![Versatile Route for Syntheses of [pi] Conjugated Polymers and Device Fabrication PDF](https://books.google.com/books/content/images/frontcover/7GRsYgEACAAJ?fife=w150-h200)
Author: Jayesh Ghewarchand BokriaPublisher:
ISBN:
Category :
Languages : en
Pages : 488
Book Description
Versatile Route for Syntheses of [pi] Conjugated Polymers and Device Fabrication
![Versatile Route for Syntheses of [pi] Conjugated Polymers and Device Fabrication PDF](https://books.google.com/books/content/images/frontcover/7GRsYgEACAAJ?fife=w80-h100)
Author: Jayesh Ghewarchand BokriaPublisher:
ISBN:
Category :
Languages : en
Pages : 488
Book Description
Design, Synthesis, and Application of Novel π-Conjugated Materials - Part II
Author: Haichang ZhangPublisher: Frontiers Media SA
ISBN: 2889716112
Category : Science
Languages : en
Pages : 70
Book Description
Design, Synthesis, and Application of Novel π-Conjugated Materials
Author: Haichang ZhangPublisher: Frontiers Media SA
ISBN: 2889664813
Category : Science
Languages : en
Pages : 126
Book Description
Design, Synthesis and Characterization of Self-assembling Conjugated Polymers for Use in Organic Electronic Applications
Author: Kathy Beckner WoodyPublisher:
ISBN:
Category : Organic electronics
Languages : en
Pages :
Book Description
Conjugated polymers comprise some of the most promising materials for new technologies such as organic field effect transistors, solar light harvesting technology and sensing devices. In spite of tremendous research initiatives in materials chemistry, the potential to optimize device performance and develop new technologies is remarkable. Understanding relationships between the structure of conjugated polymers and their electronic properties is critical to improving device performance. The design and synthesis of new materials which self-organize into ordered nanostructures creates opportunities to establish relationships between electronic properties and morphology or molecular packing. This thesis details our progress in the development of synthetic routes which provide access to new classes of conjugated polymers that contain dissimilar side chains that segregate or dissimilar conjugated blocks which phase separate, and summarizes our initial attempts to characterize these materials. Poly(1,4-phenylene ethynylene)s (PPEs) have been used in a variety of organic electronic applications, most notably as fluorescent sensors. Using traditional synthetic methods, asymmetrically disubstituted PPEs have irregular placement of side chains on the conjugated backbone. Herein, we establish the first synthetic route to an asymmetrically substituted regioregular PPEs. The initial PPEs in this study have different lengths of alkoxy side chains, and both regioregular and regiorandom analogs are synthesized and characterized for comparison. The design of amphiphilic structures provides additional opportunities for side chains to influence the molecular packing and electronic properties of conjugated polymers. A new class of regioregular, amphiphilic PPEs has been prepared bearing alkoxy and semifluoroalkoxy side chains, which have a tendency to phase separate. Fully conjugated block copolymers can provide access to interesting new morphologies as a result of phase separation of the conjugated blocks. In particular, donor-acceptor block copolymers that phase separate into electron rich and electron poor domains may be advantageous in organic electronic devices such as bulk heterojunction solar cells, of which the performance relies on precise control of the interface between electron donating and accepting materials. The availability of donor-acceptor block copolymers is limited, largely due to the challenges associated with synthesizing these materials. In this thesis, two new synthetic routes to donor-acceptor block copolymers are established. These methods both utilize the catalyst transfer condensation polymerization, which proceeds by a chain growth mechanism. The first example entails the synthesis of a monofunctionalized, telechelic poly(3-alkylthiophene) which can be coupled to electron accepting polymers in a subsequent reaction. The other method describes the first example of a one-pot synthesis of a donor-acceptor diblock copolymer. The methods of synthesis are described, and characterization of the block copolymers is reported.
