Judith L. Jenkins
Organic electronics, devices constructed from electronically active small molecules and polymers, are promising candidates for energy efficient consumer electronics (OLED lighting and OLED televisions), medical applications (pacemakers, drug delivery, smart prosthetics), and emerging energy conversion and energy storage platforms (batteries, supercapacitors). Further advances in these and other areas are limited by the need for materials that effectively conduct both electrons and ions. Conducting polymers are promising candidates for organic electronic platforms requiring mixed ionic-electronic conduction, and these polymers are flexible, inexpensive to make, and highly tunable. However, ion conduction in electrically active polymers is poorly understood, motivating the work presented here. In our lab, we use electrochemistry to make (electropolymerize) and characterize conducting polymer films. In particular, we are interested synergistically varying the polymer composition, the ionic species present during electropolymerization, and the electrodeposition parameters to tune both the electrical and ionic conductivity of the resulting polymer films. In these preliminary experiments, thiophene monomers were used to develop a method for screening electrodeposition parameters. Each monomer oxidation potential was determined with linear sweep voltammetry. Electrodeposition trials featured both cyclic voltammetry and potential-step approaches. Polymer film stability was evaluated with cyclic voltammetry. Together, these experiments represent a repeatable methodology for screening new monomers and tuning electrodeposition parameters to yield stable polymer films. Additionally, the thiophene materials generated here will be further evaluated for use in mixed electronic-ionic conduction platforms. Ultimately, these results demonstrate some of the ways EKU students are contributing to the development of highly functional organic electronics for biosensing and energy conversion platforms.