Dissertations / Theses: 'Polymer luminescence'

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Dailey, Stuart. "A study of conjugated polymers and their applications in light-emitting diodes." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4744/.

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The initiation of research into conjugated polymer electroluminescent devices in Durham is reported. The apparatus required for the fabrication and characterisation of polymer light-emitting diodes (LEDs) is outlined, and the essential assumptions and calculations required to determine their efficiency, brightness and colour are summarised. Optical and electrical characterisation of a range of polymers is reported, including polypyridine (PPY) and a range derivatives, poly(p-phenylene vinylene) (PPV) and poly(2-methoxy, 5-(2'ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV). The optical properties of PPY in solution, film and dilute solid state are characterised. The conjugation length of PPY is investigated by deliberate disruption of the conjugation by the inclusion meta-links in the otherwise para-linked polymer. The effect of altering the chemical structure of PPY is investigated by the study of some PPY derivatives including random and regular copolymers. The consequences of using precursor polymers, especially the effects of conversion on indium tin oxide coated substrates are investigated using absorption and luminescence spectroscopy and capacitance-voltage analysis. Electroluminescence from a number of conjugated polymers is reported and the efficiency, spectral output and device characteristics are presented. The formation of Schottky barriers in some polymer devices is investigated using quasi-static capacitance-voltage measurements. Improvements in the quantum and power efficiency of polymer LEDs have been achieved using two hole-transporting polymers, poly(vinyl carbazole) and the doped, conducting form of polyaniline. A substantial improvement in quantum efficiency has also been demonstrated when PPY is used as an electron-transporting layer in PPV and MEH-PPV based light-emitting diodes. The variation in quantum efficiency and emission spectrum with the ratio of the thickness of the two polymer layers is reported and analysed.

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Thomas, Janet Lyn. "The effect of dyeing parameters on the lightfastness properties of acid dyes in nylon 6,6 fibres." Thesis, Manchester Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296491.

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Kage, Daniel. "Studies on fluorophore-loaded polymer microbeads and luminescence lifetime encoding in flow cytometry." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20608.

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Die Dissertation umfasst zwei Themenblöcke: Zum einen wurden die optisch-spektroskopischen Eigenschaften von fluoreszenten, farbstoffbeladenen Polymer-Mikropartikeln untersucht. Zum anderen wurde die Anwendbarkeit solcher Partikel für die Lumineszenzlebensdauer-Kodierung in der Durchflusszytometrie evaluiert. Die Charakterisierung der farbstoffbeladenen Mikropartikel erfolgte mittels optischer Spektroskopie. Am Beispiel mit Rhodamin 6G beladener Polymethylmethacrylat-Partikel konnte ein besseres Verständnis des Einbaus der Farbstoffmoleküle und der resultierenden Fluoreszenz-Charakteristika gewonnen werden. Es stellte sich heraus, dass die Beladungseffizienz stark vom mittleren Partikeldurchmesser und den Synthesebedingungen abhängt. In Verbindung mit den beobachteten optisch-spektroskopischen Eigenschaften wurde geschlussfolgert, dass sich eine farbstoffreiche Schicht an der Oberfläche der Partikel bildet, die sich wesentlich von den sterisch eingebauten Farbstoffmoleküle im Partikelvolumen unterscheidet. Hohe Farbstoffkonzentrationen in dieser Oberflächenschicht führen vermutlich zu Aggregation. Des Weiteren deuten Veränderungen der Fluoreszenzeigenschaften auf intrapartikuläre Energiewanderung bei zunehmender Farbstoffkonzentration hin. Diese Interpretation der experimentellen Ergebnisse konnte qualitativ durch einen Algorithmus zur Simulation der Energiewanderung bestätigt werden. Die Anwendbarkeit der Lumineszenzlebensdauer als Kodierungsparameter in der Zeitdomäne konnte unter Verwendung eines Durchflusszytometer-Prototypen analysiert werden. Die wohl größte Herausforderung bei der Lebensdauermessung in der Durchflusszytometrie ist die kurze Interaktionszeit zwischen Objekt und Anregungslicht. Synthetische Daten wurden herangezogen, um den Einfluss einzelner Messparameter und -bedingungen unabhängig voneinander abzuschätzen. Es konnte festgestellt werden, dass die Lumineszenzlebensdauer als Kodierungsparameter in der Zeitdomäne prinzipiell zugänglich ist. This thesis comprises two main topics. First, the optical-spectroscopic properties of fluorescent microbeads loaded with organic dyes were studied. In the second part, the feasibility of time-domain luminescence lifetime encoding in flow cytometry based on such microbeads was assessed. The study of the dye-loaded polymer microbeads was based on optical spectroscopy. Poly(methyl methacrylate) beads loaded with rhodamine 6G were used as an example system to achieve a better understanding of the dye incorporation procedure. The dye loading efficiency turned out to be strongly dependent on the mean diameter of the beads and on the amounts of certain compounds used for the bead synthesis. In correlation with the observed fluorescence characteristics, it was deduced that a layer with high local dye concentration forms around each bead. The properties of this layer substantially differ from those of the sterically incorporated dye molecules in the bead core. The high dye concentration in this layer results in aggregation accompanied by the respective changes of the fluorescence characteristics of the beads. Moreover, the observed changes in fluorescence properties indicated the existence of an intra-particulate energy migration process at increased dye loading concentrations. A simulation of the energy migration process based on a random walk algorithm confirmed the interpretation of the experimental results. For the assessment of luminescence lifetime encoding in time-domain flow cytometry, a prototype setup was used. The main issue of lifetime determination in flow cytometry is represented by the short interaction time of only tens of microseconds of the objects with the excitation light spot. Synthetic data were used to study certain measurement parameters and conditions as well as the data analysis procedure independently of other influences. As a result, luminescence lifetime is generally applicable as an encoding parameter in time-domain flow cytometry.

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Thomas, Tudor Huw. "Enhancing fluorescence and charge transport in disordered organic semiconductors." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/283199.

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High performance optoelectronic applications require simultaneously high mobility ($\mu$) and high quantum efficiency of fluorescence ($\Phi$). While this has been realised for organic small molecule semiconductors, applications such as high efficiency organic photovoltaics and bright organic light-emitting diodes towards electrically driven lasing are hampered by an apparent trade-off between $\mu$ and $\Phi$ in disordered systems. Recent reports of state-of-the-art device performance often optimise $\mu$ and $\Phi$ in disordered organic materials separately, and employ multi-layer architectures. In this work, we investigate materials in a class of donor-acceptor polymer materials; the indacenodithiophene-$\textit{alt}$-benzothiadiazole family, which demonstrate high $\mu$ in spite of a low long-range structural order, to understand the interplay between these two important device figures-of-merit. In the first section, we evaluate the effect of various tuneable parameters on $\mu$ and device performance in organic field-effect transistors. Using chemical modifications to the solubilising side chains, we observe that the substitution of bulky groups leads to a reduction of the hole mobility $\mu_h$ > 2 cm$^{2}$/Vs to ~ 0.5 cm$^{2}$/Vs in the benchmark polymer of this family, indacenodithiophene-$\textit{alt}$-benzothiadiazole. Crystallographic and exciton-quenching based experiments confirm this observation is closely related to the degree of polymer backbone aggregation, and this leads to a different temperature evolution of the transport behaviour. In order to reliably improve $\mu$ in these systems, an elongation of the donor subunit is required. This increases the $\pi$-electron density on the donor, and can lead to an improvement in $\mu$ where the side chain density is decreasing. This chemical design, leading to a more highly aggregated structural motif is much more potent in determining $\mu$, it seems, than design strategies to further improve the energetic disorder in the joint density of states and the potential barrier to torsion, which may be near optimised in these low-disorder systems. In the second section, we unpick the precise relationship between the degree of aggregation apparently linking high $\mu$ to low $\Phi$. With a prototype system, we compare the photophysics of two indacenodithiophene-$\textit{alt}$-benzothiadiazole polymers differing by side chain bulkiness. Despite the aforementioned suppression of $\mu$, we observe an improvement to $\Phi$ of $< 0.02$ to $\sim 0.18$ upon backbone separation. This derivative has the highest $\Phi$ reported for any polymer with $\mu$ exceeding that of amorphous-Si. However, the $\Phi$ in the more aggregated derivative is not limited by the formation of non-emissive excitons, but rather by an additional internal conversion pathway which is strongly temperature dependent, and mediated by Raman-active vibrations and close chain coupling. Extending this study, we analyse additional materials in this family with the highest $\Phi \cdot \mu$ values reported for conjugated polymers. We find that increasing the energy gap leads to an increase in $\Phi$, and secondary emission pathways via weakly luminescent inter-chain charge transfer species. By solving the rate equations for exciton recombination, we use the radiative rate of inter-chain luminescence as a probe to show strong wavefunction mixing at close-contact points for some polymers, and suggest this as the origin for a superior $\mu$ in dithiopheneindenofluorene-$\textit{alt}$-benzothiadiazole compared to indacenodithiophene-$\textit{alt}$-benzothiadiazole. We demonstrate how low $\mu$ can be decoupled from the energy gap ($E_g$), and propose backbone elongation leading to increased inter-chain wavefunction overlap and a higher $E_g$ as a design rule to increase $\Phi$ and $\mu$ together. Finally, we assess the role of low-frequency vibrations in organic semiconductors displaying thermally activated delayed fluorescence (TADF). In the low-aggregation limit where $\Phi$ is maximised, we show that non-radiative triplet recombination is strongly related to low frequency torsional motion, and both are reduced in the presence of a rigid polymer host matrix for various TADF materials across different classes. However, we also explore the importance of rotational freedom in determining the oscillator strength, exchange energy, and spin-orbit coupling matrix elements which mediate luminescence in the absence of a rigid host. We demonstrate that suppressing dynamic motion is a powerful tool to modulate the photophysical properties of these emitters, and can lead to improved $\Phi$ particularly for low $E_g$ emitters.

