X-ray Photoelectron Spectroscopy (XPS) is a mature technique used for studying the surface chemistry of solids. It involves shining X-rays onto the sample to eject electrons from the atoms in the surface and near-surface regions. Counting the emitted electrons and measuring their kinetic energy provides information about what elements are present at the material’s surface, their chemical state, and in what quantities they are found.
This Essential Knowledge Briefing aims to provide a simple introduction to XPS, detailing some of the specific implementations, discussing problems that can arise and exploring the developments that are likely to be seen with this technique in the future.