Inherent voltages of solution-cast poly(ethylene oxide) electrolyte films

CHED 471

Michael W. Kennedy, michael-kennedy@utulsa.edu, Christopher Smith, christopher-Smith@utulsa.edu, Paige L. Johnson, paige-johnson@utulsa.edu, and Dale Teeters, michael-kennedy@utulsa.edu. Department of Chemistry and Biochemistry, The University of Tulsa, 600 S. College Ave., Tulsa, OK 74104
Previous studies have shown a difference between the bulk and surface ion concentrations in films composed of poly(ethylene oxide), PEO, complexed with inorganic salts. Measurements made in our laboboratory of the through-plane potential of PEO electrolyte films cast from solution have demonstrated that they possess an inherent potential of approximately 0.2 volts. This potential can be attributed to different salt concentration gradients at the two surfaces. The cast films display a discharge behavior similar to a capacitor system and can undergo multiple charge-discharge cycles. This phenomenon will be investigated, using attenuated total reflection (ATR) surface IR spectrooscopy to study the surface concentrations of ionic species, charging and discharging studies, and a.c. impedance spectroscopy of the surface and bulk regions of the film. The ability of electrolyte films to exhibit a potential as fabricated has many potential applicatons as an easily manufactured power source for micro and nanodevices.