Дисертації з теми "Π-Conjugated Polymers"
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1
He, Yinghui. "Novel N-type Π-conjugated Polymers for all-polymer solar cells". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0651/document.
Повний текст джерелаАнотація:
Les cellules solaires organiques (OSC) apparaissent comme une technologie prometteuse pour les énergies renouvelables en raison de leur poids léger, leur grande flexibilité et leur processus de fabrication peu coûteux. Jusqu'à présent, la plupart des OPV ont utilisé des dérivés de Fullerene, tels que PCBM ou PC71BM, en tant qu'accepteur d'électrons dans la couche active, qui s'est avéré être un goulet d'étranglement pour cette technologie. Par conséquent, le développement d'accepteurs non-fullerene est devenu la nouvelle force motrice de ce domaine. Les cellules solaires tout-polymères (tous-PSC) qui ont les avantages de la robustesse, de la stabilité et de l'accessibilité ont déjà atteint PCE jusqu'à 9%. Ainsi, le développement de nouveaux matériaux accepteurs est impératif pour améliorer les performances de tous les PSCOrganic solar cells (OSCs) appear as a promising technology for renewable energy owing to their light weight, great flexibility and low-cost fabrication process. So far most of the OPV shave been using fullerene derivatives, such as PCBM or PC71BM, as the electron acceptor in the active layer, which have been proven to a bottleneck for this technology. Therefore,developing non-fullerene acceptors has become the new driving force for this field. All-polymer solar cells (all-PSCs) that have the advantages of robustness, stability and tunability have already achieved PCE up to 9%. Thus, developing novel acceptor materials is imperative for improving the performance of all-PSCs
2
Mask, Walker. "MODELING THE CONDENSED-PHASE BEHAVIOR OF Π-CONJUGATED POLYMERS". UKnowledge, 2019. https://uknowledge.uky.edu/chemistry_etds/120.
Повний текст джерелаАнотація:
It is well established that the morphology and physical properties of an organic semiconducting (OSC) material regulate its electronic properties. However, structure-function relationships remain difficult to describe in polymer-based OSC, which are of particular interest due to their robust mechanical properties. If relationships among the molecular and bulk levels of structure can be found, they can aid in the design of improved materials. To explore and detail important structure-function relationships in polymer-based OSC, this work employs molecular dynamics (MD) simulations to study various π-conjugated polymers in different environments. Two independent investigations are discussed in this work. One investigation examines how the purposeful disruption of the π-conjugated backbone to increase the chain flexibility impacts the chain structure and packing in the condensed phase. This is done by adding a conjugation break spacer (CBS) unit of one to ten carbons in length into the monomer structure of diketopyrrolopyrrole-based polymers. It is found that trends in the folding and glass structure follow the increase and the parity (odd versus even) of the CBS length. The second investigation analyzes a variety of polymers and small molecule acceptor (SMA) blends to observe the effects of changing the shape of either component and the physical properties of the material, as well as the structure of the polymer chains. It is found that the conjugated core, the side chains, and the planarity or sphericity each influence the density and diffusion of the materials made.
3
Riehn, Robert. "Optical near-field investigations of π-conjugated polymers". Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620723.
Повний текст джерела
4
Miyake, Junpei. "Synthesis of Novel Hybrid-Type π-Conjugated Polymers". 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/124548.
Повний текст джерела
5
Jadhav, R. "New π-conjugated materials for optoelectronic applications". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2019. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/4586.
Повний текст джерела
6
Ishida, Tamao. "Synthesis and functionalization of through-space π-conjugated polymers". 京都大学 (Kyoto University), 2006. http://hdl.handle.net/2433/144030.
Повний текст джерелаАнотація:
Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第12345号
工博第2674号
新制||工||1378(附属図書館)
24181
UT51-2006-J337
京都大学大学院工学研究科高分子化学専攻
(主査)教授 中條 善樹, 教授 増田 俊夫, 教授 檜山 爲次郎
学位規則第4条第1項該当
7
Adriana, Gelover Santiago Carmen. "π-conjugated polymers containing dithiafulvene and thioketene dimer units". 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144937.
Повний текст джерелаАнотація:
Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第11593号
工博第2539号
新制||工||1345(附属図書館)
23236
UT51-2005-D342
京都大学大学院工学研究科高分子化学専攻
(主査)教授 中條 善樹, 教授 増田 俊夫, 教授 伊藤 紳三郎
学位規則第4条第1項該当
8
Elmalem, Einat. "Synthesis of π-conjugated polymers via Suzuki cross-coupling polymerization". Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608242.
Повний текст джерела
9
Jagtap, Subodh Prakash. "Design and synthesis of and π-stacked conjugated oligomers and polymers". Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47574.
Повний текст джерелаАнотація:
Interchain interactions between π-systems have a strong effect on the properties of conjugated organic materials that find application in devices such as light emitting diodes (OLEDs), organic photovoltaics (OPVs), and field effect transistors (FETs). We have prepared covalently-stacked oligo(1,4-phenylene ethynylene)s and oligo(1,4-phenylene vinylene)s to study the influence of chain-chain interactions on the electronic structure of closely packed conjugated units. These serve as models for segments of conjugated materials in thin film devices. Extension of this concept has allowed us to prepare multi-tiered systems that display the influence of pi-stacking. The stacked architectures were prepared by multi-step synthesis of the scaffolds, followed by metal-catalyzed cross coupling reactions (Sonogashira, Heck, Suzuki couplings) to incorporate the conjugated oligomers. The optical and electrochemical properties of these stacked compounds and polymers were compared to their unstacked linear counterparts. These studies provide a platform for the exploration of the nature of charge carriers and excitons in a broad class of materials that have significant potential in addressing challenges in power generation, lighting and electronics.
10
Giraud, Lauriane. "Bis-vanillin substrates as source of π-conjugated polymers for organic electronic". Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0404.
Повний текст джерелаАнотація:
Ces travaux de thèse portent sur la synthèse de polymères π-conjugués biosourcés issus de la vanilline, visant des applications potentielles en électronique organique (photovoltaïque ou Organic Light Emitting Diode, OLED). Des polyazométhines de masses molaires élevées, issus de la copolymérisation entre la divanilline et différentes diamines, ont été obtenus par polymérisation sous irradiation micro-onde durant 5 minutes puis séchage à l’évaporateur rotatif. Ces derniers ont une absorbance dans le proche UV mais un chemin de conjugaison très court, comme l’a révélé l’analyse de molécules modèles. Pour améliorer ce chemin de conjugaison, une molécule à base de divanilline a été synthétisée avec les fonctions aldéhyde en position para par rapport à la liaison entre les deux cycles aromatiques. Cette para-divanilline, encore jamais décrite, a été utilisée pour la synthèse de polyazomethines. Ces derniers présentent également un court chemin de conjugaison en raison de l’encombrement stérique entre les deux groupes phényle. Une dernière famille de polymère a alors été étudiée : les polythiazolothiazoles à base de divanilline. Ces polymères présentent des propriétés d’émission qui se caractérisent par une émission dans le bleu en solution et dans le jaune à l’état de film. Des molécules modèles à base de benzothiazole ont également été synthétisées et présentent un rendement quantique de fluorescence de 20% ainsi qu’un empilement π en « chevrons », leur conférant un fort potentiel pour diverses applications en électronique organiqueThe objective of this PhD is to synthesize π-conjugated bio-based polymers from vanillin, with potential applications in the field of organic electronic (photovoltaic, Organic Light Emitting Diode, OLED). Polyazomethines with high molar masses were obtained via the copolymerization of divanillin with various diamines. This polycondensation was performed in 5 minutes under microwave irradiation, followed by solvent removal using a rotary evaporator. Divanillin-based polyazomethines absorb in the near-UV range but have a short conjugation pathway, as revealed investigations on model compounds. To improve this conjugated pathway, a divanillin-based molecule bearing aldehyde functions in para positions with respect to the link between the rings, was designed. This so-called para-divanillin, never reported before, was copolymerized to yield polyazomethines. These latter polymers also have a short conjugation pathway due to steric hindrance between the two aromatic rings of the para-divanillin skeleton. A last family of divanillin-based polymers was thus investigated: polythiazolothiazoles. The latter exhibit specific emission properties as they emit in the blue range in solution and in the yellow range in films. Benzothiazole-based model compounds were also synthesized and exhibited a fluorescence quantum yield of 20% and “herringbone-like” π-stacking, giving them a strong potential for various organic electronic applications
11
Matsumi, Noriyoshi. "Generation of a New Class of Org anoboron π-Conjugated Polymers". Kyoto University, 2000. http://hdl.handle.net/2433/180980.
Повний текст джерела
12
Liu, Ruiyuan. "Synthesis and properties of amino acid-derived π-conjugated helical polymers". 京都大学 (Kyoto University), 2009. http://hdl.handle.net/2433/126508.
Повний текст джерелаАнотація:
Kyoto University (京都大学)0048
新制・課程博士
博士(工学)
甲第14944号
工博第3171号
新制||工||1476(附属図書館)
27382
UT51-2009-M858
京都大学大学院工学研究科高分子化学専攻
(主査)教授 澤本 光男, 教授 木村 俊作, 准教授 三田 文雄
学位規則第4条第1項該当
13
Wada, Naoki. "Cyclophane-containing polymers : through-space and through-bond π-conjugated system". 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136250.
