Download or read book Structure function Relationships in Semiconducting Polymers written by Luke Balhorn and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving knowledge of structure-function relationships in semiconducting polymers will help design new materials that unlock new applications. This work harnesses recent advances in transmission electron microscopy of soft materials to study length scales of microstructure in these materials that have previously been difficult to probe. Further, it combines electron microscopy with structural and charge transport simulations to study the effects of mesoscale defects on charge transport in highly ordered semicrystalline polymers. Spatially resolved nanodiffraction (4D-STEM) is used to create maps of chain direction and local order in conjugated polymers. Simulations are then built upon this experimental map, first by generating molecular geometries consistent with diffraction data, then by tracking the paths of test charges across the region. A case study in this combined method is conducted using the polymer PBTTT. Short-range charge transport is shown to be more chaotic than is often pictured, with the drift velocity accounting for a small portion of overall charge motion. Local transport is sensitive to the alignment and geometry of polymer chains. At longer length scales, the curves of this PBTTT microstructure funnel charges to specific regions, creating inhomogeneous charge distributions. While alignment generally improves mobility, these funneling effects limit the overall efficiency of charge transport. The structure is modified \textit{in silico} to explore possible design rules, showing chain stiffness and alignment to be beneficial while local homogeneity has no positive effect. These observations provide direct guidance for improving mesoscale structure for future materials.
Download or read book Structure Function Relationships in Semiconducting Polymers for Organic Photovoltaics written by David Fredric Joel Kavulak and published by . This book was released on 2010 with total page 242 pages. Available in PDF, EPUB and Kindle. Book excerpt: The major body of this work investigates how the chemical structure of conjugated polymers relates to the fundamental operating mechanism of organic photovoltaic devices. New conjugated polymers were characterized and their optical and electronic properties tested and correlated with their power conversion efficiencies as the active layer in polymer solar cells. From these experiments general structure/function relationships are drawn with an eye toward developing universal guidelines for conjugated polymer design and synthesis. Starting with light absorption, three major steps in the photovoltaic mechanism are examined. First, photogeneration of excited states and the migration of these states through the active layer are correlated to the polymeric backbone chemistry and the resulting device performance. Next, separation of these excited states at an interface between electron donors and electron acceptors is examined as a function of donor-acceptor distance and active layer dielectric constant. These two variables were tuned by chemical modification of polythiophene side groups. Third, charge carrier conduction is related to both polymer electronic states and to solid-state packing morphology. Design principles for effective conduction of both holes and electrons are outlined and the ambipolar nature of conjugated organic materials is discussed. In the final chapters, the solid-state polymer morphology in a solution processed thin film is examined. The impact that this morphology has on all steps in the photovoltaic mechanism is highlighted. How chemical modification of the polymer can influence this packing structure is examined as well as how new fabrication procedures can be used to pre-form nanostructured materials in solution before thin film deposition.
Download or read book Understanding Structure Function Relationships in Semiconducting Polymer Morphology written by Katharine Adele Winchell and published by . This book was released on 2020 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconducting polymers are a promising class of materials for many organic electronic applications because of their structural tunability, low cost, and solution processability, which allows for easy scale-up. However, semiconducting polymers have intrinsically poor conductivity which limits their performance in all device applications. Polymer conductivity can be improved either by adding mobile carriers to the system or by manipulating the system to make the polymer chains more ordered on a local and global scale. This thesis studies both of these methods with a goal of improving polymer conductivity, while simultaneously seeking to understand how changes in morphology affect both local and global polymer properties. We used a variety of X-ray and neutron scattering techniques to characterize polymer structure, coupled with electronic and spectroscopic experiments to gain a full picture of polymer structure-function relationship. The first half of this thesis studies the structural changes that result from introducing a molecular dopant and additional charge carriers into the polymer network, and how those change control the resulting electronic and optical properties. We start by studying a novel class of large, redox-tunable dodecaborane-based dopants. From these studies we are able to determine how redox potential controls both dopant infiltration into polymer films and the resulting film structure, providing insight into the relationship between structure and conductivity for doped conjugated polymer systems. Using traditional small-molecule dopants, we also studied various doping methods to assess scalability and application to thick polymer films. The second half of this thesis presents studies on various methods to manipulate the local morphology of polymer chains to increase their overall order. We first used an aqueous amphiphilic self-assembly system where we developed structural design rules for order assembly and demonstrate that they can be used to create polymer system that show straightened chains when self-assembled. Next, we explored a set of block-copolymers whose co-crystallization properties could be changed using the polymer molecular weight; here we show that crystallization behavior directly affects conductivity. Lastly, we studied a host-guest system of polymers aligned in straight silica mesoporous, with a goal of using confinement to understand the interplay between polymer microstructure and aggregation.
