AVS 47th International Symposium
    Material Characterization Tuesday Sessions
       Session MC-TuM

Paper MC-TuM6
Pt-Metal Oxide Aerogel Catalysts: An X-ray Photoemission Investigation

Tuesday, October 3, 2000, 10:00 am, Room 207

Session: Real World Surface Analysis
Presenter: A.J. Nelson, Lawrence Livermore National Laboratory
Authors: A.J. Nelson, Lawrence Livermore National Laboratory
J.G. Reynolds, Lawrence Livermore National Laboratory
Correspondent: Click to Email
X-ray photoemission spectroscopy was used to study Pt-metal oxide aerogel catalysts that have been developed to respond to increased NO@sub x@ emissions of lean-burn engines. Lean-burn engines, critical components of low and zero emission vehicles, produce much higher levels of engine-out NO@sub x@ and current three-way catalytic converters are not sufficient to meet Clean Air Act standards. Platinum catalysts were formed by the reaction of modified Pt coordination compounds with selected transition-metal alkoxides through sol-gel techniques into aerogels. Photoemission measurements on the valence band electronic structure and Pt 4f, Si 2p, Ti 2p and O 1s core lines were used to evaluate the chemistry of the material after each processing step. Results indicate Pt-O bonding and reduced Pt disbursed in the aerogel. In addition, Si 2p, Ti 2p and O 1s binding energies indicate an oxo-bridged network structure.