Повний текст джерела
14
Sobczak, Quentin. "Synthesis of new amino-containing π-conjugated polymers via dimerization of acyclic aminoarylcarbenes". Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0208.
Повний текст джерелаАнотація:
Dans cette thèse, la synthèse de polymères semi-conducteurs par une voie originale n’utilisant pas de métaux, afin de les intégrer dans des dispositifs électroniques organiques comme les OLED (Organic light emitting diode) a été developpée. Le but est de développer et d’optimiser une nouvelle méthode de synthèse en s’appuyant sur des bis-aminoarylcarbènes acyclique en tant que blocs constructeurs afin d’obtenir de nouveaux polymères PPV-like. Dans un premier temps, la réaction de dimérisation est étudiée au niveau moléculaire avec la synthèse et caractérisations de diaminoalcènes obtenu à partir de carbènes acycliques monofonctionnels. Le mécanisme et la sélectivité de cette réaction de dimérisation ont également été examiné par voies expérimentales et théoriques. Dans un deuxième temps, la réaction de dimérisation a été étendu au niveau macromoléculaire avec la synthèse et caractérisations de nouveaux PPV-like polymères contenant des fonctions amino en α de la double liaison. Par la suite, l’influence de ces groupements amino sur les propriétés optoélectroniques de ces N-PPV une fois modifiés chimiquement a pu être étudié. Enfin, les caractéristiques particulières des diaminoalcènes synthétisés au cours cette thèse ont permis une étude préliminaire sur leurs applications potentielles en tant que catalyseur organiques dans la réaction de polymérisation radicalaire par transfert d’atomesIn this thesis, the study focuses on the synthesis of semi-conducting polymers by an original pathway free from metals, in order to integrate them into organic electronic devices such as OLEDs (Organic light emitting diodes). The aim is to develop and optimize a new methodology using acyclic bis-aminoarylcarbenes as building blocks to synthesize new PPV-like polymers. First, the dimerization reaction is studied at a molecular level with the synthesis and characterization of diaminoalkenes obtained from monofunctional acyclic aminoarylcarbenes. The mechanism and the selectivity of this dimerization reaction is also investigated experimentally and theoretically. In a second step, the dimerization reaction was extended at a macromolecular level with the synthesis and characterization of new PPV-like polymers containing amino functions in α of the double bond. Subsequently, the influence of these chemically modified amino groups on the optoelectronic properties of these N-PPVs has been studied. Finally, the specific characteristics of the diaminoalkenes synthesized during this thesis has allowed a preliminary study on their potential applications as organocatalysts in the atom transfer radical polymerization reaction
15
Sogawa, Hiromitsu. "Synthesis and Properties of Amino Acid-derived Optically Active π-Conjugated Polymers". 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/174959.
Повний текст джерела
16
Ahmed, Syed Zaka. "Approaches to ferrocene-containing π-conjugated polymers : synthesis, characterisation, structural and electrochemical studies". Thesis, University of St Andrews, 1998. http://hdl.handle.net/10023/14783.
Повний текст джерелаАнотація:
The aim of the work carried out for this thesis was to explore way to synthesise and characterise π-conjugated ferrocene containing polymers by using a condensation polymerization technique. Three types of such compounds were investigated: namely polyquinoxalines (pox)s, polyimines (PJ)s and polyketones (PK)s. The work was started by carrying out the same reactions on small molecules, in order to understand the reaction pathway and to establish the reaction conditions and to obtain the benchmark characterisation data. Initially monofunctional ferrocene derivatives were prepared and condensed with mono- and bi-functional organic molecules, and bifunctional ferrocene derivatives were synthesised and condensed with mono functional organic molecules, to yield the small molecular condensation products. When the reaction conditions had been optimised the same reactions were extended to bifunctional ferrocene derivatives and bifunctional organic entities to obtain the co-polymers. After citing the relevant references in chapter one, the synthesis of mono- and bi-functional ferrocene containing diketones (FcCOCOK) by the oxidation of the synthesised mono-ketones is described in chapter 2 and their condensation with unsubstituted and substituted organic di- and tetra-amines to produce ferrocene containing mono-, bis - and poly-quinoxalines is described in chapter 3. The crystal structures of some of the compounds are also determined as definitive proof of characterisation. The attempted oxidation of ferrocenyl monoketones (FcCH2COR) to diketones by using selenium dioxide produced the coupled, dimeric, products (FcCHCOR)2. Electrochemical studies of the synthesised quinoxalines were also carried out. In chapter 4 are described the condensation of ferrocene aldehyde (FcCHO) and dialdehyde [(Fcd(CH0)2] with aromatic amines to yield ferrocene containing mono-, bis-and poly-imines. Chapter 5 deals with the synthesis and characterisation of ferrocene containing mono-, bis- and poly ketones synthesised by Friedel Crafts acytation reactions. The molecular weights of the synthesised ferrocene-containing polymers are also estimated with the help of hi NMR spectra.
17
Oriou, Jules. "Synthesis and structure-properties relationship of alternated π-conjugated copolymers". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-01070649.
Повний текст джерелаАнотація:
Tout au long du siècle dernier, l'électronique s'est révélé être un progrès technologique majeur, et ses applications sont tellement nombreuses qu'elles ont envahi notre vie de tous les jours. De par leurs propriétés bien spécifiques, les semi-conducteurs organiques représentent une remarquable alternative aux matériaux inorganiques utilisés actuellement. Cependant, leurs propriétés électriques peuvent être limitées, et l'efficacité des dispositifs composés de tels matériaux ne permet pas encore de rivaliser avec ceux basés sur des matériaux inorganiques. Dans ce contexte, ce travail de thèse a pour objectif de synthétiser et caractériser de nouveaux polymères conjugués et d'étudier leurs propriétés, dans le but d'ajouter de nouveaux matériaux au déjà riche catalogue de polymères semi-conducteurs disponibles, ainsi que de permettre une meilleure compréhension de la relation structure-propriétés dans les systèmes conjugués. Des copolymères alternés composés de motifs carbazole, benzothiadiazole ou encore squaraine ont été synthétisés et caractérisés. De plus, des polymérisations originales et sans catalyseurs métalliques ont été développées.
18
Wang, Zhendong. "Photophysics of Single-walled Carbon Nanotubes and Thin-film Conjugated Polymers Within π-electron Model". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195107.
Повний текст джерелаАнотація:
Electron-electron interaction effects play important role in the photophysics of complex organic materials such as π-conjugated polymers and single-walled carbon nanotubes. Our theoretical work within a π-electron model captures the essential mechanism of the photophysics in these apparently different π-conjugated systems. In both polymer and nanotube systems, we not only explain existing experiments but also make testable predictions. In the area of π-conjugated polymers, we develop a theory of the electronic structure and photophysics of interacting chains to understand the differences between solutions and films. While photoexcitation generates only the optical exciton in solutions, the optical exciton as well as weakly allowed excimers are generated in films. Photoinduced absorption in films is primarily from the lowest excimer. We are also able to explain peculiarities associated with photoluminescence, including delayed photoluminescence and its quenching by electric field. We thereby resolve controversies in the field that are more than a decade old. In the area of single-walled carbon nanotubes, we have investigated the exciton theory of the electronic structure of both semiconducting and metallic nanotubes. We are able to determine quantitatively the exciton energies and exciton binding energies of the nanotubes, in both longitudinal and transverse directions. Our estimate of longitudinal exciton energies and exciton binding energies of semiconducting tubes are the best quantitative fits to the experimental results to date. We also make predictions that the longitudinal exciton binding energies of metallic tubes are comparable to those of semiconducting tubes, in contradiction to recently published results. Our work demonstrates a universality in the photophysics of S-SWCNTs and PCPs that arises from their common quasi-one-dimensionality and π-conjugation.
19
Carson, Bradley Edward. "Synthesis and properties of π-stacked phenylene ethynylene oligomers with a 1,8- substituted naphthalene bridging scaffold". Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41074.
Повний текст джерелаАнотація:
The field of molecular electronics includes the study of conjugated oligomers and
polymers that have significant potential for use in devices such as light emitting diodes
(LEDS), field effect transistors (FETS), and photovoltaic solar cells. These materials may
replace inorganic semiconductors in these devices, Achieving better device performance
through lowering the band-gap and achieving higher field effect mobilities will benefit
from a greater fundamental understanding of charge transfer through the aromatic
subunits. π-stacking of segments of conjugated polymers has been identified as a key
feature that influences the charge transfer through semiconducting organic materials.
Optimizing the molecular architecture of conjugated polymers has the potential to
provide materials with better charge mobility. While devices might benefit from materials
that take advantage of π-stacking, access to π-stacked structures presents a synthetic
challenge. 1,8-Disubstituted naphthalenes may serve as simple covalent bridging
scaffolds which might hold conjugated oligomers in a π-stacked arrangement. The
research described in this thesis focuses on the synthesis of well-defined phenylene
ethynylene oligomers coupled to naphthalene to serve as experimental models of closely
π-stacked aromatic units in conjugated polymers. The π-stacked molecules reported in
this dissertation are characterized by NMR, IR, and mass spectrometry. The effects of π-
stacking on the structure and behavior of conjugated oligomers are determined by X-ray
crystallography, spectroscopy, and electrochemistry.
20
Chen, Xufang. "Synthesis and Characterization of Molecules and π-Conjugated Materials Containing Low-Coordinate Phosphorus". Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1102137178.