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Aliprandi, Alessandro. "Platinum complexes and their luminescent assemblies." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF041/document.

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Cette thèse porte sur la synthèse et la caractérisation photophysique d'une série de composés neutres luminescents de platine (II) contenant un ligand tridentate dianionique chromophore N-donneur et un ligand auxiliaire monodentate. Les composés montrent un changement notable des propriétés de photoluminescence selon l'auto-assemblage en raison de la formation d'interactions intermoléculaires non covalentes faibles telles que metal-metal et π-π. Nous avons démontré comment les complexes de Pt (II) peuvent être auto-assemblés d'une manière contrôlée et précise en jouant sur les facteurs cinétiques et thermodynamiques, ainsi que la morphologie des différents ensembles étudiés. Ces approches ont conduit à des matériaux avec des propriétés améliorées et uniques tels que le mécano-chromisme, ainsi que l'absorption et l'émission de la lumière polarisée. Les composés étudiés et leurs assemblages sont utiles non seulement pour le développement de nouveaux matériaux fonctionnels supramoléculaires en équilibre et hors- équilibre, mais aussi pour des applications en bio-imagerie This thesis focuses on the synthesis and the photophysical characterization of a series of luminescent neutral Pt(II) compounds containing a tridentate dianionic N-donor chromophoric ligand and a monodentate ancillary moiety. The compounds exhibited notable change of the photoluminescence properties upon self-assembly due to the establishment of weak non-covalent intermolecular interactions – metal-metal and π-π. We demonstrated how Pt(II) complexes can be self-assembled in a controlled and precise manner by playing with kinetic and thermodynamic factors and the morphology of the different assemblies investigated. Such approaches led to materials with enhanced and unique properties such as mechanochromism and polarized light absorption and emission. The investigated compounds and their assemblies were useful for the development of novel functional supramolecular materials in and out of the equilibrium as well as for bioimaging application

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Veselska, Oleksandra. "Études Structurales et Photophysiques de Polymères de Coordination de Thiolates de Métaux Monétaires." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1197/document.

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Les polymères de coordination (PCs) à base de thiolates de métaux monétaires sont bien connus pour leurs propriétés luminescentes. Cependant, leurs structures sont sous-explorées. Dans cette thèse, nous présentons une étude pionnière visant la compréhension de la formation de la structure et de la corrélation ‘structure-propriétés’ des PCs homoleptiques neutres, [M(SR)]n, M = Cu(I), Ag(I), Au(I). Les composés avec les dérivés du thiophénolate étudiés dans ce travail, illustrent comment l'utilisation de certains ligands organiques fonctionnalisés conduit à la formation de réseaux 2D étendus ou de colonnes 1D par l'addition d'un encombrement stérique. De plus, la première étude structurelle comparative des PCs thiolées amorphes a été réalisée par analyse PDF. Les études photophysiques ont montré la diversité des propriétés luminescentes des PCs à base de thiolates de métaux monétaires. Des pics d'émission doubles ou multiples, un rendement quantique élevé, des émetteurs orange à proche infrarouge, des variations significatives de durée de vie en fonction de la température... toutes ces propriétés intrinsèques révèlent le potentiel élevé de ces composés pour diverses applications optiques The coordination polymers (CPs) based on thiolates of coinage metals are well known for their luminescence properties. However, their structures stayed underexplored. In the thesis we present a pioneering study targeting the understanding of the structure formation and the ‘structure-properties’ correlation for neutral homoleptic CPs, [M(SR)]n, M = Cu(I), Ag(I), Au(I). The compounds with thiophenolate derivatives studied in the work, illustrate how the use of some functionalized organic ligands leads to the formation of extended 2D networks or 1D columns by addition of some steric hindrance. The first comparative structural study of amorphous thiolated CPs was performed by PDF analysis. The photophysical studies showed the diversity of luminescent properties of the CPs based on thiolates of coinage metals. Double or multiple emission peaks, high quantum yield of orange-toinfrared emitters, significant lifetime variation with temperature… all of these intrinsic properties reveal the high potential of these compounds for diverse optical applications

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Camacho, González Francisco. "Charge-Storage mechanisms in polymer electrets." Phd thesis, Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2006/875/.

