A Perspective on Photoelectron Spectroscopy for Materials Analysis

Photoelectron spectroscopy (PES) encompasses a range of techniques with unique roles in the analysis of materials. PES is a probe of chemical composition and environment with extreme surface sensitivity. Photoelectron spectra can be interpreted with simple ideas of atomic structure and the photoelectric effect. These ideas can explain a lot of the observed features of a photoelectron spectrum and the surface sensitivity of the technique. However, this simple picture fails to account for many of the more complex phenomena observed, especially in inorganic materials. Care must be taken in analysis of complex spectra, and materials analysis by XPS requires understanding of the atomic processes that occur during photoemission, as well as knowledge from the fields of surface science and materials chemistry.