Повний текст джерела
21
Dahlstrand, Christian. "Ground and Excited State Aromaticity : Design Tools for π-Conjugated Functional Molecules and Materials". Doctoral thesis, Uppsala universitet, Fysikalisk-organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-173115.
Повний текст джерелаАнотація:
The main focus of this thesis is on the aromaticity of the ground state and electronically excited states of π-conjugated molecules and polymers, as well as how aromaticity is connected to their properties. The electronic structures of polybenzenoid hydrocarbons (PBHs) were explored through density functional theory (DFT) calculations and the π-component of the electron localization function (ELFπ). The study revealed how the π-electronic structure is influenced by the fusion of double bonds or benzene rings to the PBHs. We also demonstrated that the π-electrons of benzene extend to accommodate as much aromaticity as possible when bond length distorted. The aromatic chameleon property displayed by fulvenes, isobenzofulvenes, fulvalenes, bis(fulvene)s, and polyfulvenes were investigated using DFT calculations. The tria-, penta-, and heptafulvenes were shown to possess ionization energies and electron affinities which can be tuned extensively by substitution, some of which even outperform TTF and TCNQ, the prototypical electron donor and acceptor, respectively. The singlet-triplet energy gap of pentafulvenes can be tuned extensively by substitution to the point that the triplet state is lower than the singlet state and thus becomes the ground state. The ELFπ of isobenzofulvene shows that the benzene ring in an electronically excited state can be more aromatic than the corresponding ring in the ground state. We have shown that the 6-ring of [5.6.7]quinarene is influenced by a Hückel aromatic resonance structure with 4n+2 π-electrons in the excited quintet state. The bis(fulvene)s which are composed of a donor type heptafulvene and an acceptor type pentafulvene, retain the basic donor-acceptor properties of the two fragments and could function as compact donor-acceptor dyads. A few of the designed polyfulvenes were found to have band gaps below 1 eV at the PBC-B3LYP/6-31G(d) level. Various 2,7-disubstituted fluorenones and dibenzofulvenes were synthesized and their excited state properties were investigated by absorption spectroscopy and time-dependent DFT calculations. It was found that the 1A → 1B transition of ππ* character can be tuned by substitution in the 2,7-positions. The 2,7-bis(N,N-dimethyl) derivatives of fluorenone and dibenzofulvene displayed low energy transitions at 2.18 and 1.61 eV, respectively, in toluene.
22
Mohammad, Mohammad M. Qaid [Verfasser], Georg Gutachter] Schmidt, Georg [Gutachter] Woltersdorf та Axel [Gutachter] [Hoffmann. "Spin pumping and inverse spin Hall effect in π-conjugated polymers / Mohammad M. Qaid Mohammad ; Gutachter: Georg Schmidt, Georg Woltersdorf, Axel Hoffmann". Halle (Saale) : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2020. http://d-nb.info/1214641121/34.
Повний текст джерела
23
Kolhe, N. B. "Design and synthesis of novel π-conjugated molecules and polymers based on naphthalene and perylene diimides and their application in organic electronics". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2015. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2026.
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24
Josse, Pierre. "Matériaux dérivés de colorants pour le photovoltaïque organique." Thesis, Angers, 2018. http://www.theses.fr/2018ANGE0048.
Повний текст джерелаАнотація:
Le développement du photovoltaïque organique (OPV) depuis une vingtaine d’années a permis une hausse significative des rendements de photoconversion qui atteignent aujourd’hui 14 %. Ces progrès résultent à la fois de l’optimisation de l’architecture des cellules solaires organiques (OSCs) ainsi que de la mise au point de matériaux donneurs (D) et accepteurs (A) d’électrons performants. Cependant, la complexification notable des voies de synthèse de ces matériaux limite la production à grande échelle de modules OPV en raison de coûts de production élevés et de génération de nombreux déchets. Dans ce contexte et après un premier chapitre retraçant l’historique de l’OPV et les découvertes ayant contribuées à son succès, un deuxième chapitre traite de l’utilisation d’un colorant simple, le dicétopyrrolopyrrole (DPP), dans des matériaux de type p ou n. De nouveaux accepteurs moléculaires ont été synthétisés et l’impact de la nature des chaines solubilisantes et de l’espaceur π-conjugué sur leurs propriétés optoélectroniques est présenté. Un nouveau copolymère de DPP et de spirobifluorène, facilement accessible par des voies de synthèse plus respectueuses de l’environnement, a aussi été développé et caractérisé lors de ce travail et ses performances photovoltaïques sont détaillées. Un troisième chapitre se focalise sur le benzothioxanthène imide (BTXI), bloc encore méconnu dans le domaine de l’électronique organique. Les propriétés électroniques de ce dernier ont été caractérisées et, après une optimisation de sa voie de synthèse, des dérivés de BTXI ont été intégrés avec succès dans des dispositifs de type OSCs et transistors organiques en couche mince (OTFTs)Intense development of organicphotovoltaics (OPVs) in the last twenty years led toincreasing photoconversion efficiencies, which are nowabout 14 %. Electron donating (D) and electronaccepting (A) materials used in such solar cells havereceived considerable attention from the academicsaround the world and are still continuously improved.However, those performing materials requirenumerous synthetic steps and the use of toxicchemicals to be produced, which jeopardize their futurecommercialization.In this context, after a first chapter reviewing recentprogresses in OPV, a second chapter will focus on asimple dye, namely the diketopyrrolopyrrole (DPP) andits use in p and n type materials.New molecular DPP-based acceptors weresynthetized and the impact of the solubilizing chainsalong with the -conjugated spacer on theirphotovoltaic properties are discussed. Then, a newDPP and spirobifluorene (SBF) based copolymer wassynthetized by a more environmentally friendlysynthetic route and its photovoltaic properties aredetailed.A third chapter focuses on the benzothioxantheneimide (BTXI), a building block that has not yettriggered much interest in the organic electronicscommunity. Electronic properties of the latter werecharacterized and, after its synthetic pathway wasoptimized, new BTXI based molecular materials weresynthesized and used in organic solar cells andorganic thin-film transistors (OTFTs)
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Nunes, Domschke Tamara. "P-doped semiconducting polymers : process optimization, characterization and investigation of air stability." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSES020.
Повний текст джерелаАнотація:
Les semi-conducteurs organiques (OSCs) sont des matériaux prometteurs pour la production à faible coût de dispositifs électroniques imprimés flexibles et de grandes surfaces. Dans ce contexte, le dopage moléculaire permet de contrôler les propriétés électriques des OSC, offrant un outil puissant pour améliorer les performances de différents dispositifs électroniques. Malgré les progrès dans la compréhension fondamentale du mécanisme de dopage et de leurs procédés, la stabilité des OSC dopés p ont reçu peu d'attention. Or, la stabilité de l'état dopé p en présence d'oxygène et d'humidité est un facteur crucial pour l'intégration de couches dopées dans des dispositifs organiques.Dans cette thèse, nous avons étudié le dopage moléculaire de semi-conducteurs polymères désordonnés et la stabilité du dopage p en présence d'oxygène et d'espèces liées à l'eau. PBDTTT-c et RRa-P3HT ont été utilisés comme matrice de polymères et F4TCNQ et Mo(tfd-COCF3)3 comme dopants de type p. Les paramètres du procédé de dopage ont été soigneusement étudiés pour obtenir un dopage contrôlé et optimiser les propriétés électriques. L'impact de la concentration de dopant a été étudié en termes de propriétés électriques (conductivité), optiques (UV-Vis-NIR) et structurelles (GIWAXS).La stabilité de l'état dopé p a été analysée en surveillant l'évolution des signatures de dopage sous trois atmosphères différentes : l'argon, l'air anhydre et l'air ambiant. Des analyses XPS ont été effectuées pour étudier l'impact de l'exposition à l'air sur l'état chimique des couches dopées p. Des simulations ont été utilisées pour étayer nos résultats.Les résultats actuels ont mis en évidence la présence d'un mécanisme de dédopage important pour les polymères semi-conducteurs dopés-p en présence d'espèces liées à l'eauOrganic semiconductors (OSCs) are promising materials for low-cost, flexible, large-area production of printed electronic devices. In this context, molecular doping allows controlling the electrical properties of OSCs, offering a powerful tool to improve the performances of different electronic devices. Despite the progress in the fundamental understanding of the doping mechanism and processing techniques, stability aspects of p-doped OSCs have received little attention. Nevertheless, the stability of the p-doped state in the presence of oxygen and humidity is a crucial factor to be investigated for the integration of doped layers in organic devices.In this thesis, we have studied the molecular doping of disordered polymer semiconductors and the stability of the p-doped state in the presence of oxygen and water-related species. PBDTTT-c and RRa-P3HT were used as polymer hosts and F4TCNQ and Mo(tfd-COCF3)3 as p-dopants. The process conditions have been carefully studied to achieve controlled doping and to optimize the electrical properties. The impact of the dopant concentration was investigated in terms of electrical (conductivity), optical (UV-Vis-NIR) and structural (GIWAXS) properties of doped layers.The stability of the p-doped state was investigated by monitoring the evolution of the doping signatures under three different atmospheres: argon, anhydrous air, and ambient air. XPS analyses were carried out to investigate the impact of air exposure on the chemical state of p-doped layers. Simulations have been used to support our findings.Present results highlighted the presence of an important dedoping mechanism for p-doped semiconducting polymers in the presence of water-related species
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Watanabe, Hiroyuki. "Azaphenalene-based π-Conjugated System". Kyoto University, 2020. http://hdl.handle.net/2433/253304.