Pi-conjugated Polymers: Synthesis and Application in Devices
Author: Venkataramanan SeshadriPublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages :
Book Description
The first part of the work embodied in this thesis is towards modifying the electronic band-gap of conjugated polymers consisting of thieno[3,4- b]thiophene as one of the repeat units. Two different approaches were undertaken to prepare copolymers of thieno[3,4-b]thiophene in order to accomplish this. First, a simple simultaneous electropolymerization of two monomers from a solution mixture, and second, an oligomeric approach, wherein an oligomer of thiophene and thieno[3,4-b]thiophene with cyanovinylene spacer units was electrochemically polymerized. Several electroanalytical and spectroscopic techniques were used to characterize these polymers. The major part of the thesis is focused on the electrochromic properties of conjugated polymers both in liquid and solid-state electrochemical cells. Several polymers reported in literature were re-evaluated on the basis of its photopic transmissivity. It is necessary that the contrast in a device is more pronounced at wavelengths, wherein the human eye is most sensitive at a given time of the day. At the same time, it is also important to take into account that the eye is sensitive to a broad spectral range. Hence, this photopic approach is very essential in understanding how the intensity of light can be controlled using electrochromic windows. Furthermore, the optical switchability of solid-state electrochromic windows were also studied. Several issues, such as electrodeposition onto indium doped tinoxide (ITO) surfaces with areas ≥ 30cm2, device stability were addressed during the course of this research. The photopically weighted contrast of the device as a whole was found to be enhanced using derivatives of 3,4-propylenedioxythiophene, belonging to the 3,4-alkylenedioxythiophene family. Finally, new device architecture was studied, wherein very low band-gap conjugated polymer with little/no visible electrochromism was used as the ion-storage layer in a dual polymer configuration. Colorimetric analysis of these devices was compared with the earlier devices incorporating a high band-gap anodically coloring conjugated polymer and low band-gap cathodically coloring polymer. These devices were found to be switching between a deep blue to a sky blue, which is a neutral color, as opposed to deep blue to yellow in the earlier configuration. Yellow filter is known to alter the way colors are perceived by the human eye.
Route Towards Incorporation of Pyrimidine in Conjugated Polymers and ß - Alkoxy Functionalized Poly(thiophene)
Author: Samodha Subhashini GunathilakePublisher:
ISBN:
Category : Aldol condensation
Languages : en
Pages : 302
Book Description
Conjugated polymers are promising materials that can be used in organic electronic devices, such as organic field effect transistors, organic solar cells, and organic light emitting diodes. They have some advantages over their inorganic counterparts such as solution proccesability, light weight, and easy device fabrication. These properties largely reduce the manufacturing cost of these devices. Different functional moieties can be incorporated in conjugated polymers to tune the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels, thus to control the band gap and to enhance their opto-electronic properties. These properties include good solubility, improved packing in solid state, and enhanced solar energy absorption. Pyrimidine has been incorporated in conjugated polymers due to its important properties such as electron withdrawing nature, pH sensitivity, and ability to participate in hydrogen bonding and coordinate various metal ions. Due to the electron deficient nature, pyrimidine polymers have low lying LUMO levels and have been applied in organic electronic devices as n-type semiconductors. Out of many functional moieties, thiophene ring is one of the most used units in conjugated polymers, because poly(thiophene)s possess good electronic properties. By incorporating alkoxy substituents on poly(thiophene)s the HOMO energy level of the polymers can be increased, resulting in low band gap polymers. These polymers are promising materials to be used in organic electronic devices. Chapter 1 discusses conjugated polymers used in organic electronic devices, their charge transport mechanisms, doping to improve the conductivity, and working mechanisms of organic electronic devices such as organic field effect transistors and solar cells. It also describes the potential use of these materials as a precursor for graphene. It further discusses pyrimidine conjugated polymers and poly(alkoxythiophene)s. Chapter 2 discusses the aldol condensation reactions to incorporate pyrimidine in conjugated polymers. It describes the synthesis, characterizations and optoelectronic properties of pyrimidine containing conjugated polymers. Chapter 3 discusses the synthesis of nitrogen containing graphitic materials by using pyrimidine conjugated polymers as the precursor. It describes the synthesis and characterizations of precursor polymers, nitrogen doped graphitic materials, and the application of these materials in polymer/graphene hybrid field effect transistors. Chapter 4 discusses the synthesis of poly(alkoxythiophene)s by McCullough method. It describes the synthesis, characterization of these polymers and oxidative doping to increase conductivity.
Conjugated Polymer Synthesis
Author: Yoshiki ChujoPublisher: John Wiley & Sons
ISBN: 3527632689
Category : Technology & Engineering
Languages : en
Pages : 333
Book Description
Edited and authored by top international experts, this first book on conjugated polymers with a focus on synthesis provides a detailed overview of all modern synthetic methods for these highly interesting compounds. As such, it describes every important compound class, including polysilanes, organoboron compounds, and ferrocene-containing conjugated polymers. An indispensable source for every synthetic polymer chemist.
