DISSERTATION DEFENSE
William Lowery, Chemistry
*under the direction of David Cliffel
“Development of Improved Electron Transfer Materials in Bioelectrochemical Systems”
02.26.25 | 1:30PM | 5326 Stevenson Center
*Reception following in 5502 Stevenson Center
There has been a growing interest in leveraging biological materials to solve problems related to electrochemistry in recent years. Efforts in this area have been hindered by a lack of materials that can adequately provide an interface to harness nature’s refinement. Previous studies have shown that conductive polymers are excellent candidates for providing a supportive framework to enhance the usage of such biomaterials. This dissertation focuses on improving the field of biomaterials, particularly centered on the Photosystem I (PSI) protein, a vital component necessary for photosynthesis in plants. PSI has been shown to be an excellent component to promote light-driven reactions due to its robust nature, near perfect internal quantum efficiency, and high redox potential. Through the refinement of the process of interfacing biological components to inorganic substrates, the field can further address renewable energy problems through the application of PSI. This refinement is explored in three areas: morphology, direct electronic wiring, and metal loading of the polymer. By exploring anion effects in the electropolymerization of the conductive polymer PEDOT, notable improvements were made, revealing an enhanced synergy between the two materials. In the next component, polypyrrole was grown directly out from one of the active sites of PSI, producing hybrid, photoactive nanocomposites capable of direct electron transfer. Continuing with the theme of conductive polymers, an organometallic redox polymer was also studied. While osmium-coupled poly(vinylimidazole allylamine) has been widely used in some electrochemical sensors, control of the extent of metal loading has been poorly quantified and not well optimized. This work reveals the correlation between metal loading and the effect on the resulting polymer’s electrochemical properties. Each of these areas has shown different avenues with which a system may be tuned to enhance the interface with biomaterials. Specific examples are discussed including biohybrid energy generation and microfluidic sensing. Finally, an overview of areas for improvement amongst solid-state applications is presented along with a new paradigm of characterization for electrochemical assays to significantly aid in the understanding of magnetic bead-based detection methods.
Committee members: Dr. David Cliffel, Dr. Lauren Buchanan, Dr. Janet Macdonald, Dr. Kane Jennings