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In view of the importance of charge storage in polymer electrets for electromechanical transducer applications, the aim of this work is to contribute to the understanding of the charge-retention mechanisms. Furthermore, we will try to explain how the long-term storage of charge carriers in polymeric electrets works and to identify the probable trap sites. Charge trapping and de-trapping processes were investigated in order to obtain evidence of the trap sites in polymeric electrets. The charge de-trapping behavior of two particular polymer electrets was studied by means of thermal and optical techniques. In order to obtain evidence of trapping or de-trapping, charge and dipole profiles in the thickness direction were also monitored. In this work, the study was performed on polyethylene terephthalate (PETP) and on cyclic-olefin copolymers (COCs). PETP is a photo-electret and contains a net dipole moment that is located in the carbonyl group (C = O). The electret behavior of PETP arises from both the dipole orientation and the charge storage. In contrast to PETP, COCs are not photo-electrets and do not exhibit a net dipole moment. The electret behavior of COCs arises from the storage of charges only. COC samples were doped with dyes in order to probe their internal electric field. COCs show shallow charge traps at 0.6 and 0.11 eV, characteristic for thermally activated processes. In addition, deep charge traps are present at 4 eV, characteristic for optically stimulated processes. PETP films exhibit a photo-current transient with a maximum that depends on the temperature with an activation energy of 0.106 eV. The pair thermalization length (rc) calculated from this activation energy for the photo-carrier generation in PETP was estimated to be approx. 4.5 nm. The generated photo-charge carriers can recombine, interact with the trapped charge, escape through the electrodes or occupy an empty trap. PETP possesses a small quasi-static pyroelectric coefficient (QPC): ~0.6 nC/(m²K) for unpoled samples, ~60 nC/(m²K) for poled samples and ~60 nC/(m²K) for unpoled samples under an electric bias (E ~10 V/µm). When stored charges generate an internal electric field of approx. 10 V/µm, they are able to induce a QPC comparable to that of the oriented dipoles. Moreover, we observe charge-dipole interaction. Since the raw data of the QPC-experiments on PETP samples is noisy, a numerical Fourier-filtering procedure was applied. Simulations show that the data analysis is reliable when the noise level is up to 3 times larger than the calculated pyroelectric current for the QPC. PETP films revealed shallow traps at approx. 0.36 eV during thermally-stimulated current measurements. These energy traps are associated with molecular dipole relaxations (C = O). On the other hand, photo-activated measurements yield deep charge traps at 4.1 and 5.2 eV. The observed wavelengths belong to the transitions in PETP that are analogous to the π - π* benzene transitions. The observed charge de-trapping selectivity in the photocharge decay indicates that the charge detrapping is from a direct photon-charge interaction. Additionally, the charge de-trapping can be facilitated by photo-exciton generation and the interaction of the photo-excitons with trapped charge carriers. These results indicate that the benzene rings (C6H4) and the dipolar groups (C = O) can stabilize and share an extra charge carrier in a chemical resonance. In this way, this charge could be de-trapped in connection with the photo-transitions of the benzene ring and with the dipole relaxations. The thermally-activated charge release shows a difference in the trap depth to its optical counterpart. This difference indicates that the trap levels depend on the de-trapping process and on the chemical nature of the trap site. That is, the processes of charge detrapping from shallow traps are related to secondary forces. The processes of charge de-trapping from deep traps are related to primary forces. Furthermore, the presence of deep trap levels causes the stability of the charge for long periods of time. Angesichts der Bedeutung der Ladungsspeicherung in Polymerelektreten für viele Anwendungen, wie z.B. in elektromechanischen Wandler, ist es das Ziel dieser Arbeit, zum Verständnis der zugrundeliegenden Mechanismen der kurz- und langfristigen Ladungsstabilisierung beizutragen sowie mögliche Haftstellen zu identifizieren. Ladungs- und Entladungsprozesse in Elektreten geben Hinweise auf Ladungshaftstellen. Diese Prozesse wurden mit thermischen und optischen Methoden bei gleichzeitiger Messung von Ladungs- und Polarisationprofilen untersucht. Die experimentellen Untersuchungen der vorliegenden Arbeit wurden an Polyethylenterephthalat (PETP) und an Cyclischen-Olefin Copolymeren (COC) durchgeführt. PETP ist ein Photoelektret und weist in der Carbonylgruppe (C = O) ein Dipolmoment auf. Die Elektreteigenschaften ergeben sich sowohl aus der Orientierungspolarisation als auch aus der Ladungsspeicherung. Im Gegensatz zu PETP ist COC kein Photoelektret und zeigt auch keine Orientierungspolarisation. Deshalb folgen die Elektreteigenschaften des COC ausschließlich aus der Ladungsspeicherung. Die COC-Proben wurden mit Farbstoffen dotiert, um das innere elektrische Feld zu untersuchen. Diese Systeme zeigen flache Ladungshaftstellen bei 0,6 und 0,11 eV, die durch thermisch stimulierte Prozesse entladen werden sowie tiefe Haftstellen bei 4 eV, die optisch stimuliert werden können. PETP-Filme zeigen einen transienten Photostrom mit einem Maximalwert ( jp), der von der Temperatur mit einer Aktivierungsenergie von 0,106 eV abhängt. Der thermische Paarabstand (rc) kann für die Photoladungsgeneration in PETP auf ca. 4,5 nm abgeschätzt werden. Die Photoladungsträger können rekombinieren, mit den gespeicherten Ladungen interagieren, über die Elektroden entkommen oder eine leere Haftstelle einnehmen. PETP zeigt einen kleinen quasi-statischen pyroelektrischen Koeffizienten (QPC) von ca. 0,6 nC/(m²K) für nicht polarisierte Proben, ca. 60 nC/(m²K) für polarisierte Proben und ca. 60 nC/(m²K) für nicht polarisierte Proben mit Vorspannung (E ~10 V/µm). Wenn die gespeicherten Ladungen ein internes elektrisches Feld von ca. 10 V/µm generieren können, sind sie in der Lage, einen QPC herbeizuführen, der vergleichbar mit dem von orientierten Dipolen ist. Es ist außerdem möglich, eine Ladungs-Dipol-Wechselwirkung zu beobachten. Da die QPM-Daten von PETP auf Grund des geringen Signals verrauscht sind, wurde ein numerisches Fourier-Filterverfahren angewandt. Simulationen zeigen, dass eine zuverlässige Datenanalyse noch bei einem Signal möglich ist, dessen Rauschen bis zu 3-mal größer ist als der berechnete pyroelektrische Strom. Messungen der thermisch stimulierten Entladung von PETP-Filmen ergaben flache Haftstellen bei ca. 0,36 eV, welche mit der Dipolrelaxation der Carbonylgruppe (C = O) assoziiert sind. Messungen der photostimulierten Entladung ergaben tiefe Haftstellen bei 4,1 und 5,2 eV. Die beobachteten Wellenlängen entsprechen Übergängen in PETP analog den π - π* Übergängen in Benzol. Die beobachtete Selektivität bei der photostimulierten Entladung lässt auf eine direkte Wechselwirkung von Photonen und Ladungen schließen. Einen zusätzlichen Einfluß auf die Entladung hat die Erzeugung von Photo-Exzitonen und deren Wechselwirkung mit den gespeicherten Ladungsträgern. Diese Ergebnisse deuten darauf hin, dass die Phenylringe (C6H4) und die Dipolgruppen (C = O) eine zusätzliche Ladung in einer chemischen Resonanz stabilisieren und miteinander teilen können. Daher kann die gebundene Ladung auch durch einen Photoübergang im Benzolring oder durch eine Dipolrelaxation freigesetzt werden. Die mittels thermisch stimulierter Entladung bestimmte Tiefe der Haftstellen unterscheidet sich deutlich von den mittels photostimulierter Entladung gemessenen Werten. Flachere Haftstellen werden bei der thermisch stimulierten Entladung gefunden und können sekundären Kräften zugeordnet werden. Die tieferen Haftstellen sind chemischer Natur und können primären Kräften zugeordnet werden. Letztere sind für die Langzeitstabilität der Ladung in Polymerelektreten verantwortlich.

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Ivy, Joshua F. "Optoelectronically Active Metal-Inorganic Frameworks and Supramolecular Extended Solids." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248495/.

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Metal-organic frameworks (MOFs) have been intensely researched over the past 20 years. In this dissertation, metal-inorganic frameworks (MIFs), a new class of porous and nonporous materials using inorganic complexes as linkers, in lieu of traditional organic linkers in MOFs is reported. Besides novel MIF regimes, the previously described fluorous MOF "FMOF-1", is re-categorized herein as "F-MIF1". F-MIF-1 is comprised of [Ag4Tz6]2- (Tz = 3,5-bis-trifluoromethyl-1,2,4-triazolate) inorganic clusters connected by 3-coordinate Ag+ metal centers. Chapter 2 describes isosteric heat of adsorption studies of F-MIF1 for CO2 at near ambient temperatures, suggesting promise for carbon capture and storage. We then successfully exchanged some of these Ag(I) centers with Au(I) to form an isostructural Au/F-MIF1. Other, nonporous MIFs have been synthesized using Ag2Tz2 clusters with bridging diamine linkers 4,4'-bipyridine, pyrazine, and a Pt(II) complex containing two oppositely-situated non-coordinating pyridines. This strategy attained luminescent products better-positioned for photonic devices than porous materials due to greater exciton density. Chapter 3 overviews work using an entirely inorganic luminescent complex, [Pt2(P2O5)4]4- (a.k.a. "PtPOP") to form new carbon-free MIFs. PtPOP is highly luminescent in solution, but as a solid shows poor quantum yield (QY ~0.02) and poor stability under ambient conditions. By complexing PtPOP to various metals, we have shown a dramatic enhancement in its solid-state luminescence (by an order of magnitude) and stability (from day to year scale). One embodiment (MIF-1) demonstrates microporous character. Chapter 4 overviews the design and application of new MIF linkers. Pt complexes based upon (pyridyl)azolates, functionalized with carboxylic acid groups, have been synthesized. These complexes, and their esterized precursors, show strong luminescence on their own. They have been used to generate new luminescent MIFs. Such new MIFs may be useful toward future inorganic (LEDs) or organic (OLEDs) light-emitting diodes, respectively. The electronic communication along their infinite coordination structures is desirable for color tuning and enhanced conductivity functions, compared to the small molecules used in such technologies, which rely on intermolecular interactions for these functions.

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Nishikawa, Tsuyoshi. "Screw-sense Control of Helical Poly(quinoxaline-2,3-diyl)s for Chirality-switchable Asymmetric Catalysts and Luminescent Materials." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225637.

