Abstract

We report a comparative study of unsteady behavior of CO oxidation over silica-supported platinum and Pt(100). Experiments were performed in a reaction cell allowing the first direct comparison between both catalyst types under the same conditions at pressures between 10 and 100 mTorr. The reaction is examined with mass spectrometry, time-resolved FT-IR spectroscopy, and ellipsomicroscopy for surface imaging (EMSI). For the supported catalyst, our measurements concentrated on the reaction rate as a function of control parameters pressure and temperature and time-resolved FT-IR, EMSI was used to follow spatio-temporal pattern formation on the Pt(100) single crystal. The parameter space (partial pressures of the reactants, catalyst temperature, pumping speed of the reactor) for unsteady behavior of the CO oxidation is much wider for the supported catalyst. In certain parameter ranges, spatio-temporal pattern formation governs the unsteady behavior of the single crystal, while for other parameters, very regular oscillations with no pattern formation are observed. Time-resolved FTIR spectroscopy was used to follow the CO coverages under reaction conditions, which stayed below 15% of the maximum coverage

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.