Electron spectroscopy investigations of potassium and potassium-intercalated graphite with battery background
Steffen Oswald, Mikhail V. Gorbunov, Daria Mikhailova
Abstract
The potassium-based battery is a candidate for application in large-scale energy storage systems. However, the high reactivity of potassium causes big challenges and aggravates a detailed analysis of chemical processes in such batteries. For the investigation of the processes at the electrodes a surface characterization is necessary. Here, the focus is put on the use of X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), since with these methods in principle both, chemical and local analysis are possible. Using two model material systems K-metal and K-intercalated graphite, the capabilities and limitations of these methods are demonstrated. The challenges of the sample preparation, the spectra interpretation and the influence of electron- and ion-beam damage are discussed.