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Forster, Pedro Lima. "Desenvolvimento de sistemas híbridos luminescentes - Polímero:európio(III) com estabilidade térmica e fotoluminescente." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-05092016-131838/.

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O polímero de policaprolactona (PCL) dopado com [Eu (TTA) 3 (H2O) 2] no complexo 1, 2, 5, 10 e 15% de concentrações foram preparadas e as suas propriedades térmicas e de luminescência discutidas. As bandas de absorção de infravermelho no intervalo de 1800-1550 cm-1 correspondente ao ν sensível (C = O) foram seleccionados para a técnica de ajuste de curva de desconvolução e confirmou-se que os picos de componentes são deslocados gradualmente com o aumento da concentração de dopagem. O deslocamento do ν (C = O) banda para os β-dicetonato complexos para novas posições nos sistemas dopados (pCLE) proporcionam boa evidência de que o ião de metal está coordenado aos átomos de oxigénio dos grupos carbonilo PCL. Calorimetria exploratória diferencial (DSC) não mostraram alterações significativas na segunda temperatura de fusão (Tm2) para as amostras de cinema. No entanto, a cristalinidade é afectada pelo complexo dopante em materiais de polímero em maior concentração. A análise termogravimétrica (TGA) não mostra nenhuma perda de peso na gama de 50-200 ° C para os sistemas poliméricos dopados, corroborando a interacção da matriz de polímero com Eu3 + complexo n por substituição das moléculas de água no complexo precursor. A observação das bandas de emissão característicos resultantes das transições 5D0 → 7FJ (J = 0-4) dominadas pela hipersensibilidade transição 5D0 → 7F2 em torno de 614 nm, de íon Eu3 +, indicando que a incorporação de Eu3 + complexo no sistema de polímero. O valor da eficiência quântica de emissão de nível 5D0 para os materiais poliméricos dopados (η = 40-62%) são mais elevados do que para o complexo [Eu (TTA) 3 (H2O) 2] complexo (η = 29%), sugerindo que o matriz de polímero actua como co-sensibilizador do processo de luminescência. The polycaprolactone (PCL) polymer doped with [Eu(tta)3(H2O)2] complex at 1, 2, 5, 10 and 15 % concentrations were prepared and their thermal and luminescence properties discussed. The IR absorption bands in the range of 18001550 cm1 corresponding to the sensitive ν(C=O) were selected for the deconvolution curve-fitting technique and was confirmed that the component peaks are gradually shifted with the increase of doping concentration. The displacement of the ν(C=O) band for the β-diketonate complex to new positions in doped systems (PCLE) provide good evidence that the metal ion is coordinated to the oxygen atoms from the PCL carbonyl groups. Differential scanning calorimetry (DSC) showed no significant changes in second melting temperature (Tm2) for the film samples. However, crystallinity is affected by the dopant complex in the polymer materials at higher concentration. Thermogravimetric analysis (TGA) shows no weight loss in the range of 50200 °C for the doped polymeric systems, corroborating the interaction of the polymer matrix with the Eu3+-complex by substitution of the water molecules in the complex precursor. The observation of the characteristic emission bands arising from the 5D0 → 7FJ transitions (J=0-4) dominated by the hypersensitive 5D0 → 7F2 transition at around 614 nm of Eu3+ ion, indicating the incorporation of the Eu3+ complex in the polymer system. The value of the emission quantum efficiency of 5D0 level for the doped polymer materials (η = 40 - 62 %) are higher than for the [Eu(TTA)3(H2O)2] complex (η = 29 %), suggesting that the polymer matrix acts as co-sensitizer of the luminescence process.

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Kage, Daniel [Verfasser], Stefan [Gutachter] Kirstein, Oliver [Gutachter] Benson, and Michael [Gutachter] Kumke. "Studies on fluorophore-loaded polymer microbeads and luminescence lifetime encoding in flow cytometry / Daniel Kage ; Gutachter: Stefan Kirstein, Oliver Benson, Michael Kumke." Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1198207000/34.

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Santos, Osmar de Sousa [UNESP]. "Desenvolvimento e caracterização de dispositivos de visualização eletroluminescentes." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/91887.

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Made available in DSpace on 2014-06-11T19:25:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-03-28Bitstream added on 2014-06-13T19:12:18Z : No. of bitstreams: 1 santos_os_me_rcla.pdf: 3117713 bytes, checksum: 1d1db67d9cfbf3209f6ce4e1345fedb0 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Com o progresso da ciência e da tecnologia, a cada ano, torna-se cada vez mais freqüente o estudo e a aplicação de novos materiais. Um exemplo de aplicação destes novos materiais são os mostradores e dispositivos luminescentes, e.g., LCDs, OLEDs, PDPs. Visto a importância e a aplicabilidade dos mostradores em nossa sociedade, propomos para este trabalho a construção de um mostrador de sete-segmentos e dispositivos eletroluminescentes. Tendo o objetivo traçado, fez-se um mostrador de sete-segmentos de um compósito polimérico de poli(o-metoxianiliana) (POMA) protonada com ácido ρ-tolueno sulfônico (TSA), poli(fluoreto divinilideno-co-trifluor etileno) (P(VDF-TrFE)) e micro partículas de Zn2ZSi04:Mn. Para os dispositivos eletroluminescentes os materiais utilizados foram: POMA, P(VDF-TrFE), Zn2Si04:Mn, ZnS:Ag, Y2O2S:Eu, Y203:Eu, ZnAl204:Tb, ZnAl204:Eu e Y2Si05:Ce. A análise das amostras empregadas nesta dissertação, com base em técnicas conhecidas da literatura como: microscopia eletrônica de varredura, medidas de impedância e espectroscópicas propiciaram um maior entendimento sobre os processos relacionados à operação, construção e morfologia dos dispositivos e mostradores. Tais parâmetros foram fundamentais para nortear a confecção das amostras, e.g., relação entre a massa de POMA na blenda e a aderencia ao substrato de ITO. As amostras contendo P(VDFTrFE)/(Zn2Si04:Mn ou ZnS:Ag)/P(VDF-TrFE) apresentaram luminescência por aproximadamente 48 minutos na região espectral correspondente a cor verde e azul, respectivamente. Há de se destacar o dispositivo flexível luminoso feito de P(VDFTrFE)/ZnS:Ag/P(VDF-TrFE), confeccionada sem o uso do substrato de ITO, apresentando um pico de emissao luminosa situado no comprimento de onda de 480 nm. With the progress of science and technology, new materials in condensed matters are available to be applied at the industry and science. An example of such application is the new displays and luminescent devices available at the market such as: OLEDs, LCDs and PDPs. The goal of this work is to construct a display of seven-segments and luminescent devices. A seven-segment display was made of polymeric composite, poly(o-methoxyaniline) (POMA) doped with ρ-toluene sulfonic acid (TSA), and poly(vinylidene fluoride-trifluorethylene) (P(VDF-TrFE), in which micro particles of willemite doped with manganese, (Zn2Si04:Mn), was added to the blend. For the luminescent devices the materials used were POMA, P(VDF-TrFE), Zn2Si04:Mn, ZnS:Ag, Y202S:Eu, Y203:Eu, ZnAl2O4:Tb, ZnAl204:EU e Y2Si05:Ce. The analyses of the samples used in this work, based on previous literature and techniques such as: scanning electron microscopy, impedance measurement and spectroscopy yielded an understanding of the process involved in construction, morphology and operation of the devices and the displays. Such parameters were fundamentals to lead the way to how to construct the sample, e.g., the relation between mass of POMA in blend and the adherence to substrate of ITO. The samples made of P(VDF- TrFE)/(Zn2Si04:Mn or ZnS:Ag)/P(VDF-TrFE) shown luminescence approximately for 48 minutes in the correspondent spectral range to green and blue colors, respectively. It is interesting to detach de flexible luminescent device made of (VDF-TrFE)/ZnS:Ag/P(VDF-TrFE) without ITO substrate, which shown a peak of emission to wavelength of 480 nm. The devices made of POMA/P(VDF-TrFE)/Zn2Si04:Mn shown luminescence approximately for 1100 minutes, which it was observed a high dependence of the luminescent intensity with the thickness of devices.

