X-Ray Photoelectron Spectroscopy (XPS): Principles and Application for the Analysis of Photoactive Materials

X-ray photoelectron spectroscopy (XPS) plays a crucial role in the surface analysis of different organic and inorganic materials. The information that could be obtained through XPS analysis (chemical state, coordination, particle size) is very important from the material science point of view. However, the exact interpretation of the XPS results often poses problems because of the complexity of the XPS analysis and existence of various phenomena that have to be taken into account. Thus the aim of this work is to provide a general introduction on fundamental principles of XPS analysis and to help researchers in developing a good practice in XPS results interpretation especially for complex XPS spectra. The overview of most important aspects and theoretical models is presented. Examples of XPS application for analysis of photoactive materials are discussed.