Optical Imaging Techniques in Surface Science
- Sebastian Pfaff (Lund University, Sweden)
- Tuesday 31 March 2020
- Hotel NH Noordwijk Conference Centre Leeuwenhorst
Sebastian Pfaffa, Alfred Larssona, Lisa Rämischa, Sabrina Gerickea, Edvin Lundgrena and Johan Zetterberga
aLund University, Sölvegatan 14, Lund, Sweden
The switch to more in-situ studies of surface-gas interactions at high pressures has sparked an interest in further development of surface sensitive techniques that operate at higher pressures. Most of these techniques, however, such as ambient pressure XPS (AP-XPS), High-Pressure Surface Tunneling Microscopy (HP-STM) or High Energy Surface X-Ray Diffraction (HESXRD) require complex experimental setups.
In this work, show a simple setup for Surface Optical Reflectance (SOR) which can be used as an indicator of surface roughness and level of oxidation in operando conditions. By using a microscope, one can even image the oxidation of separate surface domains in-situ, given that the sample is polycrystalline, which can be useful for simultaneous characterisation of multiple rotational domains. The results can then be compared to those obtained though simultaneous measurements with HESXRD, which in a way provides a “calibration” to map reflectivity changes to oxidation and roughness.
We would like to acknowledge funding from the Swedish Research Council (Vetenskapsrådet), the Swedish Foundation for Strategic Research (Stiftelsen för strategisk forskning) as well as the Knut and Alice Wallenberg Foundation.
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