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19

Ashoka, Sahadevan Suchithra. "Anilate-based molecular building blocks for metal-organic frameworks and molecular conductors Conducting Anilate-Based Mixed-Valence Fe(II)Fe(III) Coordination Polymer: Small-Polaron Hopping Model for Oxalate-Type Fe(II)Fe(III) 2D Networks Nanosheets of Two-Dimensional Neutral Coordination Polymers Based on Near-Infrared-Emitting Lanthanides and a Chlorocyananilate Ligand." Thesis, Angers, 2019. http://bu.univ-angers.fr/Contact.

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Ce travail porte sur la synthèse et la caractérisation de matériaux moléculaires fonctionnels basés sur la molécule anilate et présentant des propriétés de conductivité, de magnétisme et de luminescence. Les anilates sont des dérivés de la 2,5-dihydroxy-1,4-benzoquinone substitués en positions 3 et 6 par une variété d’éléments (H, F, Cl, Br, I, CN, etc). Parmi eux, le seul composé hétérosubstitué ClCNAn2- a été choisi pour préparer une nouvelle famille de polymères de coordination bidimensionnels (PC 2D) avec des métaux de transition ou des ions lanthanides : i) un PC à valence mixte FeIIFeIII, de formule [TAG][FeIIFeIII(ClCNAn)3], contient pour la première fois le cation triaminoguanidinium dans un réseau de coordination.ii) Des PC basés sur le ligand ClCNAn2- et des ions lanthanides émettant dans le proche infrarouge (YbIII, NdIII, ErIII). Ces composés ont été exfoliés en monocouches, et des études de photoluminescence ont été menées à la fois sur les cristaux et les monocouches. iii) Une famille de PC hétéroleptiques basés sur des ions lanthanides et sur deux types de ligands pontants, le ligand ClCNAn2- et des ligands de type carboxylates (DOBDC et F4-BDC). iv) Une famille de PC basés sur des ions DyIII ont été préparés afin d’étudier leur propriétés magnétiques. v) Finalement, la capacité des ligands anilates à se combiner à des conducteurs moléculaires basés sur le BEDT-TTF a été démontrée à travers la synthèse et l’électrocristallisation de semiconducteurs organiques et de conducteurs magnétiques hybrides avec l’anion [Fe(ClCNAn)3]3- This work reports on the design, synthesis and characterization of novel anilate-based functional molecular materials showing luminescent, magnetic and/or conducting properties. The family of anilate ligands comprises several derivatives obtained by introducing various substituents (H, F, Cl, Br, I, CN, etc.) at the 3 and 6 positions of the common 2,5-dihydroxy-1,4-benzoquinone framework. Among the anilate ligands, the only known heterosubstituted anilate with Cl/CN substituents at the 3,6 positions, ClCNAn2-, have been selected for preparing a novel family of 2D layered coordination polymers (2D CP) with both 3d metal ions and 4f lanthanide ions, through a general and straightforward synthetic strategy. i) Mixed-valence FeIIFeIII 2D CP, formulated as [TAG][FeIIFeIII(ClCNAn)3], containing, the tris(amino)-guanidinium (TAG) cation for the first time in such 2D networks has been synthesized and thoroughly characterized. ii) 2D CPs based on NIR-emitting lanthanides (YbIII, NdIII, ErIII) and the ClCNAn2- ligand, have been prepared and characterized. These layered compounds were exfoliated to nanosheets, by sonication-assisted solution synthesis. Time-resolved photoluminescence studies performed on both the bulk and nanosheets are also highlighted. iii) Novel family of heteroleptic 2D CPs based on NIR-emitting lanthanides and mixed ligands (ClCNAn2- and carboxylate ligands (DOBDC and F4-BDC)), were prepared and characterized. vi) Novel family of 2D CPs based on DyIII and ClCNAn2- were prepared in order to investigate their magnetic properties. v) Furthermore, the ability of anilate ligands to work as components of BEDT-TTF- based molecular conductors have been demonstrated through the synthesis, via electrocrystallization technique. vi) П-d hybrid multifunctional paramagnetic molecular conductors BEDT-TTF and [Fe(ClCNAn)3]3-) were also studied

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20

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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21

Adamson, Philip George. "Luminescence studies of water-soluble polymers." Thesis, Lancaster University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428737.

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22

Fan, Xiao. "Heterometallic coordination polymers : toward luminescence modulation." Thesis, Rennes, INSA, 2015. http://www.theses.fr/2015ISAR0007/document.

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Les polymères de coordination décrits dans cette thèse ont été préparés en accord avec les concepts de la chimie verte par réactions dans l’eau entre les sels de sodium des ligands et les ions lanthanides compris entre La et Lu (sauf Pm) plus Y. Deux types d’échantillons ont été préparés : des monocristaux et des poudres microcristallines. Les structures cristallines ont été résolues sur la base des monocristaux et les poudres microcristallines ont été utilisées pour étudier les propriétés physicochimiques des composés : stabilité thermique, propriétés de luminescence et de magnétisme. Dans nos travaux, quatre systèmes de polymères de coordination ont été étudiés. Ils ont été obtenus à partir de quatre acides : acide chelidonique (H2cda), acide 5-hydroxy-isophthalique (H2hip), acide 5-nitroisophthalique (H2nip) et acide 4-carboxyphenylboronique (Hcpb). Dix nouveaux monocristaux ont été obtenus par diffusions lentes en tubes en U à travers des gels physique (Agar) ou chimiques (TMOS ou TEOS), par diffusion lente en tubes en H à travers de l’eau distillée ou par évaporation lente du filtrat obtenu après la synthèse des poudres microcristallines. Les poudres microcristallines ont été classées sur la base de leurs diagrammes de diffraction des rayons-X. Leurs propriétés de luminescence ou de magnétisme ont été étudiées à l’état solide. Les transferts d’énergie intermétalliques ont été discutés, en particulier pour les ligands H2hip et Hcpb. Les composés hétéro-nucléaires (Gd / Tb et Eu / Tb) ont été préparés pour moduler les propriétés luminescentes de ces composés en variant les proportions relatives en ions lanthanides. Les polymères de coordination à base de terres rares synthétisés et étudiés dans ce manuscrit fournissent des informations intéressantes pour la conception future de matériaux multifonctionnels According to the concepts of Green Chemistry, the coordination polymers based on lanthanide ions were prepared by reactions in water between the sodium salts of ligands and lanthanide ions comprised between La and Lu (except Pm) plus Y. Two kinds of samples were prepared : single crystals and microcrystalline powders. The former ones are used to determine the single crystal structure, and the later ones are used to measure the physical-chemical properties : thermal stability, luminescence and magnetism properties. In our work, four ligands were explored: chelidonic acid (H2cda), 5-hydroxy-isophthalic acid (H2hip), 5-nitroisophthalic acid (H2nip) and 4-carboxyphenylboronic acid (Hcpb). As a result, 10 new single crystals were obtained by slow diffusion in U-shape tubes through physical gel (agar) or chemical gels (TMOS or TEOS), by slow diffusion in H-shape tubes through distilled water or by evaporation of the filtrate obtained after the synthesis of the microcrystalline powders. Microcrystalline powders were classified on the basis of their X-ray powder diffraction patterns. Their luminescent properties and magnetic properties were studied in the solid state. Intermetallic energy transfers were also discussed. Especially, for ligands H2hip and H2cpb. Hetero-nuclear compounds (Gd/Tb and Eu/Tb) were also prepared to tune luminescent properties by changing the relative ratios of the lanthanide ions. Lanthanide coordination polymers described in this thesis provide information that could be useful as far as multifunctional materials are targeted

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Santos, Osmar de Sousa. "Desenvolvimento e caracterização de dispositivos de visualização eletroluminescentes /." Rio Claro : [s.n.], 2008. http://hdl.handle.net/11449/91887.