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.
Download or read book Understanding Structure function Relationship in Conducting Polymers and Plasmonic Structures written by Sachin Rane and published by . This book was released on 2006 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Structure function property Relationships in Conjugated Polyelectrolytes written by Andres Garcia and published by . This book was released on 2009 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: The attractive optoelectronic and mechanical properties of conjugated polymers have lead to intense research in understanding of their semiconducting properties and application in various devices. The properties of conjugated polymers are highly dependent and sensitive to intra- and inter-polymer chain contacts and new methods to manipulate and control these solution and solid state interactions and optoelectronic properties are thus continually being pursued. Conjugated polyelectrolytes (CPEs) are a class of conjugated polymers containing ionic substituents in which polymer chain interactions are known to be influence by long-range electrostatic interactions, not feasible in non-ionic conjugated polymers. Although, CPEs have exhibit device improvement when incorporated in light emitting and photovoltaic devices, the optical and particularly charge carrier transport properties are not fully understood. In this dissertation the influence of the ionic substituents on both the optical and charge transport properties of CPEs are systematically investigated in pursue of constructing concrete structure-function-property relationships that can be use as guidelines for the future design of CPEs that have tailored properties and function.
Download or read book Handbook of Conducting Polymers Fourth Edition 2 Volume Set written by John R. Reynolds and published by CRC Press. This book was released on 2019-11-14 with total page 1488 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last 10 years there have been major advances in fundamental understanding and applications and a vast portfolio of new polymer structures with unique and tailored properties was developed. Work moved from a chemical repeat unit structure to one more based on structural control, new polymerization methodologies, properties, processing, and applications. The 4th Edition takes this into account and will be completely rewritten and reorganized, focusing on spin coating, spray coating, blade/slot die coating, layer-by-layer assembly, and fiber spinning methods; property characterizations of redox, interfacial, electrical, and optical phenomena; and commercial applications.
Download or read book Semiconducting Polymers written by Raquel Aparecida Domingues and published by CRC Press. This book was released on 2021-06-25 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: Semiconducting polymers are of great interest for applications in electroluminescent devices, solar cells, batteries, and diodes. This volume provides a thorough introduction to the basic concepts of the photophysics of semiconducting polymers as well as a description of the principal polymerization methods for luminescent polymers. Divided into two main sections, the book first introduces the advances made in polymer synthesis and then goes on to focus on the photophysics aspects, also exploring how new advances in the area of controlled syntheses of semiconducting polymers are applied. An understanding of the photophysics process in this kind of material requires some knowledge of many different terms in this field, so a chapter on the basic concepts is included. The process that occurs in semiconducting polymers spans time scales that are unimaginably fast, sometimes less than a picosecond. To appreciate this extraordinary scale, it is necessary to learn a range of vocabularies and concepts that stretch from the basic concepts of photophysics to modern applications, such as electroluminescent devices, solar cells, batteries, and diodes. This book provides a starting point for a broadly based understanding of photophysics concepts applied in understanding semiconducting polymers, incorporating critical ideas from across the scientific spectrum.