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Tominaga, Masato. "Functional π-Conjugated Materials Based on Structure of o-Carborane". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188607.
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Gon, Masayuki. "Synthesis of Novel π-Conjugated Compounds Based on Tetrasubstituted [2.2]Paracyclophane". 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/204583.
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Chevrier, Michèle. "Towards new π-conjugated systems for photovoltaic applications". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT206/document.
Повний текст джерелаАнотація:
Le développement des énergies renouvelables est aujourd’hui devenu un enjeu mondial majeur comme alternative aux énergies fossiles dans la production d'énergie. Parmi elles, l’énergie solaire est considérée comme la source la plus prometteuse, permettant de couvrir l’ensemble des besoins énergétiques liés à l’activité humaine. Les cellules photovoltaïques les plus performantes aujourd’hui, entre 16 et 18 % en modules, sont composées de silicium, un semi-conducteur inorganique. Cependant, leur coût de production élevé a nécessité le développement de matériaux alternatifs moins couteux. Parmi les voies explorées, les cellules solaires organiques ont émergé comme une alternative prometteuse pour produire l’électricité à faible coût. Le sujet de cette thèse s’intègre dans ce contexte de recherche. Deux types de cellules solaires ont été étudiés : les cellules à hétérojonction en volume (BHJ) et sensibilisées au colorant (DSSCs). Le courant photogénéré repose généralement (i) dans les cellules BHJ, sur le transfert entre de charge entre un polymère donneur et un accepteur d’électrons (fullerène), tels que le couple poly(3-hexyl)thiophène (P3HT) et [6,6]-phényl-C61-butanoate de méthyle (PCBM), et (ii) dans les DSSCs, la sensibilisation de la surface d’un semi-conducteur inorganique tel que l’oxyde de titane par un colorant et la présence d’un électrolyte, jouant le rôle de médiateur redox. Bien qu’ayant atteint des rendements de photoconversion respectifs de 5 et 13 %, ces cellules nécessitent des améliorations pour une commercialisation à grande échelle. Tout d’abord, les performances des cellules BHJ à base de P3HT sont considérablement limitées par sa faible absorption, ne couvrant pas la globalité du spectre solaire. Afin de palier ce problème, nous avons combiné le P3HT avec des chromophores, i.e. des porphyrines, ayant une absorption plus étendue. Ensuite, pour assurer une meilleure extraction des charges au sein du dispositif, une couche interfaciale cathodique à base de polyélectrolytes pi-conjugués a été ajoutée. Enfin, des colorants extraits de la biomasse ont été préparés afin de remplacer les colorants coûteux à base de ruthénium. En outre, les électrolytes liquides étant volatils et corrosifs, ce qui limite considérablement la stabilité des DSSCs, des électrolytes solides à base de polymères ont été étudiés comme alternativeAmong renewable energies, the sunlight has by far the highest theoretical potential to meet the worldwide need in energy. Photovoltaic devices are thus currently the subject of intense research for low-cost conversion of sunlight into electrical power. In particular, organic photovoltaics have emerged as an interesting alternative to produce electricity due to their low manufacturing cost compared to silicon solar cells, their mechanical flexibility and the versatility of the possible chemical structures. In this dissertation, we focused our research on the development of new organic pi-conjugated materials for organic solar cells applications. Two types of solar cells have been studied during this work: bulk heterojunction and dye-sensitized solar cells. The charge transfer leading to the photocurrent is usually based on (i) a polymer donor and a fullerene acceptor in BHJ solar cells, such as the widely studied poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) materials and (ii) a metal oxide (titanium oxide) sensitized with a dye and an electrolyte in DSSCs. Despite power conversion efficiencies have reached 5 and 13 % respectively for these two types of devices, they still display several drawbacks that limit their commercialization. P3HT displays a narrow absorption of the solar spectrum thus limiting the conversion efficiency. To overcome this limitation, we combined P3HT with chromophores, i.e. porphyrins, having an extending absorption. Then, to ensure better charge transfer and extraction within the device, a cathode interfacial layer based on cationic pi-conjugated polyelectrolytes was added. Finally, dyes extracted from the biomass (chlorophyll a derivatives) were synthesized to replace the expensive ruthenium dyes in DSSCs. Since liquid electrolytes are volatile and corrosive, which considerably limit the DSSCs stability, solid polymer electrolytes were also developed as an alternative
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Fahsi, Karim. "Différentes stratégies d’auto-assemblage de dérivés diacétyléniques porteurs d’hétérocycles azotés aromatiques : application à la synthèse de matériaux." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20128/document.
Повний текст джерелаАнотація:
Les polydiacétylènes sont des polymères π-conjugués, obtenus par polymérisation topochimique à l'état solide de motifs diacétyléniques, sous l'effet d'un stimulus thermique ou photochimique. Depuis leur découverte en 1969 par Wegner, les polydiacétylènes ont fait l'objet de nombreux travaux de recherche. Ces travaux ont consisté tout d'abord à élucider le mécanisme de polymérisation, puis à étudier les diverses propriétés photophysiques, optiques, et électroniques des polymères. Néanmoins, la plupart des diacétylènes étudiés ne possédaient pas de substituants susceptibles d'être modifiés chimiquement. Le premier chapitre de cette thèse décrit la synthèse de nouvelles molécules diacétyléniques symétriques comportant des groupements azoles, et l'étude de leur polymérisation à l'état solide. La modification de l'organisation des motifs diacétyléniques.par interaction avec des molécules capables de former des liaisons hydrogène, et l'incorporation de ces motifs dans des matériaux hybrides organiques-inorganiques de type,. MOF ont également été examinées.Dans le deuxième chapitre, nous nous sommes intéressés aux composés diacétyléniques dicationiques fonctionnalisés par des groupements triéthylammoniums, imidazoliums et benzimidazoliums. La synthèse de ces composés, leur caractérisation spectroscopique, et cristallographique, ainsi que l'étude de leur réactivité thermique et photochimique ont été réalisées.Dans le troisième chapitre, nous proposons une méthode directe de préparation de carbone dopé à l'azote par pyrolyse des molécules diacétyléniques neutres, ainsi que la synthèse de carbone mésoporeux en présence d'un sel métallique. Un autre aspect de ce chapitre est l'optimisation des teneurs en azote en utilisant comme précurseurs les composés diacétyléniques dicationiques, associés à des anions riches en azote, notamment l'anion dicyanamide [dca] et tricyanométhide [tcm]Diacetylenes (DA) are unusual molecules owing to their ability to polymerize in the solid state. Such a polymerization is triggered off thermally or photochemicaly, and leads to the formation of enyne structures. Since their discovery in 1969 by Wegner, polydiacetylenes (PDA) have been the focus of much attention. Initially, many studies were devoted to elucidating the mechanism of polymerization, then assessment of the diverse photophysical, optical, and electronic properties of the polymers became the main goal. Yet, the vast majority of the DA that were studied did not possess substituents that could be modified chemicallyThe first chapter describes the synthesis of new symmetrical diacetylenic molecules functionalized with azole substituents and the study of the polymerization of these compounds in the solid state. Then, we present the modification of the organization of these diacetylenes by the interaction with molecules capable of forming hydrogen bonds, and the use of these molecules as ligands for the synthesis of Metal Organic Frameworks (MOF).The second chapter is devoted to the synthesis, characterization and crystallographic study of ionic diacetylenic compounds bearing triethylammonium, imidazolium and benzimidazolium groups. The photochemical and thermal behaviors of these DA have been tested.In the third chapter, we propose a straightforward route to N-doped graphitic carbon by direct pyrolysis of neutral diacetylenic precursors, and investigate the possibility of forming porous materials by adding a metal salt as a catalyst. Furthermore, another aspect of this chapter was to optimize the nitrogen content of these materials by using dicationic DA with N-rich anions, e.g. dicyanamide [dca] and tricyanomethide [tcm]
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Popere, Bhooshan Chandrakant. "BODIPY-based panchromatic π-conjugated polymers for organic photovoltaics". 2013. https://scholarworks.umass.edu/dissertations/AAI3589138.
Повний текст джерелаАнотація:
In a highly interdisciplinary field, such as organic photovoltaics (OPVs), developing a predictive understanding of the relationship between molecular structures, morphology of the photoactive layer and the ultimate device performance is the key to unlocking the vast potential of this field. Although isolated examples of high-performance organic molecules are prevalent in the literature, the reasons for their superior performance are not well understood. The function of an OPV device is dependent of four key processes: (i) light absorption, (ii) charge separation, (iii) charge transport, and (iv) charge collection. While the first three are material-dependent factors, charge collection depends on the nature of the interfaces involved. We have thus investigated a new class of semiconductor molecules based on BODIPY dyes with the aim of understanding how variations in the molecular structure affect the optoelectronic and transport properties of the molecules. First-generation pi-conjugated polymers based on the BODIPY core possess broad and intense absorption spectra. Additionally, the frontier molecular orbital (FMO) energy levels of the polymers can be tuned by a judicious choice of the comonomers. Electron-deficient comonomers with electron affinities higher than that of the BODIPY core, predominantly afford n-type polymers. A unique feature of these semiconductors is their panchromatic absorption spectrum that spans throughout the visible region. Thus these polymers can be considered to be potential electron acceptors in all-polymer solar cells. Copolymerization of BODIPY with electron-rich comonomers, on the other hand, only results in p-type semiconductors. Furthermore, the highest occupied molecular orbital (HOMO) of these polymers is found to correlate with the ionization potential of the electron-rich monomer. Having said that, the lowest unoccupied molecular orbital (LUMO) energy level does not change. Thus for the first time, a correlation between theoretical calculations and experimental observations has been demonstrated for predicting the FMO energy levels of BODIPY-based semiconducting polymers. Second-generation copolymers based on an unsubstituted BODIPY core retain the broad absorption characteristics of the first-generation polymers. In addition, due to reduced electron density on the BODIPY core, the HOMO energy level of the resulting polymers is reduced thereby imparting enhanced oxidative stability to these polymers. Charge transport measurements through thick films (∼1 micron) reveal only p-channel activity with hole mobilities comparable to some of the high-performance polymers reported in literature. Preliminary bulk-heterojunction OPV devices fabricated with these polymers show modest power conversion efficiencies. We believe that understanding the morphology of the active layer in relation to the polymer structure will help improve future molecular designs and eventually, device performance.