Towards the Controlled Synthesis of Conjugated Polymers
Author: Paniz PahlavanluPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Organic semiconductors with varying physical and optoelectronic properties are readily obtained by incorporating different functional groups in conjugated polymers. While controlled chain-growth polymerization routes have been developed for a handful of these conjugated polymers, most conjugated polymers are still synthesized through step-growth methods that allow little to no control over the resulting polymers. Robust and versatile synthetic methodologies are needed to access conjugated polymers with unprecedented control and optimized properties. In Chapter 2, I describe a rapid and selective synthetic route to thionated naphthalene diimides (NDIs). Thionated NDIs exhibit improved electron mobilities and ambient stabilities. Thionation procedures, however, are lengthy, unselective, and low yielding. Polymeric analogues had not previously been reported due to incompatibilities between sulfur atoms and prevalent palladium catalysts. I illustrate that the rate and selectivity of thionation is drastically improved using steric control and highly efficient microwave irradiation. This methodology is readily applied to synthesize NDI-based polymers with varying degrees of thionation through post-polymerization modification. In Chapter 3, I investigate the anion-radical polymerization of parent and thionated, thiophene- and selenophene-flanked NDIs. Although NDI-based polymers exhibit among the highest electron mobilities for n-type conjugated polymers, their existing synthetic routes are still largely uncontrolled. Anion-radical polymerization provides a promising alternative, wherein thiophene- flanked NDIs have been shown to exhibit chain-growth polymerization. I show that thiophene- and selenophene-flanked NDIs undergo anion-radical polymerization, albeit through step-growth mechanisms. While thionated NDIs form anion-radical complexes and exhibit signs of catalyst insertion, they do not undergo further polymerization. In Chapter 4, I present the templated oxidative synthesis of conjugated polymers. Templated synthesis is a prevalent route to accessing biological and bioinspired polymers but has only sparingly been applied to the synthesis of conjugated polymers. I illustrate that well-defined macromolecular templates synthesized through ring-opening metathesis polymerization undergo subsequent oxidative coupling to form well-defined conjugated polymers. I apply this methodology to synthesize soluble, poly(3,4-ethylenedioxythiophene)-based polymers with controlled molecular weights and low dispersities. In Chapter 5, I summarize the main conclusions and outlook of this thesis work. Further optimization and expansion of the methodologies described herein could greatly impact the fields of conjugated polymers and organic electronic materials.
Conjugated Polymer Nanostructures for Energy Conversion and Storage Applications
Author: Srabanti GhoshPublisher: John Wiley & Sons
ISBN: 3527345574
Category : Technology & Engineering
Languages : en
Pages : 38
Book Description
A timely overview of fundamental and advanced topics of conjugated polymer nanostructures Conjugated Polymer Nanostructures for Energy Conversion and Storage Applications is a comprehensive reference on conjugated polymers for energy applications. Distinguished academic and editor Srabanti Ghosh offers readers a broad overview of the synthesis, characterization, and energy-related applications of nanostructures based on conjugated polymers. The book includes novel approaches and presents an interdisciplinary perspective rooted in the interfacing of polymer and synthetic chemistry, materials science, organic chemistry, and analytical chemistry. This book provides complete descriptions of conjugated polymer nanostructures and polymer-based hybrid materials for energy conversion, water splitting, and the degradation of organic pollutants. Photovoltaics, solar cells, and energy storage devices such as supercapacitors, lithium ion battery electrodes, and their associated technologies are discussed, as well. Conjugated Polymer Nanostructures for Energy Conversion and Storage Applications covers both the fundamental topics and the most recent advances in this rapidly developing area, including: The design and characterization of conjugated polymer nanostructures, including the template-free and chemical synthesis of polymer nanostructures Conjugated polymer nanostructures for solar energy conversion and environmental protection, including the use of conjugated polymer-based nanocomposites as photocatalysts Conjugated polymer nanostructures for energy storage, including the use of nanocomposites as electrode materials The presentation of different and novel methods of utilizing conjugated polymer nanostructures for energy applications Perfect for materials scientists, polymer chemists, and physical chemists, Conjugated Polymer Nanostructures for Energy Conversion and Storage Applications also belongs on the bookshelves of organic chemists and any other practicing researchers, academics, or professionals whose work touches on these highly versatile and useful structures.
Author: 陳宏揚