In Situ Spectroscopic Investigation of Low-Temperature Oxidation of Methane over Alumina-Supported Platinum during Periodic Operation
Journal article, 2011

Methane oxidation over Pt/Al2O3 at transient inlet-gas conditions was studied in situ using synchronous energy dispersive X-ray absorption spectroscopy, Fourier transform infrared spectroscopy, and mass spectrometry. The employed combination of experimental techniques allows for simultaneous analysis of the electronic state of platinum, surface coverage of reaction intermediates/products, and catalytic activity/selectivity, respectively. By cycling of the feed gas composition between net-oxidizing and net-reducing conditions, the activity for methane oxidation can be increased as compared to continuous net-oxidizing conditions. Using the white-line area of time-resolved X-ray absorption near-edge structure spectra, a quantitative estimation of the surface O/Pt ratio indicates the formation of an inhomogeneous surface oxide on the platinum crystallites during reaction. The obtained temporary high activity can be explained through Langmuir-Hinshelwood kinetics and may result either from the formation of a partially oxidized platinum surface that is more effective for methane dissociation or, more likely, from a period with more reactive chemisorbed oxygen prior to oxide formation.

Author

Elin Becker

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Per-Anders Carlsson

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Lisa Kylhammar

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Mark A Newton

European Synchrotron Radiation Facility (ESRF)

Magnus Skoglundh

Competence Centre for Catalysis (KCK)

Chalmers, Chemical and Biological Engineering, Applied Surface Chemistry

Journal of Physical Chemistry C

1932-7447 (ISSN) 1932-7455 (eISSN)

Vol. 115 4 944-951

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Transport

Energy

Materials Science

Subject Categories

Physical Chemistry

Chemical Process Engineering

DOI

10.1021/jp103609n

More information

Created

10/7/2017