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Keivanidis, Panagiotis E. [Verfasser]. "Electronic energy transfer processes in π-conjugated [pi-conjugated] polymers / Panagiotis E. Keivanidis". 2005. http://d-nb.info/975973452/34.
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Chen, Hung-Yang, та 陳宏揚. "Design and Synthesis of π-Conjugated Polymers for Organic Optoelectronics". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/93717472538407026970.
Повний текст джерелаАнотація:
博士國立臺灣大學
化學研究所
100
Polymer-based organic light-emitting diode (OLED) and organic photovoltaic (OPV) are two most extensively studied fields in polymer-based optoelectronics. In this thesis, three different series of π-conjugated copolymers have been designed and synthesized for OLED and OPV applications, respectively. The correlations between chemical structures and device performances have been studied and discussed in the context. For OLED application, a series of new 9,10-diphenylanthracene-based, 2,6-linked blue-light-emitting copolymers bearing hole- or electron-transporter as well as bulky substituent have been successfully synthesized. Photophysical, thermal, electrochemical, and electroluminescent properties of these copolymers have studied and characterized. Bright and efficient blue fluorescence in the solid state have achieved by incorporating bulky substituent into the copolymer backbone. Both hole- and electron-transport-substituted copolymers apparently enhance the electroluminescent performance of their OLEDs. A better-balanced hole/electron charge carrier has ascribed to electron transporter-bearing copolymer OLED with a very mild luminous efficiency rolls off under a continuous operating voltages. For OPV application, two series of low-band-gap copolymers have been designed and synthesized, first for a comparison study of thiophene- or selenophene-bridged donor-acceptor copolymers. The replacement of thiophene with selenophene in the backbone of these copolymers has found a significant reduction of energy band gaps, principally due to the lowering energy level of LUMO than the raising energy level of HOMO in these copolymers. Density functional theory (DFT) calculations are performed on these copolymers to assist explaining the heteroatom substitution on the variation of HOMO/LUMO energy levels. Organic field-effect-transistors (OFETs) have also been fabricated to study the heteroatom effect on the hole mobility of these copolymers. Largely increased short-circuit current density (JSC) and slightly decreased open-circuit voltage (VOC) in OPVs using [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) as the electron acceptor have been demonstrated for selenophene-bridged donor-acceptor copolymers when compared with those of thiophene-bridged copolymers. Second, a series of donor-acceptor π-conjugated copolymers based on electron-rich benzo[1,2-b:4,5-b’]dithiophene (BDT) and electron-deficient cyanovinylene (CNV) or fumaronitrile (FN) moieties have been newly designed and synthesized. These copolymers are structurally tailored by anchoring alkyl chains on the backbone of the copolymer main chain to increase the solubility and molecular weights of copolymers. Having cyano- (CN) substituent on the copolymer chain, a considerable reduction of energy band-gap (Eg) has been found. It also deepens the HOMO energy level of copolymers, which increases VOC of OPVs. OFETs based on the CNV-containing copolymers and its composites with PC61BM have demonstrated hole mobilities close to those of non-annealed regioregular poly(3-hexylthiophene) (rrP3HT) and rrP3HT/PC61BM OFETs reported in literature, indicating similar charge transporting characteristics of the CNV-containing copolymer in fullerene-based OPVs. The CNV-containing copolymers are found solvent annealing effective in OPV fabrication for enhancing power conversion efficiency (PCE). This is rarely seen among BDT-based low band-gap donor-acceptor copolymers. High VOC (> 0.80 V) and PCE (~5.0 %) bulk-heterojunction [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM)-based OPVs have achieved by using the copolymers as the electron-donor material.
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Wright, Vincent Arthur. "Synthesis and characterization of new π-conjugated molecules and polymers containing phosphorus". Thesis, 2006. http://hdl.handle.net/2429/18224.
Повний текст джерелаАнотація:
In this thesis, the synthesis and characterization of a new class of π-conjugated polymers is reported. In these new macromolecules, poly(p-phenylenephosphaalkene)s, the main chain consists of alternating aromatic rings and P=C groups. Several model compounds (Ph-P=C(OSiMe₃)-Mes, Ph-P=C(OSiMe₃)-C₆Me₄-C(OSiMe₃)=P-Ph, Mes-C(OSiMe₃)=P-C₆H₄-P=C(OSiMe₃)-Mes) are reported for comparison to the polymer. This comparison illustrates that the polymer exhibits a degree of extended π-conjugation throughout the backbone of the material. The effects of using thiophene (Tp) as an aromatic spacer in a poly(p-thienylenephosphaalkene) are investigated, and reveal an increase in the UV/Vis maximum absorbance compared to phenylene systems. Two compounds (Tp-P=C(OSiMe₃)-Mes, Mes-C(OSiMe₃)=P-Tp-P=C(OSiMe₃)-Mes) are described as model compounds for the polymer. Mes-P=C(OSiMe₃)-Tp shows a significant increase in the UV/Vis maximum absorance wavelength compared to the conformational isomer discussed above. If the sterically demanding substituent resides on the phosphorus atom of the phosphaalkene bond in phenylene systems, a single isomer of the phosphaalkene forms selectively. Solid state structures of Mes-P=C(OSiMe₃)-Ph, Mes-P=C(OSiMe₃)-C₆H₄-C(OSiMe₃)=P-Mes, and Ph-C(OSiMe₃)=P-C₆Me₄-P=C(OSiMe₃)-Ph were determined. The corresponding polymer was synthesized and characterized. Due to the synthetic route to the P=C bond which forms a siloxy group, these compounds are quite sensitive to protonolysis. Preliminary results towards preparing more robust poly(p-phenylenephosphaalkene)s are discussed.Science, Faculty of
Chemistry, Department of
Graduate
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Samuel, Jibin J. "Ion insertion and Ion-host Interactions in Diketopyrrolopyrrole-based π-Conjugated Polymers". Thesis, 2022. https://etd.iisc.ac.in/handle/2005/5811.
Повний текст джерелаАнотація:
π-conjugated organic semiconductors are a class of technologically important materials with broad applicability in areas as diverse as energy conversion and storage, bioelectronics, and consumer electronics. This is because their properties can be tailored to suit a host of applications by, for example, subtle changes to their structure, conjugation length, side chains, crystallinity, and doping. Diketopyrrolopyrrole (DPP)-based π-conjugated polymers exhibit high ambipolar carrier mobilities and high performance in organic field effect transistors and organic photovoltaics.1 Owing to their low band gap, redox activity and favorable redox potentials, DPP-based π-conjugated polymers could also be suitable as channel materials for organic electrochemical transistors, electrodes for ion-insertion batteries, neuromorphic devices and sensing elements in bioelectronic applications. Electrochemical potential-dependent control of polymer redox coupled with ion-insertion, and the subsequent electrochemical doping-induced changes to the electronic conductivity of the semiconducting host, are central to the realization of these functional devices.
In this work, we used organic electrochemical transistors (OECTs) as a platform to simultaneously probe the mechanistic aspects of ion-insertion and electrochemical doping in DPP-based π-conjugated polymers.2 Based on OECT measurements, we discuss the role of ion-size, polymer side chains and electrolyte composition in dictating ion-insertion and transconductance of OECT devices. We corroborate these findings with spectroelectrochemical and electrochemical impedance measurements. Strikingly, our results show a polymer side-chain dependent asymmetry for the insertion of cations and anions. These cannot be fully understood when the electrochemical dopant is assumed to be in a polymer host matrix with a uniform dielectric constant. We discuss whether electrochemical dopant and host polymer interactions should be treated like ion-solvent interactions in classical electrolyte solutions.
Based on these mechanistic insights, we developed DPP-based OECTs that have balanced n- and p-type OECT device performance. We then configured arrays of single-component DPP-based OECTs into complementary like logic circuits to demonstrate NOT, 2-input NAND and 2-input NOR logic gates.3 Since the NAND and NOR circuits are configured from identical single-component OECTs, the NAND and NOR operations are fully voltage reconfigurable. Our work is a significant step towards building OECT-based bioelectronics and polymorphic circuits. Further, owing to their fast redox kinetics, we show that DPP-based polymers could be suitable as cathode materials in Li-ion batteries. We demonstrate fast and stable cycling of DPP-based cathodes in a Li-metal based half-cell with an average voltage of 2.2 V, 70% capacity retention at 500 C and high cycling stability of up to 1000 cycles.4
Our work is an important step towards a mechanistic understanding of ion-insertion and electrochemical doping in π-conjugated organic semiconductors. This understanding of mixed ionic and electronic conduction of these materials will be critical for a host of applications such as for example, i) interfacing circuits that mediate communication between an ionic biological circuitry and a fully electronic circuitry; ii) electrodes for energy storage devices; iii) electrochromic windows, iv) neuromorphic devices and v) polymorphic circuits with concealed logic operations.
