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Download or read book Understanding the Structure-Function Relationship of Semiconducting Polymers Through Chemical and Electrochemical Doping written by Charlene Zarah Salamat and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conjugated polymers are a versatile class of materials useable in a variety of organic electronic applications, but their utilization is limited by their intrinsically low conductivity. However, doping of semiconducting polymers via oxidation of their backbone can add mobile charge carriers and increase their electrical conductivity. This can be accomplished via electrochemical doping, where an applied potential oxidizes the polymer, or via chemical doping, where a molecular oxidizer is introduced to the polymer.Electrochemical doping of semiconducting polymers is of interest because of this class of material's ability to be utilized in electrochemical cells, such as lithium-ion batteries (LIBs). This is explored in the first part of this dissertation (Chapters 2 through 7), where we investigate the application of semiconducting polymers as LIB binders. Binders are typically designed to be chemically and mechanically durable during cycling. Utilizing conjugated polymers as binders increases the electrical conductivity of the electrode, leading to reduced resistive losses and faster charging. We show that dihexyl-substituted poly(3-4-propylenedioxy-thiophene) (PPrODOT-Hx2) can serve as a binder at relevant electrochemical potentials. Additionally, we show that by either creating co-polymers with oligoether side-chains or by adding conjugation break-spacer units, we can tune ionic conductivity, heat generation, swelling, and the mechanical properties of the semiconducting polymers. While electrochemical doping has the advantage of allowing the selection of an exact potential (i.e., doping level), chemical doping is advantageous because it is fairly simple to accomplish. In the second half of this dissertation (Chapters 8 through 12), we study a variety of semiconducting polymers and dopants to understand what results in the highest conductivity in chemically doped semiconducting films. We explore the energetics and the role of crystallinity, dielectric constant, and Coulomb binding in chemical doping. Throughout this dissertation, we utilize grazing incidence wide-angle X-ray scattering (GIWAXS) to see how the structure of these polymers change upon doping, and how these structural changes map onto changes in both electronic and ionic conductivity, and optical properties.