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Orientador: Dante Luis Chinaglia Banca: Marian Rosaly Davolos Banca: Lucas Fugikawa Santos Resumo: Com o progresso da ciência e da tecnologia, a cada ano, torna-se cada vez mais freqüente o estudo e a aplicação de novos materiais. Um exemplo de aplicação destes novos materiais são os mostradores e dispositivos luminescentes, e.g., LCDs, OLEDs, PDPs. Visto a importância e a aplicabilidade dos mostradores em nossa sociedade, propomos para este trabalho a construção de um mostrador de sete-segmentos e dispositivos eletroluminescentes. Tendo o objetivo traçado, fez-se um mostrador de sete-segmentos de um compósito polimérico de poli(o-metoxianiliana) (POMA) protonada com ácido ρ-tolueno sulfônico (TSA), poli(fluoreto divinilideno-co-trifluor etileno) (P(VDF-TrFE)) e micro partículas de Zn2ZSi04:Mn. Para os dispositivos eletroluminescentes os materiais utilizados foram: POMA, P(VDF-TrFE), Zn2Si04:Mn, ZnS:Ag, Y2O2S:Eu, Y203:Eu, ZnAl204:Tb, ZnAl204:Eu e Y2Si05:Ce. A análise das amostras empregadas nesta dissertação, com base em técnicas conhecidas da literatura como: microscopia eletrônica de varredura, medidas de impedância e espectroscópicas propiciaram um maior entendimento sobre os processos relacionados à operação, construção e morfologia dos dispositivos e mostradores. Tais parâmetros foram fundamentais para nortear a confecção das amostras, e.g., relação entre a massa de POMA na blenda e a aderencia ao substrato de ITO. As amostras contendo P(VDFTrFE)/(Zn2Si04:Mn ou ZnS:Ag)/P(VDF-TrFE) apresentaram luminescência por aproximadamente 48 minutos na região espectral correspondente a cor verde e azul, respectivamente. Há de se destacar o dispositivo flexível luminoso feito de P(VDFTrFE)/ZnS:Ag/P(VDF-TrFE), confeccionada sem o uso do substrato de ITO, apresentando um pico de emissao luminosa situado no comprimento de onda de 480 nm. Abstract: With the progress of science and technology, new materials in condensed matters are available to be applied at the industry and science. An example of such application is the new displays and luminescent devices available at the market such as: OLEDs, LCDs and PDPs. The goal of this work is to construct a display of seven-segments and luminescent devices. A seven-segment display was made of polymeric composite, poly(o-methoxyaniline) (POMA) doped with ρ-toluene sulfonic acid (TSA), and poly(vinylidene fluoride-trifluorethylene) (P(VDF-TrFE), in which micro particles of willemite doped with manganese, (Zn2Si04:Mn), was added to the blend. For the luminescent devices the materials used were POMA, P(VDF-TrFE), Zn2Si04:Mn, ZnS:Ag, Y202S:Eu, Y203:Eu, ZnAl2O4:Tb, ZnAl204:EU e Y2Si05:Ce. The analyses of the samples used in this work, based on previous literature and techniques such as: scanning electron microscopy, impedance measurement and spectroscopy yielded an understanding of the process involved in construction, morphology and operation of the devices and the displays. Such parameters were fundamentals to lead the way to how to construct the sample, e.g., the relation between mass of POMA in blend and the adherence to substrate of ITO. The samples made of P(VDF- TrFE)/(Zn2Si04:Mn or ZnS:Ag)/P(VDF-TrFE) shown luminescence approximately for 48 minutes in the correspondent spectral range to green and blue colors, respectively. It is interesting to detach de flexible luminescent device made of (VDF-TrFE)/ZnS:Ag/P(VDF-TrFE) without ITO substrate, which shown a peak of emission to wavelength of 480 nm. The devices made of POMA/P(VDF-TrFE)/Zn2Si04:Mn shown luminescence approximately for 1100 minutes, which it was observed a high dependence of the luminescent intensity with the thickness of devices. Mestre

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24

Ammora, Ayham Awad. "Novel polymer-based luminescent pigments." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621865.

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25

Levell, Jack William. "Material and device design for organic optoelectronics." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2066.

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This thesis describes investigations into the photophysical properties of luminescent materials and their application in optoelectronic devices such as light emitting diodes and photodetectors. The materials used were all solution processable because of the interest in low cost processing of organics. I have investigated the photophysics of 1,4,5,8,9,12-hexamethyltriphenylene, a triphenylene derivative which has its luminescence enhanced by the addition of methyl groups. These groups change the planar shape of the triphenylene molecule into a twisted one, changing the symmetry of the molecule and increasing its dipole moment in absorption and emission by ~4 fold. This increased its rate of radiative deexcitation by ~20 times. In addition, the twisted shape of the molecule prevents intermolecular interactions and concentration effects from affecting the luminescence. This results in an efficient solid-state photoluminescence quantum yield of 31%. This thesis also includes an investigation into phosphorescent polymer dendrimers, designed to have suitable viscosities in solution for inkjet printed OLED applications. A photophysical study of the intra-chain aggregation effects on the luminescence was undertaken in both homopolymers and copolymers with high energy gap spacer units. Using double dendrons to increase the steric protection of the luminescent cores, the best homopolymers achieved 12.1% external quantum efficiency (39.3 cd/A) at 100 cd/m² brightness and the best co-polymer achieved 14.7% EQE (48.3 cd/A) at 100 cd/m². This compares favourably with 11.8% EQE for the best phosphorescent polymer and 16% for the best solution processed dendrimer OLED previously reported. Finally I have applied a solution processed enhancement layer to silicon photodiodes to enhance their ultraviolet response. Using a blend of materials to give favourable absorption and emission properties, 61% external quantum efficiency was achieved at 200 nm, which is better than the 20-30% typical for vacuum deposited lumogen enhancement layers used commercially.

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26

Nehrlich, Louise. "Luminescence studies of interactions involving water soluble polymers." Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266805.

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27

Banaei, Esmaeil. "Polymer Optical Fibers for Luminescent Solar Concentration." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5898.

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Luminescent solar concentrators (LSC's) are promising candidates for reducing the cost of solar power generation. Conventional LSC's are slab waveguides coated or doped with luminescence materials for absorption and guiding of light to the slab edges in order to convert optical energy into electricity via attached photovoltaic (PV) cells. Exploiting the advantages of optical fiber production, a fiber LSC (FLSC) is presented in this thesis, in which the waveguide is a polymeric optical fiber. A hybrid fiber structure is proposed for an efficient two-stage concentration of incident light, first into a small doped core using a cylindrical micro-lens that extends along the fiber, and second to the fiber ends by guiding the fluoresced light from the active dopants. Flexible sheets are assembled with fibers that can be bundled and attached to small-area PV cells. Small dimensions and directional guiding of the fibers allow for approximately one order of magnitude geometrical gain improvement over that of existing flat LSC's. In addition, the undesired limit of LSC size is eliminated in one direction. Modeling and optimization of an FLSC design is presented using polarization-ray tracing under realistic conditions with solar spectrum radiation and broad-band absorption and emission spectra of fluorescence materials with their inevitable self-absorption effect. Methods and results of fabrication and accurate optical characterization of such FLSC using two off-the-shelf organic dyes and a commercially available polymer, COP, are discussed in detail. Fiber preforms, fabricated under optimized conditions for low light transport loss, are thermally drawn into sub-millimeter-size fibers. Characterization of several samples with various concentrations of the two dyes shows an optical-to-optical conversion efficiency of 9.1% for a tandem combination of two 2.5-cm-long fibers with the efficiency gradually decreasing to 4.9% with increase in fiber length to 10 cm. Ph.D. Doctorate Electrical Engineering and Computer Science Engineering and Computer Science Electrical Engineering

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28

Pathan, Shaheen. "Développement de matériaux flexibles optiquement actifs basés sur des nanostructures hybrides chirales de modèle d’assemblage moléculaire." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0126.

