Scientific progress is strongly linked to developments in methods of characterization - to control something, we need to understand it, and to understand something, we need to be able to probe it. For example, it would be hard to imagine modern biology without optical microscopy, nanotechnology without electron microscopy, synthetic organic chemistry without nuclear magnetic resonance (NMR) spectrometry, or astronomy without telescopes. In a similar manner, surface science is reliant on techniques that allow us to probe the chemical compositions of surfaces. In order to understand phenomena like corrosion and degradation, processes like heterogeneous catalysis, or the operation of various functional surfaces, e.g. antimicrobial surface coatings or gas sensors, we need to be able to determine the structures of surfaces at the atomic level. In other words, we need to be able to study the chemical compositions of surfaces.
X-ray Photoelectron Spectroscopy (XPS) is one of the most commonly used analytical techniques in experimental surface science. In XPS, the energy that is required to remove a core electron from a particular atom is measured. Since that energy depends on the chemical environment of the atom, an XPS spectrum contains valuable information about surface chemistry. However, the interpretation of XPS spectra is challenging. Often, a detailed spectrum of a complex surface can be acquired, but it can be of little value if the origin of the detected spectral features is not understood. Such problems in the analysis of XPS spectra are widespread, and commonly discussed in the scientific literature.
The aim of this project is to develop novel computational methods for guiding the analysis of XPS spectra and to test them in real-world applications, by bringing together theoreticians with research groups involved in experimental surface science. Our ultimate goal is to advance surface science by making XPS a better and more reliable tool for determining the chemical environments of surface atoms.