EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

From single-crystal model catalysts to nanoparticle catalysts deposited on a substrate: Operando characterization of catalytic materials has become an important research field to unravel the complexity of catalytic reactions on the atomic level at the gas-surface interface. To bridge the pressure gap between industrial applications and surface science research , an interest in photon-in-photon-out techniques, which can be applied within a broad pressure range, has evolved.

We combine different optical techniques to simultaneously study the surface and gas properties during catalytic reactions, such as CO oxidation. Thereby, we can capture a maximum of information about the complexity of the reaction by measuring the surface and the gas phase at the same time at ambient pressures.

Polarization Modulation Infrared Reflection Absorption Spectroscopy (PM-IRRAS) probes the vibrational bonds of the adsorbed molecules, such as CO adsorption on Pd(100), while Surface Optical Reflectance (SOR) images the surface morphology over the entire sample providing us with information about surface oxide formation. Simultaneously, we measure the gas formation, e.g. CO2, above the sample using Planar Laser Induced Fluorescence (PLIF).

All techniques are incorporated in a unique compact setup that provides measurements that complement synchrotron-based measurements, and can also be combined with such techniques. We will describe the technical setup and present its capabilities by showing simultaneous data from all techniques in an operando study of CO oxidation over Pd(100).