Download or read book Functional Polymer Films 2 Volume Set written by Wolfgang Knoll and published by John Wiley & Sons. This book was released on 2013-02-12 with total page 1107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Very thin film materials have emerged as a highly interesting and useful quasi 2D-state functionality. They have given rise to numerous applications ranging from protective and smart coatings to electronics, sensors and display technology as well as serving biological, analytical and medical purposes. The tailoring of polymer film properties and functions has become a major research field. As opposed to the traditional treatise on polymer and resin-based coatings, this one-stop reference is the first to give readers a comprehensive view of the latest macromolecular and supramolecular film-based nanotechnology. Bringing together all the important facets and state-of-the-art research, the two well-structured volumes cover film assembly and depostion, functionality and patterning, and analysis and characterization. The result is an in-depth understanding of the phenomena, ordering, scale effects, fabrication, and analysis of polymer ultrathin films. This book will be a valuable addition for Materials Scientists, Polymer Chemists, Surface Scientists, Bioengineers, Coatings Specialists, Chemical Engineers, and Scientists working in this important research field and industry.
Download or read book Semiconducting Polymers written by Georges Hadziioannou and published by John Wiley & Sons. This book was released on 2006-12-15 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: The field of semiconducting polymers has attracted many researchers from a diversity of disciplines. Printed circuitry, flexible electronics and displays are already migrating from laboratory successes to commercial applications, but even now fundamental knowledge is deficient concerning some of the basic phenomena that so markedly influence a device's usefulness and competitiveness. This two-volume handbook describes the various approaches to doped and undoped semiconducting polymers taken with the aim to provide vital understanding of how to control the properties of these fascinating organic materials. Prominent researchers from the fields of synthetic chemistry, physical chemistry, engineering, computational chemistry, theoretical physics, and applied physics cover all aspects from compounds to devices. Since the first edition was published in 2000, significant findings and successes have been achieved in the field, and especially handheld electronic gadgets have become billion-dollar markets that promise a fertile application ground for flexible, lighter and disposable alternatives to classic silicon circuitry. The second edition brings readers up-to-date on cutting edge research in this field.
Download or read book Conjugated Polymers written by John R. Reynolds and published by CRC Press. This book was released on 2019-03-25 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers properties, processing, and applications of conducting polymers. It discusses properties and characterization, including photophysics and transport. It then moves to processing and morphology of conducting polymers, covering such topics as printing, thermal processing, morphology evolution, conducting polymer composites, thin films
Download or read book Semiconducting Polymers written by Christine Luscombe and published by Royal Society of Chemistry. This book was released on 2016-10-12 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nothing provided
Download or read book World Scientific Handbook Of Organic Optoelectronic Devices Volumes 1 2 written by and published by World Scientific. This book was released on 2018-06-29 with total page 908 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic (opto)electronic materials have received considerable attention due to their applications in perovskite and flexible electronics, OPVs and OLEDs and many others. Reflecting the rapid growth in research and development of organic (opto)electronic materials over the last few decades, this book provides a comprehensive coverage of the state of the art in an accessible format. It presents the most widely recognized fundamentals, principles, and mechanisms along with representative examples, key experimental data, and over 200 illustrative figures.
