta} position (the farthest from the surface). Chemisorbed ethylene rehydrogenates at higher temperatures to form ethyl groups again, which then either hydrogenate immediately to form ethane or dehydrogenate back to ethylene (a mechanism responsible for H-D exchange). Additional experiments in which hydrogen or deuterium was coadsorbed with the ethyl iodide also help in elucidating the mechanism for the reactions involved. Finally, the authors used the kinetic information obtained with TPD to calculate the energetics of the surface steps studies here.

• OSTI ID: 6045284
• Journal Information: Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:21; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
DATA
DEUTERIUM COMPOUNDS
ELEMENTS
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
HYDROGEN COMPOUNDS
INFORMATION
IODIDES
IODINE COMPOUNDS
MEASURING METHODS
METALS
NUMERICAL DATA
PLATINUM
PLATINUM METALS
SURFACE PROPERTIES
THERMAL ANALYSIS
TRANSITION ELEMENTS