References:
1. Catherine Kanimozhi, , Nir Yaacobi-Gross, Kang Wei Chou, Aram Amassian, Thomas D. Anthopoulos, and Satish Patil. “Diketopyrrolopyrrole–Diketopyrrolopyrrole-Based Conjugated Copolymer for High-Mobility Organic Field-Effect Transistors.” Journal of the American Chemical Society 134, no. 40 (2012): 16532–35.
2. Jonathan Rivnay, Sahika Inal, Alberto Salleo, Róisín M. Owens, Magnus Berggren, and George G. Malliaras. “Organic Electrochemical Transistors.” Nature Reviews Materials 3, no. 2 (2018): 17086.
3. Jibin J. Samuel, Ashutosh Garudapalli, Aiswarya Abhisek Mohapatra, Chandrasekhar Gangadharappa, Satish Patil, and Naga Phani B. Aetukuri. “Single-Component CMOS-Like Logic Using Diketopyrrolopyrrole-Based Ambipolar Organic Electrochemical Transistors.” Advanced Functional Materials 31, no. 45 (2021): 2102903.
4. Jibin J. Samuel, Varun Kumar Karrothu, Ram Kumar Canjeevaram Balasubramanyam, Aiswarya Abhisek Mohapatra, Chandrasekhar Gangadharappa, Varun Ravi Kankanallu, Satish Patil, and Naga Phani B. Aetukuri. “Ionic Charge Storage in Diketopyrrolopyrrole-Based Redox-Active Conjugated Polymers.” The Journal of Physical Chemistry C 125, no. 8 (2021): 4449–57.
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Shahid, Munazza [Verfasser]. "Novel thieno[3,4-b]pyrazine based π-conjugated [pi-conjugated] polymers for optoelectronic devices / von Munazza Shahid". 2006. http://d-nb.info/989311139/34.
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Lin, Tzu-Wei, та 林祖薇. "Synthesis and Characterization of Low Band-Gap π-Conjugated Polymers Containing D-π-A Structure for Organic Photovoltaics". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/jskeb6.
Повний текст джерелаАнотація:
碩士國立臺灣科技大學
化學工程系
103
In this work, we have synthesized thirteen different π-conjugated donor-acceptor (D-A) copolymers (C6C10DPP-H4, C4C8DPP-H4T, C2C6DPP-H4T, C16DPP-H4T, C12DPP-H4T, C8DPP-H4T, BT-H4T, BT2F-H4T, BT2CN-H4T, BS-H4T, BS2F-H4T, BS2CN-H4T and BTDI-H4T) bearing regioregular 3,4',4'',4'''-tetrahexyl-2,2':5',2'':5'',2'''-quaterthiophene (H4T) as the electron donor with various electron acceptors via Stillie coupling reaction.
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Laquai, Frédéric [Verfasser]. "Electronic energy transfer processes and charge carrier transport in π-conjugated [pi-conjugated] polymers / vorgelegt von Frédéric Laquai". 2006. http://d-nb.info/980153913/34.
Повний текст джерела
39
Lin, Yen-Ting, та 林彥廷. "The Self-Assembly of Bio-inspired π-Conjugated Polymers and Their Applications for Organic Electronics". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/2wv548.
Повний текст джерелаАнотація:
博士國立交通大學
材料科學與工程學系奈米科技碩博士班
105
The selfassembly of bioinspired conjugated polymer in solution and in solid state has attracted intense attentions; they are promising candidates with a variety of potential applications for nanostructural materials. Typically, synthetic macromolecules differ with respect to their biological counterparts, for example of nucleic acid, where the selfassemblies usually involved direct hydrogen bonding and stacking interaction. Bioinspired conjugated polymer displays interesting selfassembly phenomenon that allows the creation of hybrid materials for organic electronic devices especially for the generation of upcoming flexible application. In this dissertation, we focus on employing the concept of supramolecular to manipulate morphology of existed πconjugated polymers by noncovalent interaction. A new adeninegrafted poly(3hexylthiophene) (PAT) polymer has been prepared and investigated, which exhibits high thermal stability, good solvent resistance, excellent optical and electrochemical properties in the solution state and solid state owing to the adenine induced physical crosslinking. (1) We develop a new concept to construct and enhance the properties of existing functional polymers through biocomplementary interaction has been exploited. The new DNA-mimeticπconjugated poly(3hexylthiophene) (P3HT) has been synthesized as adenine-grafted poly(3adeninehexyl thiophene) (PAT) followed by blending with [6,6]phenylC61butyric acid methyl ester (PC61BM) as a new bulky heterojunction (BHJ) structure material. We use diverse polarity solvents in this blending system (PAT/PC61BM) and surprisingly found the formation of polymeric micelles in dimethyl sulfoxide (DMSO) solvent, and reversed hybrid micelles in trichloroethylene (TCE) solvent based on dynamic light scattering (DLS), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscope (AFM) analyses. By using cyclic voltammetry (CV), we found that the lowest unoccupied molecular orbital (LUMO) of PAT is higher than commercial P3HT and that it enlarges the energy gaps between the LUMOs of the donor-acceptor pair; hence, PAT has a better ability to prevent the electrons from flowing back. The reversed hybrid system shows a greater conductivity with Voc= 0.54 V, Isc= 229 pA and 5-fold enhanced performance compared to the initial PC61BM. The polymeric micelle system is successfully employed in a fully polymerbased memory device. (2) In this section, we report the first observation, through Xray diffraction, of noncovalent uracil–uracil (U–U) dimericπstacking interactions in carbon nanotube (CNT)–based supramolecular assemblies. The directionally oriented morphology determined using atomic force microscopy revealed highly organized behavior through πstacking of U moieties in a Ufunctionalized CNT derivative (CNTU). We developed a dispersion system to investigate the bio-inspired interactions between an adenine (A)terminated poly(3adeninehexyl thiophene) (PAT) and CNTU. These hybrid CNTU/PAT materials interacted through stacking and multiple hydrogen bonding between the U moieties of CNTU and the A moieties of PAT. Most importantly, the U•••A multiple hydrogen bonding interactions between CNTU and PAT enhanced the dispersion of CNTU in a high-polarity solvent (DMSO). The morphology of these hybrids, determined using transmission electron microscopy, featured grapelike PAT bundles wrapped around the CNTU surface; this tight connection was responsible for the enhanced dispersion of CNTU in DMSO. (3) In the final section, we have developed a strategy for modifying the channel layer of organic thin film transistors (OTFTs) through side-chain induced selforganization into a well-ordered film. To obtain selectively self-patterned layers, we treated an adenine-functionalized poly(3hexylthiophene) (PAT) with adenosine triphosphate (ATP). Using this strategy, interchain charge transport resulting from πconjugation was selected to control the polymer morphology, without the need of additional chemical synthetic processing. The side chain–induced self-organization can be understood in terms of supramolecular interactions. The πelectrons were delocalized among the thiophene rings, thereby improving the interchain charge transport ability; the resulting planar πelectron system in PAT:ATP resulted in closer intermolecular ππ distances, facilitating enhanced charge carrier mobility within a fibrillar structure. The PAT:ATPbased OTFT device exhibited moderate to improved electronic characteristics, with an average field mobility of 1.6 10–4 cm2 V–1 s–1 at –30 V and a threshold voltage (Vth) of 5 V, and an on/off current ratio of 106. This method has great potential for inducing selective intermolecular interactions in fully solution processed electronic devices.
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Hildner, Richard [Verfasser]. "Investigation of the photophysical properties of π-conjugated [pi-conjugated] polymers : a study by non-linear, time-resolved, and single-molecule spectroscopy / eingereicht von Richard Hildner". 2008. http://d-nb.info/989269140/34.
Повний текст джерела
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Chang, Yao-Tang, та 張耀唐. "High Triplet Energy Silylene-Diphenylene σ-π Conjugated Polymers for Highly Efficient Electrophosphorescence and Device Structure Design for Voltage Independent White Light Emission". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/68jts9.