Download or read book Structure and Electronic Property Relationships in Chemically Doped Semiconducting Polymers and Polymer Photovoltaics written by Taylor Aubry-Komin and published by . This book was released on 2019 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work is focused on understanding how molecular-level structural control can improve charge carrier properties in -conjugated polymers. Conjugated polymers are characterized by extended conjugation along their backbone, making them intrinsically semiconducting materials that are of interest for a wide variety of flexible, thin-film electronic applications. Polymeric semiconductors possess advantages over inorganic materials such as being lightweight, low-cost and solution processable. However, due the disordered nature of conjugated polymers and their anisotropic transport, charge carrier dynamics can be highly sensitive to structural effects. The first chapter of this dissertation gives an introduction to conjugated polymers and their relevant applications as well as how tuning morphology and doping level can influence their charge carrier properties. The second introduces a technique, known as sequential processing (SqP), that affords control over polymer domain orientation when preparing polymer films as the active layer in optoelectronic devices. We show that conventional processing methods lead to disordered, isotropic polymer networks. By contrast, SqP can be used to preserve the preferred face-on chain orientation seen with some polymer materials, yielding advantages for photovoltaics and other devices via increased vertical hole mobility. Chapter 3 turns to molecular doping of conjugated polymers and studies the effects of a bulky boron cluster dopant used to modify the charge transport properties of conjugated polymers. The design of the dopant is such that it sterically protects core-localized electron density, resulting in shielding of the electron from holes produced on the polymer. This allows the charge carriers to be highly delocalized, as confirmed both spectroscopically and by AC-Hall effect measurements. The dopants allow for high carrier mobilities to be achieved even for non-crystalline polymers. The implication is that the counterion distance is the most important factor needed to produce high carrier mobility in conjugated polymers. In the last chapter, we study a series of boron cluster dopants in which the redox potential is tuned over a large range but the anion distance is fixed. In the last chapter, we study a series of boron cluster dopants in which the redox potential is tuned over a large range but the anion distance is fixed. This allows us to disentangle the effects of energetic offset in doping on the production of free carriers. We find that the redox potential not only affects the generation of free carriers, but also the infiltration of dopants into the polymer films.
Download or read book Design Synthesis and Structure Property Relationship Study of Polymer Field Effect Transistors written by Ting Lei and published by Springer. This book was released on 2015-01-05 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book summarizes Ting Lei’s PhD study on a series of novel conjugated polymers for field-effect transistors (FETs). Studies contain many aspects of polymer FETs, including backbone design, side-chain engineering, property study, conformation effects and device fabrication. The research results have previously scattered in many important journals and conferences worldwide. The book is likely to be of interest to university researchers, engineers and graduate students in materials sciences and chemistry who wish to learn some principles, strategy, and applications of polymer FETs.
Download or read book 50 Years of Structure and Bonding The Anniversary Volume written by D. Michael P. Mingos and published by Springer. This book was released on 2016-10-06 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical structure and bonding. The scope of the series spans the entire Periodic Table and addresses structure and bonding issues associated with all of the elements. It also focuses attention on new and developing areas of modern structural and theoretical chemistry such as nanostructures, molecular electronics, designed molecular solids, surfaces, metal clusters and supramolecular structures. Physical and spectroscopic techniques used to determine, examine and model structures fall within the purview of Structure and Bonding to the extent that the focus is on the scientific results obtained and not on specialist information concerning the techniques themselves. Issues associated with the development of bonding models and generalizations that illuminate the reactivity pathways and rates of chemical processes are also relevant. The individual volumes in the series are thematic. The goal of each volume is to give the reader, whether at a university or in industry, a comprehensive overview of an area where new insights are emerging that are of interest to a larger scientific audience. Thus each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years should be presented using selected examples to illustrate the principles discussed. A description of the physical basis of the experimental techniques that have been used to provide the primary data may also be appropriate, if it has not been covered in detail elsewhere. The coverage need not be exhaustive in data, but should rather be conceptual, concentrating on the new principles being developed that will allow the reader, who is not a specialist in the area covered, to understand the data presented. Discussion of possible future research directions in the area is welcomed. Review articles for the individual volumes are invited by the volume editors.
Download or read book Synchrotron Radiation in Materials Science written by Chunhai Fan and published by John Wiley & Sons. This book was released on 2018-05-29 with total page 846 pages. Available in PDF, EPUB and Kindle. Book excerpt: Meeting the long-felt need for in-depth information on one of the most advanced material characterization methods, a top team of editors and authors from highly prestigious facilities and institutions covers a range of synchrotron techniques that have proven useful for materials research. Following an introduction to synchrotron radiation and its sources, the second part goes on to describe the various techniques that benefit from this especially bright light, including X-ray absorption, diffraction, scattering, imaging, and lithography. The thrid and final part provides an overview of the applications of synchrotron radiation in materials science. bridging the gap between specialists in synchrotron research and material scientists, this is a unique and indispensable resource for academic and industrial researchers alike.