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Dans ce travail, nous nous sommes concentrés sur la création de nanostructures chirales optiquement actives en fabriquant des nanohélices de silice fluorescente afin d’obtenir des matériaux souple, nanométriques, optiquement actifs pour des applications en tant que matériaux nanophotoniques. Dans cette optique, des nanohélices de silice chirales ont été utilisées pour greffer et organiser des nanocristaux inorganiques fluorescents achiraux tels que des quantums dots, des chromophores, des molécules et des polymères fluorescents selon différentes approches. Ces hélices inorganiques ont été formées par procédé sol-gel en utilisant des auto-assemblages hélicoïdaux organiques de molécules amphiphiles (amphiphile gemini cationique, avec un contre-ion chiral le tartrate) en tant que modèles. Tout d'abord, la surface de la silice hélicoïdale a été fonctionnalisée par l’APTES afin de greffer des quantum dots inorganiques ZnS-AgInS2 possédant divers ligands. Dans la deuxième partie, le polymère de dérivé anthracénique fluorescent a été organisé par dépôt et adsorption à la surface de silice hélicoïdale. Afin d’étudier les propriétés chiroptiques, différentes caractérisations ont été réalisées telle que la spectroscopie du dichroïsme circulaire (CD) et celle de la luminescence circulairement polarisée (CPL).Le premier chapitre présente l’étude bibliographique sur différents systèmes d’auto-assemblage organiques chiraux et leurs propriétés chiroptiques. Les études sur la formation de systèmes auto-assemblés chiraux dans différentes conditions, leur morphologie structurale, les techniques de fabrication et leurs applications sont discutées suivies de l'utilisation de nanocristaux fluorescents, à savoir, les quantums dots (QD) et les polymères fluorescents achiraux sur lesquels les propriétés chiroptiques peuvent être obtenues et leurs applications dans les nanodispositifs optiques, les capteurs et la nano-photonique.Dans la première partie du deuxième chapitre, différentes techniques de caractérisation telles que le microscope électronique en transmission (TEM), le microscope électronique en transmission haute résolution (HRTEM), la microscopie confocale, la spectroscopie UV-Vis, celle de la fluorescence, du dichroïsme circulaire (CD) et de la luminescence circulairement polarisée (CPL) sont décrites. Dans la deuxième partie, la synthèse du gemini 16-2-16 ainsi que son mécanisme d'auto-assemblage, et sa transformation en réplica de silice par l'intermédiaire de la chimie sol-gel sont décrits. Ces nanohélices de silice sont fonctionnalisées par le 3-aminopropyltriéthoxysilane (APTES). Leur analyse est effectuée par analyse thermogravimétrique (TGA) et analyse élémentaire (EA).Dans le troisième chapitre, nous nous sommes concentrés sur la synthèse de QDs inorganiques ((ZnS)x-1(AgInS2)x) avec différentes compositions rapport molaire et leurs caractérisations par TEM, TGA, EA, spectroscopie infrarouge à transformée de Fourier (FTIR), mesures de potentiel zêta, spectroscopie d'absorption et d'émission. Quatre types de ligands ont été utilisés, par échange de ligand, pour recouvrir les QDs : sulfure d'ammonium (AS), acide 3-mercaptopropionique (MPA), l-cystéine (L-Cys) et l'oleylamine (OLA). Ces QDs sont greffés à la surface des hélices de silice modifiée par de l’amine suite à des interactions ioniques. Diverses techniques ont été utilisées pour confirmer leur greffage à la surface des hélices de silice, et les propriétés optiques ont été étudiées par spectroscopie d'absorption et d'émission. Après le greffage, différents résultats ont été observés selon le ligand utilisé : la caractérisation par TEM montre que les QDs sont greffés à la surface des hélices de silice. [...] In this work, we focused on the creation of optically active chiral nanostructures by fabricating fluorescent silica nanohelices in order to obtain optically active nanoscale soft materials for applications as nanophotonics materials. For this purpose, silica chiral nanohelices were used for grafting and organizing achiral fluorescent inorganic nanocrystals, dyes, molecules, and fluorescent polymers through different approaches. These inorganic helices were formed via sol-gel method using organic helical self–assemblies of surfactant molecules (achiral and cationic gemini surfactant, with chiral counterion, tartrate) as templates. First, the surface of helical silica was functionalized by APTES in order to graft inorganic quantum dots ZnS-AgInS2 with different capping ligands. In the second part, fluorescent anthracene derivative polymer was organized via deposition and absorption on the surface of helical silica. To investigate the chiroptical properties, circular dichroism and circularly polarised luminescence characterization were performed.In the first chapter, the bibliographic study on different chiral organic self-assembling systems and their chiroptical properties are shown. The studies on the formation of chiral self-assembled systems in different conditions, structural morphology, fabrication techniques and their applications are discussed followed by the use of fluorescent nanocrystals, i.e., quantum dots (QDs) and achiral fluorescent polymers on which chiroptical properties can be obtained and their applications in optical nanodevices, sensors, and nano-photonics.In the first part of the second chapter, different characterisation techniques such as transmission electron microscope (TEM) , high resolution transmission electron microscope (HRTEM), and confocal microscopy, UV-Vis spectroscopy and fluorescence spectroscopies, as well as circular dichroism (CD) and circularly polarised luminescence (CPL) spectroscopies are described. In the second part, the synthesis of Gemini 16-2-16 as well as their self-assemblies mechanism, and their transformation to silica replica via sol-gel chemistry are described. These silica nanohelices are functionalized by 3-aminopropyltriethoxysilane (APTES). Their analysis is performed by Thermogravimetric analysis (TGA) and elementary analysis (EA).In the third Chapter, we focused on the synthesis of inorganic ((ZnS)x-1(AgInS2)x) QDs with different compositions molar ratio and its characterizations by TEM, TGA, EA, Fourier-transform infrared spectroscopy (FTIR), zeta potential measurements, absorption, and emission spectroscopy. Four types of ligands were used to cap the QDs via phase ligand exchange as follows: ammonium sulphide (AS), 3-mercaptopropionic acid (MPA), l-cysteine (L-Cys) and the fourth one is oleylamine (OLA). These QDs are grafted on the surface of amine-modified silica helices through ionic interaction. Various techniques were used to show the grafting of QDs on the surface of silica helix, and their optical properties were studied using absorption and emission spectroscopy. After grafting, in each case of ligands, different results were observed as follows: The TEM characterization shows that QDs are grafted on the surface of silica helices. In the case of AS-capped QDs, the helical morphology of silica helices after grafting is destroyed; therefore the further ananlysis was not possible. While, in the cases of QDs with three other ligands MPA, OLA and L-cys, dense and homogeneous grafting of the QDs were observed by TEM and the helical morphology was preserved after their grafting. The HRTEM images were taken on the MPA-QDs@silica helices and energy-dispersive x-ray (EDX) analysis was performed in STEM mode, confirming the QDs elements present on the silica surfaces. [...]

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29

Nagata, Yuuya. "Synthesis of novel luminescent organoboron polymers." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136307.

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30

Morais, Faustino Bruno Miguel. "Preparation and luminescent properties of nanoparticle-organic polymer composites." Thesis, Kingston University, 2016. http://eprints.kingston.ac.uk/35580/.

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This thesis reports investigations into some photophysical aspects of luminescent nanocomposites in a number of different systems. The preparation of Ln[sup]3+ doped rutile SnO[sub]2 (Ln = Sm, Eu, Tb, Ho, Nd) by a sol-gel method is described. Average particle size was found to be 23nm by x-ray powder diffraction and electron microscopy. Factors affecting growth kinetics are also discussed. Successful sensitisation of Ln[sup]3+ emission via SnO[sub]2 host energy transfer is reported. Optimum Ln[su]3+ concentrations were investigated and a proposed mechanism of Dexter type energy transfer based on SnO[sub]2 lattice defects acting as sensitising centres is presented. The relationship between the Ln ionic radius and the dopant concentration required to maximise its emission is also explored. It was found that the larger the ionic radii, the less Ln[sup]3+ was required to maximise its emission. Investigations into the distance dependence of the energy transfer between Ln[su]3+ and Sn[sup]4+ as well as between neighbouring Ln[su]3+ ions have been undertaken - e.g. it was concluded that maximum Sm[sup]3+ sensitisation occurred when every fourth Sn ion was substituted by Sm. Poly(p-phenylene vinylene) (PPV) was synthesised via the thermal conversion route proposed by Wessling and Zimmerman. Monomers, precursor polymer and polymer were fully characterized by means of infra-red, UV-Vis absorption and photoluminescence spectroscopy. By-products were also characterised by [sup]1H and [sup]3C-NMR. Incorporation of the SnO2:Ln[sup]3+ nanocomposites into PPV was followed by extensive photoluminescent studies. It was found that sensitisation of both polymer and lanthanide was dependent on the system composition and concentration ratios. There was clear evidence to support successful harvesting of PPV non-emissive triplet state energy into useful Ln[sup]3+ photon emission. To better benefit from triplet state population, a poly(vinyl alcohol) (PVA) two-dimensional hydrogen-bonded cage was used to reduce the triplet quenching. A proposed mechanism of energy transfer is described for each system. Finally, poly(2,5-bis(3-sulfonatoproproxy)-1,4-phenylene, disodium salt-alt-1,4-phenylene) (PPP-OPSO[sub]3) was used as a donor, to systematically compare the effect of SnO[sub]2:Ln[sup]3+ nanoparticles on the luminescence of a polymer with a larger band gap and higher triplet state energy. It was established that the high triplet state of PPP-OPSO[sub]3 matched the emissive levels of most lanthanides, and a clear indication of triplet harvesting by Eu[sup]3+ was obtained under oxygen-free conditions in a PVA amtrix. Exchange of the polymer's Na{sup]+ cation by Eu[sup]3+ brought both donor and acceptor into close proximity. Dexter type energy transfer was seen from both singlet and triplet states, with Eu[sup]3+ emission lifetimes as long as 400ms in phosphorescence measurements.

