Self-Assembled Monolayer Growth of Polyethlyene Oxide on Polymer Electrolyte

Indianapolis, IN

Polymer electrolyte materials used in lithium polymer batteries have the problem of degradation at the interface where the polymer contacts the electrodes (anode and cathode). One way to potentially mitigate the problem is to protect the polymer by introducing a Self-Assembled Monolayer (SAM) to the polymer surface. A SAM is a single molecular layer, grown on the surface, which binds to the polymer forming a protective barrier between the polymer and electrode surfaces that slows down degradation without affecting the polymer's performance. In this work, the growth and characterization of a SAM film on a polymer electrolyte was monitored through the use of Atomic Force Microscopy (AFM) and Infrared Spectroscopy. The growth of the SAM film on the polymer was verified by IR Spectroscopy as an increase in intensity of spectral features at 2920-2840 cm^-1 corresponding to CH₂ stretch in the SAM. AFM images showed the SAM films on the polymer were different than the original uncovered polymer film. These observations proved useful in understand the degradation process at the surface of the polymer electrolyte.