Повний текст джерелаАнотація:
博士國立清華大學
化學工程學系
101
Abstract Compared to the high brightness and high efficiency of inorganic LED, late developing organic LED (OLED) is difficult to compete with it. However, in solid-state lighting industry, the point lighting source of the former cannot be applied to large area, and requires utilizing a diffuser to improve the problem of harsh in one point and uneven in full plane. On the other hand, OLED possesses natural plane lighting, and is no need to be fabricated by complicated epitaxy process like inorganic LEDs. Because of flexibility of organic molecules, it can be fabricated on flexible substrates and provides suitability for carrying. Furthermore, the use of vacuum deposition for depositing various layers allows flexibility in device structure design for exciton and charge blocking layers to enhance device performance. Normally, an efficient OLED device contains more than five layers. However, the device with large number of layers could lead to lower production yields and is able to be slow fabrication speed. On the contrary, due to the advantages of wet process, PLED is able to be fabricated at higher speed and thus at lower costs. The most important characteristic of PLED is that permits an integration of various functional groups like charge transport moieties and/or emitting species into one polymer chain for simplifying the fabrication process. In the meantime, it not only simplifies the device structure but also excludes possibility of phase separation host-guest systems. Nowadays, for OLED system, some research groups have attempted to fabricate device using wet process. However, as compared to vacuum deposition process, the efficiency was dropped by 36% resulting from poor film quality. The current state of art for green emission efficiency is in the level of 20-22% in external quantum efficiency (EQE); while green emission of PLED with conjugated polymers is in the level 11%, only half of the above level. The use of non-conjugated polymer (polyvinyl carbazole, PVK) as host with green phosphor as dopant and large amount (about 30%) of electron transport material (PBD) to assist charge balance able to reach EQE at the level of 16-18%. However it suffers from rapid phase separation observable within hours or even minutes and is not suitable for practical use. So far, the most challenging problem in PLED is inadequate efficiency, which is in needs of being promoted immediately. In this thesis, the contents are divided into three parts giving in chapters 4, 5 and 6. In the first part, we design a highly efficient and voltage independent white light device. In the second part, we design a new series of polymers by introducing hole transport moiety (TPA) and electron transport moiety (OXD) as side arms on the silicone of silylene-diphenylene backbone to enhance its charge transport abilities. Since each unit in the polymer has triplet energy higher than 2.9 eV, we may expect that the polymer has triplet energy of 2.9 eV and is suitable to act as hosts for phosphor dopant. In the third part, we center on the physical properties and device performance affected by end groups at side arms of the transport moieties. In chapter 4, we utilize our developed material, PFCn6, as an interlayer and introduce β-PFO for blue emission layer and PFO: rubrene for yellow emission layer to obtain stable white light with fully wet process. Due to the whole device host materials are consisted of PFO main chain structure, there are no energy barriers between each layer. Based on the hole mobility of β-PFO, the electron mobility of PFO from literatures and both mobilities of PFCn6 determined using SCLC measurement, we calculate the ratio of travel time (R) for hole to pass through β-PFO and PFCn6 layers to that for electron to pass through PFO: rubrene and PFCn6; for the device R60/20 (60 nm β-PFO and 20 nm PFO: rubrene layers) and R40/40, they are 1.09 and 0.58, respectively. These results show that the times for holes and electrons traveling before recombination in the devices with 60/20 nm (blue/yellow layers) are more balanced than that with 40/40 nm system. Thus, whatever the external electric field varies, the electroluminescences are almost the same, and the maximum brightness of 15695 cd/m2, the maximum luminance efficiency of 5.43 cd/A are achieved. Besides, the CIE coordinates of (0.32, 0.36) are very close to the standard white light of (0.33, 0.33). In chapter 5, we introduce the phosphor Ir(ppy)2(acac) as green dopant to the proposed bipolar polymers with silylene-diphenylene as backbone, Si(OXD)(TPA), because its HOMO/LUMO levels are 5.2/2.5 eV just lying in between HOMO of TPA (5.3 eV) and LUMO of OXD (2.4 eV). From the photoluminescence (PL) measurement, although the bipolar polymers contain exciplex emission, the films only emit green light after doped 8 wt% Ir(ppy)2(acac), indicating that the exciplex can effectively transfer its energy to green emitter without significant loss. By introducing Cl-ITO as anode (allowing an elimination of PEDOT:PSS layer which is usually used as HTL) and adjusting the thicknesses of ETL and EML, we achieve the high device performance 80.1 cd/A (EQE 21.2%) of Si(tOXD)(oTPA) and 73.5 cd/A (EQE 19.5%) of Si(tOXD)(tTPA), which are extremely high compared to the current reported value of PLED 11% in EQE. This molecular design strategy opens a broad avenue leading toward industrialization of PLED for its two-layer-only device and high performance. In chapter 6, we focus on the effects of using tert-butyl instead of hexyloxy at the side arms of transport moieties, and we found that even the steric hindrance by the tert-butyl group does not affect much on the charge transport. From single carrier examination, the electron current density is 2-3 magnitude higher than hole current density in the bipolar materials. Therefore, we introduce a PVK layer as HTL/EBL, replace CsF by Ca to reduce electron current, and use high conductivity PEDOT:PSS, the resulting device reaches the efficiency 41.6 cd/A in green emission.
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Wu, Jhao-Lin, та 吳昭霖. "Study of low band-gap π-conjugated polymers for organic photovoltaics and perylene diimide derivatives as electron transporting materials for perovskite solar cells". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/283g3b.
Повний текст джерелаАнотація:
博士國立臺灣大學
化學研究所
106
This thesis can be divided into 2 parts. The first was concentrated on designing and synthesizing donor materials for the organic photovoltaics (OPVs). The second part was focused on developing of electron transporting materials for the perovskite solar cells (PVSCs). In the first part, we have synthesized and characterized a series of diketopyrrolopyrrole (DPP)-oligothiophene copolymers, of which the number of regioregular oligothiophene ring (2T, 3T and 4T) and the arrangement of the alkyl side-chain on regioirregular quarterthiophene (4T0, 4T1 and 4T2) are variable. The side chains with regioregular lead to more planar copolymer backbones and higher short circuit current (JSC), but backbone torsion (due to regioirregular side chains) generates greater open-circuit voltages (VOC) for DPP-oligothiophene copolymers. The increasing thiophene ring progressively raises HOMO energy level of copolymers but marginally affects their band gaps. Additionally, the HOMO energy level was found declined significantly with side-chain regioirregularity, because of reducing length of π-conjugation. The HDDPP4T0 exhibits the strongest absorption, extensive network structure, and high hole mobility (µh = 6.04 × 10-4 cm2 V-1 s-1). These characteristics contribute to the exceptional high JSC of 18.96 mA cm-2 for OPV with PCE = 6.12%. However, the HDDPP4T1 having an optimal combination of π-conjugation and energy level affords the second highest VOC (0.73 V) and the third highest JSC (16.89 mA cm-2), resulting the best PCE of 7.51 % among all. X-ray scattering, transmission electron microscopy, atomic force microscopy, and space-charge-limited-current (SCLC) easurements reveal that the solvent additive of diphenylether (DPE) enables PC71BM-blended copolymers thin film in crystallinic fibril with enhanced hole mobility. In the second part, we have developed and demonstrated three solution processable perylene diimides, i.e., X-PDI, X = H, F, or Br, as nonfullerene electron accepting and electron transporting materials in inverted PVSCs. Whereas H-PDI or F-PDI performs unsatisfactorily, our best PVSC is based on Br-PDI exhibiting PCE of 3.23%, which is just a bit shy of 4.13% of fullerene (PC61BM) PVSCs. Through a series of physical, spectroscopic, and microscopic studies, we have understood that the low solubility of F-PDI is a major factor causing the poor quality of the thin film, rendering virtually no photovoltaic effect for F-PDI. Although the solubility of H-PDI is better than F-PDI, the inferior electron mobility and conductivity make H-PDI PVSCs have relatively worse performance. Having the highest solubility, electron mobility, and conductivity among X-PDI, Br-PDI based PVSCs are almost as efficient as PC61BM based PVSCs. Within the ZnO NP as a CBL in the PVSCs, the PCEs of PVSCs based on X-PDI or PC61BM are significantly improved to 7.78%, 10.50%, and 11.07%, respectively.We infer that the CBL of ZnO NP has the function of interspacelling on the defect of X-PDI or PC61BM thin film, reducing the direct contact of Ag cathode to the perovskite material. Due to the strong molecular interaction, F-PDI aggregates significantly in thin film, creating too many and too large defects to be remedied or improved with or without CBL of ZnO NP. Very poor electron mobility and conductivity of F-PDI are two other factors devastating its PVSCs. Through this study, we have demonstrated that the simple mono-bromine substituted perylene diimide (Br-PDI), is solution processable and has potential for use as a non-fullerene electron accepting and electron transporting material in inverted PVSCs.
43
SUN, WEI-YEN, та 孫唯晏. "Development of Novel Self-Assembled π–Conjugated Polymer Material Systems". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/23u7hr.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
分子科學與工程系有機高分子碩士班
107
In this thesis, a π-conjugated polymer poly(3-butylthiophene) (P3BT) with metal ion-chelating ability was used to develop novel organic/inorganic hybrid materials. For the fabrication of the hybrid system, P3BT/Zn2+ complexes were first prepared by dissolving zinc acetate dihydrate in a P3BT/toluene solution and then a marginal solvent anisole was added into the solution to induce the crystallization of the complexes to form P3BT/Zn2+ nanowires dispersed in the solution system. Subsequently, thin film samples of P3BT/ZnO were further prepared by drop casting the P3BT/Zn2+ on flat substrates, followed by healing the dried films at 220℃ for 30 min under air condition. During the thermal treatment process, Zn2+ could be converted to ZnO through an oxidation reaction, resulting in P3BT/ZnO hybrid materials. After the successful fabrication, the nanomorphologies and crystalline structures of the P3BT/ZnO hybrid samples were investigated by using TEM and GIWAXS measurements, respectively. From the experimental results, we could observe that ZnO nanocrystals selectively located along the highly crystalline P3BT nanofibrils, indicating that the P3BT nanowires served as an efficient structural directing template to coassemble inorganic materials into the polymeric hosts. The photophysical properties of the P3BT/ZnO hybrid system were further studied by using UV-Vis absorption and photoluminescence measurements. It should be noted that a significant photoluminescence quenching effect could be observed. The occurrence of this photoluminescence feature could be attributed to the nanowire structured P3BT/ZnO hybrid system which possessed large donor/acceptor interfaces for efficient exciton dissociation and provided continuous nanochannels for the following charge transport. Besides the hybrid systems using conventional P3AT with alkyl side chains, we further developed a cross-linkable thiophene based π-conjugated polymer poly-3-(6-bromohexyl)thiophene (PBHT) by incorporating a bromide group on the alkyl side chain. The molecular packing, thermal properties, optoelectronic characteristics and crosslinking features of this polymer were studied and compared with those of traditional P3ATs. Furthermore, we used the 3-(6-bromohexyl)thiophene and 3HT monomers to developed a π-conjugated poly(3-hexylthiophene)-poly-3-(6-bromohexyl)thiophene random copolymer system and studied the properties of this new type of polymeric material. We believe that the novel material systems developed in our study shows potential for use in advanced optoelectronic applications.
