AVS 51st International Symposium
    Surface Science Tuesday Sessions
       Session SS1-TuM

Paper SS1-TuM8
High Pressure Methane Activation on Platinum Single Crystal Surfaces

Tuesday, November 16, 2004, 10:40 am, Room 210B

Session: Catalytic Reactions: The Role of Surface Steps and Structure
Presenter: A.L. Marsh, University of California, Berkeley
Authors: A.L. Marsh, University of California, Berkeley
R.M. Rioux, University of California, Berkeley
J.S. Gaughn, University of California, Berkeley
G.A. Somorjai, University of California, Berkeley and Lawrence Berkeley National Laboratory
Correspondent: Click to Email
The interest in alternative sources of energy has generated research on the conversion of hydrocarbons such as methane into hydrogen for both stationary and mobile fuel cell applications. To optimize the processes for the conversion of methane into hydrogen using platinum catalysts, reaction mechanisms must be characterized at a molecular-level. For that reason, we have characterized the high-pressure (up to 40 Torr) activation of methane on platinum single crystal surfaces using infrared-visible sum frequency generation (IR-VIS SFG) spectroscopy and Auger electron spectroscopy (AES). At low temperatures (300 K) and high pressures (1 Torr), methane is activated to form a number of different dehydrogenated intermediates on the Pt(111) surface. The extent of dehydrogenation increases with increasing temperature and pressure. In addition, the amount of carbon deposited on the surface increases with increasing temperature and pressure. Comparisons are made with molecular beam and high pressure experiments on other metal single crystal surfaces to develop a detailed mechanistic picture of the activation of methane at high pressures on platinum catalyst surfaces.