X‐Ray Photoelectron Spectroscopy Analysis of Indium and Indium‐Containing Compounds

ABSTRACT X‐ray photoelectron spectroscopy (XPS) is widely employed across various research fields due to its surface and chemical sensitivity. However, accurate interpretation poses a challenge due to the lack of comprehensive reference data in the literature, leading to misinterpretation, especially among novice users. Analyzing the chemical state of indium and indium‐containing compounds is particularly challenging due to subtle shifts in the binding energies of the commonly used 3d core line. This paper presents and discusses a collection of reference data, including the In 3d, In 3p, In 4d, In MNN, and relevant counter ion signals. Additionally, it explores other useful information such as the modified Auger parameter and Wagner (or chemical state) plots. The utility of X‐ray–induced Auger electrons is demonstrated in the speciation of mixed systems.