AVS 52nd International Symposium
    Surface Science Monday Sessions
       Session SS-MoP

Paper SS-MoP3
Alkylidene Functionalization of Molybdenum Carbide Surfaces: Thermal Stability and Chemical Reactivity

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Surface Science Poster Session
Presenter: I. Temprano, Université Laval, Canada
Authors: H. Oudghiri-Hassani, Université Laval, Canada
M. Siaj, Université Laval, Canada
I. Temprano, Université Laval, Canada
C. Maltais, Université Laval, Canada
P.H. McBreen, Université Laval, Canada
Correspondent: Click to Email
Metal carbides possess a blend of metallic and ceramic properties and are amenable to unique surface modification procedures. In particular, molybdenum carbide surfaces may be functionalized using alkylidene groups. Such groups involve a double bond between the organic component and a single molybdenum atom at the surface, as distinct from bridge-bonded structures. We have previously shown that surface alkylidenes on molybdenum carbide display anomalously high thermal stability. The origins of this thermal stability will be discussed on the basis of extensive synchrotron photoemission, RAIRS and isotope substitution desorption data. The combined data reveal a key role for excess surface carbon in stabilizing the alkylidene groups to temperatures as high as 900 K. Furthermore, it will be shown that the metathesis activity of the surface alkylidene initiating sites may be used to perform add-on functionalization using a variety of olefins and substituted olefins.