44
蔡武諺. "Synthesis and optoelectronic property of novel conjugated D-π-A polymer". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/30650292922342483529.
Повний текст джерелаАнотація:
碩士逢甲大學
化學工程學系
104
Conjugated polymers play an important role in modern technology due to their numerous potential applications including organic light-emitting diode, solar cell, conducting material and bio-imaging. In this work, a series of novel conjugated copolymers consist of electron donor and electron acceptor are designed and synthesized. The optical properties, thermal stability, electrochemical and conductivity of copolymers were investigated. The electron transfer phenomenon was observed in which those copolymers displayed significant solvent-dependent property. Moreover, those copolymers displays exhibited have high quantum yield. On the other hand, the TGA analysis showed those copolymer have high thermal stability. The HOMO (Highest occupied molecular orbital) and LUMO (Lowest unoccupied molecular orbital) energy levels of copolymers were determined by electrochemical method. These results would be helpful when those copolymers were used in optoelectronic application. The disadvantage of these copolymers was the conductivity was low, and it might limit the performance of these material.
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Yu, Da-Cyuan, та 余大全. "Integrating π-Electron of Chromophore and Conjugated Polymer – Main Chain System Study". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/22388287181482954349.
Повний текст джерелаАнотація:
碩士國立清華大學
化學工程學系
94
Conjugated polymers used in NLO are investigated in this study. Poly(n-vinyl-carbazole) (PVK) and polycarbazole (PCZ) have been used as a host polymer. Two chromophores, 9-Hexyl-3,6-bis-[2-(4- nitro-phenyl)-vinyl]-9H-carbazole (CzPhNO2) and 2- {2,6- Bis- [2- (4- diethylamino-phenyl)-vinyl]-pyran-4-ylidene}-malononitrile (DCDEt), have been prepared and used in four guest/host NLO systems. The d33 value has been improved when PCZ was added. The anchoring effect of CzPhNO2 leads better thermal stability than DCDEt, meanwhile, the plasticizer effect of PCZ leads lower effective transition temperature (T0). UV-Vis spectra show apparent red-shift in each system after casting. Accordingly, π-aggregation may be one of the reasons which improve d33 of the material. Besides, three conjugated polymers have been synthesized successfully as main-chain NLO materials by self-polymerization and Suzuki coupling. The Td/Tg of the three polymers are 276℃/125.6℃(Poly(2-(2,6- distyryl-pyran-4-ylidene)-malononitrile)—P1), 329.5℃/118.2℃(Poly{2-[2-(2-Biphenyl-4-yl-vinyl)-6-styryl-pyran-4-ylidene]- malononitrile}—P2), and 301.7℃/149.1℃(Poly{(9,9-dihelxyl- 9H-fluorene-2,7-yldene)-alt—(2-{2,6-bis[2-(2-hexyloxyl-5-phenylene)vinyl]-pyran-4-ylidene}-malononitrile)} —P3). P1 performs the best SH intensity of 11.5 pm/V between the three polymers while p3 performs the best Tg. The temporal stability was investigated by tracing the SH coefficient as a function of temperature. The effective transition temperature of P1, P2, and P3 are 100.4℃, 86.4℃, and 81.3℃.
46
Godana, Alis, та Alis Godana. "Morphology and Photophysical Properties of Conjugated Polymer Nanoparticles Based on Rapid Precipitation and Self-Assembled π-Conjugated Systems". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/632c4v.
Повний текст джерелаАнотація:
博士國立臺灣科技大學
材料科學與工程系
107
The design and synthesis of novel -conjugated materials is still an attractive research field due to their interesting optoelectronic properties, which make them potential candidates in various applications such as light emitting devices, solar cells and sensors. We have prepared conjugated polymer nanoparticles using rapid precipitation and self-assembled method. Self-assembly refers to the process by which nanoparticles or other discrete components spontaneously organize due to direct specific interactions, or indirectly, through their environment. Rapid precipitation was prepared by rapid injection of conjugated polymer (good solvent) solution into poor solvent under sonication. This dissertation is organized based on two independent sections. In the first section, novel conjugated polymers containing fluorenes, PEGylated carbazoles and diphenylamines were synthesized by the palladium catalyzed Suzuki-Miyaura cross-coupling reaction. The dimensions of the conjugated polymer nanoparticles were in a range of 35–65 nm as observed by SEM analysis. A blue-shifted absorption of the conjugated polymer nanoparticles containing fluorenes and diphenyl amines or 2,7-linked carbazoles was observed compared to that of the polymer solution, this can be attributed to aggregation-induced disorder. The emission of the polymer nanoparticles containing fluorenes and carbazoles is red-shifted and this can be attributed to the increase in interchain interactions possibly due to conjugated polymer chains collapsing in water during nanoparticle formation. For all polymers, the decreases in emission quantum yields on going from polymer solution to nanoparticle dispersion were reflected the aggregation of the polymer chains in aqueous media. In the second section, we synthesized conjugated copolymers containing fluorene and diphenylamine moieties containing octyl and triethylene glycol side chains via Suzuki-Miyaura cross-coupling reaction and their structures have been characterized. Conjugated polymer nanoparticles and self-organization of the polymers have been prepared by rapid precipitation and solvent diffusion methods, respectively. The morphologies of the conjugated polymers exhibited well-defined spherical amorphous structures and crystalline microspheres with the diameter ranging from several nanometer to micrometer. Self-assembled conjugated polymer aggregates were obtained in a selective good solvent/ poor solvent mixture. The emission maximum of the dispersed polymers in water was significantly red-shifted with dramatically reducing the photoluminescence quantum yield in comparison with those polymers in good solvents. In addition, the emission maximum of the self-assembled copolymers was barely red shifted with slightly decreasing the photoluminescence quantum yield.
47
Chen, Jhih Yuan, та 陳知遠. "The Influence of Single-crystalline Gold Plate Substrate on the Whispering-Gallery Modes of Semiconducting Fluorescent π-Conjugated Polymer Microspheres". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/ahh948.
Повний текст джерелаАнотація:
碩士國立清華大學
化學系
105
Light can be totally internally reflected inside a sphere made of dielectric material with refractive index higher than the environment. At specific wavelengths, standing waves are established, forming the photonic whispering-gallery modes (WGMs). On the interface of air and gold, surface plasmons (SPs) can be excited by photons if the momentum matching condition is fulfilled. When the spherical WGM resonator is placed on the gold substrate, the evanescent near fields of the WGMs can interact with the gold substrate. Depending on the polarization and the orbiting orientation of the WGMs, the interaction can result in spectral shift and intensity variation. The influence of the gold substrate on the WGM is of fundamental interest and practical importance when the sphere is to be connected to metallic electrodes for photoelectric effects. In this thesis, we investigate the influence of single-crystalline gold substrate on the WGMs of self-assembled semiconducting fluorescent π-conjugated polymer microspheres. In particular, we focus on the effects on WGM peak intensity and spectral shift. For peak intensity, we found that all peaks and the broadband fluorescence background in the emission spectrum are enhanced by the gold substrate. However, the intensity of transverse magnetic (TM) WGMs is usually lower than the corresponding transverse electric (TE) modes. This is found to stem from the WGM-to-SP coupling of the TM modes via Otto configuration. As for the spectral shift, we have observed that gold substrate results in blue shift of TE modes and red shift of TM modes. While for ITO substrate, both TE and TM show red shift. With theoretical and numerical analysis, we attribute the red and blue shift of the TM and TE mode to the negative and positive Goos-Hänchen shift on the gold substrate, respectively. The negative and positive Goos-Hänchen shifts correspond to effective enlargement and shrinkage of the sphere circumference and thus the red-shifted and blue-shifted peak positions, respectively. Typically, the assignment of TE and TM modes relies on theoretical analysis. This study shows that by identifying the metal surface plasmon coupling effect and the Goos-Hänchen shifts, the assignment of TE and TM mode can also be done experimentally. Finally, the influence of the graphene substrate on the whispering gallery mode is discussed. Graphene is known to be an efficient quencher and the quenching effect depends on the dipole orientation with respect to the graphene surface. Dipoles parallel to the graphene plane are quenched much more effectively than those perpendicular to the surface. Therefore, it is interesting to know if graphene substrate has different quenching effects on the TE and TM modes. The preliminary results show that there is no observable difference. This might be due to the fact that the coupling of WGMs to graphene substrate is different from that of dipole sources to graphene. The details of the influence of graphene on WGMs require further experimental and theoretical works.