Band alignment at Pt/PTFE interface: XPS experiment and first-principles calculation

Since charge injection from metal into dielectrics leads to electrical degradation and failure of various electrical and power devices, it is essential to reveal the band alignment of the metal/dielectric interface. However, the band alignment of the metal/dielectric interface remains theoretically unexplored and has not been experimentally obtained. This study reveals the band alignment at the Pt/polytetrafluoroethylene (PTFE) interface by X-ray photoelectron spectroscopy (XPS) measurements and first-principles calculations using density functional theory (DFT). Experiments reveal that the electron and hole injection barriers are 5.5 eV and 2.9 eV, respectively. The calculated results agree with the experimental results, indicating that the vacuum level shift at the interface is slight. Therefore, the band alignment at the Pt/PTFE interface is similar to that before contact.