Electrolyte Dependence on the Electrochemical and Optoelectronic Activity of a Conjugated Polymer in Organic Solvents

<p>Organic electronic devices rely on the redox and charge transport properties of conjugated polymers. Many high-performance electroactive polymers are hydrophobic and require processing in organic solvents. As such, these materials are characterized in nonaqueous electrolyte systems to evaluate fundamental electrochemical properties such as onsets of oxidation, current densities, and doping kinetics. Supporting electrolytes and solvents are critical parameters in electrochemical characterization and through their modulation, can yield changes in these properties. Currently, research has been largely restricted to the investigation of ionic and solvent dependences in aqueous electrolyte-based systems. It is thus important to study how these fundamental properties are affected by the use of organic electrolytes dissolved in organic solvents. The techniques implemented to study this consisted of cyclic voltammetry (CV), spectroelectrochemistry, and scan rate dependence (SRD) experiments. A regiosymmetric propylenedioxythiophene-based polymer was used to prepare solid-state films to measure electrochemical responses based on systematically varying the electrolyte identity by cationic and anionic dependence, dissolved in acetonitrile (ACN) or propylene carbonate (PC). The influence of size and extent of solvation of electrolytes impacted redox responses. Generally, increased onsets of oxidation were measured as the size of the cation and anion increased. The increased polarity of PC led to larger concentrations of free ions in solution; however the increased viscosity resulted in diffusion-limitation kinetic responses above ~200 mV/s as measured by SRD experiments. Redox responses in ACN showed no such kinetic limitations up to 1000 mV/s. These results collectively demonstrate how fundamental redox responses of conjugated polymers can be modified by organic electrolytes systems.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Masters Thesis

Year dc:date.available

2026

Author dc:creator

• Skiouris, Perry

Contributors dc:contributor

• Dr. Graham Collier
• Dr. Derek Patton
• Dr. Xiaodan Gu

• Organic electronics
• Electrochromics
• Cyclic voltammetry
• Spectroelectrochemistry
• Polymer and Organic Materials
• Polymer Chemistry
• Semiconductor and Optical Materials

Repository record dc:identifier

https://aquila.usm.edu/masters_theses/1182

OAI identifier oai:identifier

oai:aquila.usm.edu:masters_theses-2276