Development of combined operando diagnostics : Applications in heterogeneous catalysis and electrochemistry
Author
Summary, in English
With the aim to bridge the pressure gap between traditional surface science and industrial applications, heterogeneous catalytic reactions on model catalysts are increasingly studied at near-ambient pressures. Under those conditions, the gas phase has been shown to play an important role during the interaction at the gas-surface interface making it complex to study. This complexity can be captured by simultaneously measuring different properties of the gas-surface interaction operando while the reaction takes place. Since each diagnostic tool offers unique information, combining them provides a fuller understanding of the reaction.
This thesis presents a combination of three laser- and optical-based operando techniques that have been combined in a versatile in-house setup. We have shown that planar laser-induced fluorescence (PLIF), two dimensional-surface optical reflectance (2D-SOR) and polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS) can be combined, either simultaneously or in various configurations, to study CO oxidation on different Pd-based model catalysts. Thereby, chemical and structural information about the surface and chemical information about the gas phase can be obtained in space and temporally resolved.
Moreover, some of the in-house optical techniques are combined with synchrotron-based techniques to extract more chemical and structural information than can be obtained from one measurement. This is demonstrated with simultaneous measurements combining PM-IRRAS and ambient pressure X-ray photoelectron spectroscopy (AP-XPS) for different gas-phase catalysis reactions and 2D-SOR with High Energy Surface X-ray Diffraction (HESXRD) for electrochemical studies.
This thesis presents a combination of three laser- and optical-based operando techniques that have been combined in a versatile in-house setup. We have shown that planar laser-induced fluorescence (PLIF), two dimensional-surface optical reflectance (2D-SOR) and polarization modulation-infrared reflection absorption spectroscopy (PM-IRRAS) can be combined, either simultaneously or in various configurations, to study CO oxidation on different Pd-based model catalysts. Thereby, chemical and structural information about the surface and chemical information about the gas phase can be obtained in space and temporally resolved.
Moreover, some of the in-house optical techniques are combined with synchrotron-based techniques to extract more chemical and structural information than can be obtained from one measurement. This is demonstrated with simultaneous measurements combining PM-IRRAS and ambient pressure X-ray photoelectron spectroscopy (AP-XPS) for different gas-phase catalysis reactions and 2D-SOR with High Energy Surface X-ray Diffraction (HESXRD) for electrochemical studies.
Department/s
Publishing year
2024-03-22
Language
English
Full text
- Available as PDF - 40 MB
- Download statistics
Document type
Dissertation
Publisher
Department of Physics, Lund University
Topic
- Atom and Molecular Physics and Optics
Status
Published
ISBN/ISSN/Other
- ISBN: 978-91-8039-999-9
- ISBN: 978-91-8039-998-2
Defence date
26 April 2024
Defence time
09:15
Defence place
Lecture Hall Rydbergsalen, Department of Physics, Professorsgatan 1, Faculty of Engineering LTH, Lund University, Lund. The dissertation will be live streamed, but part of the premises is to be excluded from the live stream.
Opponent
- Gareth Parkinson (Prof.)