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31

Posavec, Tony. "An Investigation into the Fluorescence of Polymers." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1499353221343727.

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Khan, Amena Lutfa Tabenda. "Analysis of electron-phonon coupling from the luminescence of conjugated polymers." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615099.

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Tyombo, Nolukholo. "Synthesis and Luminescence of Zinc Oxide Nanorods-Blended Thiopheno-Organosilicon Polymers." University of the Western Cape, 2017. http://hdl.handle.net/11394/6230.

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Magister Scientiae - MSc (Chemistry) The increasing cost of fossil fuel energy production and its implication in environmental pollution and climate change created high demand for alternative and renewable sources of energy. This has led to great interest in research in the field of photovoltaic or solar cells Due to the abundance of sunlight, the technology is sustainable, non-polluting and can be implemented at places where power demand is needed, for example in rural areas. Solar cell devices that have been commercialized are currently based on silicon technology, involving the use of monocrystalline, polycrystalline and amorphous silicon. Although they produce highly efficient solar cells, the cost of Si solar cells is too high. Second generation solar cell materials such as cadmium telluride and third generation materials such as perovskites and organic polymers have been receiving much attention recently. However, they lack the efficiency of Si solar cells. This research proposes the development of high energy conservation photovoltaic cells from novel low-cost organosilicon polymers. The aim was to develop novel highly branched organosilane polymers such as poly(3-hexythiophene), polydi(thien-2-yl)dimethylsilane, poly(3-hexyl- [2,2'] bithiophenyl-5-yl)-dimethyl-thiophen-2yl-silane) as electron donors along with zinc oxide nanorod as the electron acceptor which were able to bring the efficiency of the resultant photovoltaic cell close to that of current Si solar cell. 2021-08-31

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Piskun, Nadezhda. "Morphology and structure control of luminescence in light-emitting conjugated polymers." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343233394.

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Rosenberg, Ron S. B. Massachusetts Institute of Technology. "Dye-doped polymer nanoparticles for flexible, bulk luminescent solar concentrators." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81143.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2013. Cataloged from PDF version of thesis. Includes bibliographical references (p. 52-56). Bulk luminescent solar concentrators (LSC) cannot make use of Forster resonance energy transfer (FRET) due to necessarily low dye concentrations. In this thesis, we attempt to present a poly-vinylalcohol (PVA) waveguide containing dye-aggregate polystyrene nanospheres that enable FRET at concentrations below that required for the bulk LSC due to dye confinement. In the aqueous state, the maximum achieved energy transfer efficiency of the dye-doped nanoparticles was found to be 8 7% for lwt%/lwt% doping of Coumarin 1 (C1) and Coumarin 6 (C6). In the solid state, however, energy transfer is lost, reducing to 32.8% and 20.1% respectively for the C1(lwt%)/C6(lwt%) and C1(0.5wt%)/C6(lwt/ ) iterations, respectively. Presumably, the dyes leach out of the polystyrene nanospheres and into the PVA waveguide upon water evaporation during drop casting. by Ron Rosenberg. S.B.

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Exton, S. P. "Synthesis and characterisation of novel luminescent probes." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368774.

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37

San, Jose Benedict Arcena. "Polarized Luminescence and Chiroptical Switching Functionalities of Liquid Crystalline and Chiral Conjugated Polymers." Master's thesis, 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188612.

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38

Marpu, Sreekar B. "Biocompatible Hybrid Nanomaterials Involving Polymers and Hydrogels Interfaced with Phosphorescent Complexes and Toxin-Free Metallic Nanoparticles for Biomedical Applications." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc84243/.

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The major topics discussed are all relevant to interfacing brightly phosphorescent and non-luminescent coinage metal complexes of [Ag(I) and Au(I)] with biopolymers and thermoresponsive gels for making hybrid nanomaterials with an explanation on syntheses, characterization and their significance in biomedical fields. Experimental results and ongoing work on determining outreaching consequences of these hybrid nanomaterials for various biomedical applications like cancer therapy, bio-imaging and antibacterial abilities are described. In vitro and in vivo studies have been performed on majority of the discussed hybrid nanomaterials and determined that the cytotoxicity or antibacterial activity are comparatively superior when compared to analogues in literature. Consequential differences are noticed in photoluminescence enhancement from hybrid phosphorescent hydrogels, phosphorescent complex ability to physically crosslink, Au(I) sulfides tendency to form NIR (near-infrared) absorbing AuNPs compared to any similar work in literature. Syntheses of these hybrid nanomaterials has been thoroughly investigated and it is determined that either metallic nanoparticles syntheses or syntheses of phosphorescent hydrogels can be carried in single step without involving any hazardous reducing agents or crosslinkers or stabilizers that are commonly employed during multiple step syntheses protocols for syntheses of similar materials in literature. These astounding results that have been discovered within studies of hybrid nanomaterials are an asset to applications ranging from materials development to health science and will have striking effect on environmental and green chemistry approaches.

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Faceto, Angelo Danilo. "Simulação dos processos de migração e relexação energética em sistemas orgânicos pi-conjugados emissores de luz." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-06092007-104908/.

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Neste trabalho, o método de Monte Carlo é utilizado para simular o processo de difusão espectral da excitação em um sistema polimérico emissor de luz. A metodologia utilizada incorpora a relaxação energética intramolecular, a migração de energia incoerente entre segmentos conjugados e o processo final que pode ser radiativo (luminescência) ou não-radiativo através de centros supressores da excitação (armadilhas ou defeitos). O principal objetivo é comparar os resultados da simulação e de experimentos envolvendo medidas de absorção, de excitação óptica e de luminescência realizadas no IFSC ao longo dos últimos anos ou provenientes da literatura especializada. Além disso, a simulação pretende elucidar a natureza dos processos fotofísicos em semicondutores orgânicos e testar a validade de teorias analíticas existentes, o que é essencial para a aplicação dessa classe de materiais como dispositivos no futuro. Especial atenção é dada na análise do comportamento temporal da luminescência em sistemas em que o acoplamento dipolar na transferência de energia é realizado entre uma matriz de segmentos conjugados e moléculas aceitadoras (impurezas ou defeitos) distribuídas aleatoriamente. A comparação dos resultados da simulação com os resultados experimentais permitiu comprovar a validade do modelo, do programa utilizado e entender melhor características de parâmetros não conhecidos em polímeros conjugados, como a distribuição energética dos estados eletrônicos e a distribuição de centros supressores de luminescência. Foi possível reproduzir com sucesso os espectros de luminescência, de absorção e de excitação seletiva observados experimentalmente em polímeros conjugados descritos na literatura. Além disso, a simulação permitiu explicar resultados relacionados à diminuição da eficiência da luminescência, ao alargamento e ao deslocamento para o azul das linhas espectrais de emissão de polímero conjugado com o aumento da densidade. Foram obtidas as curvas características de eficiência quântica com a variação da energia de excitação e as características não exponenciais das curvas de intensidade de emissão no tempo. Por fim, foi possível estudar os processos fotofísicos envolvidos em heteroestruturas orgânicas com controle a nível molecular das propriedades de emissão a partir dos processos de transferência de energia tipo Förster (dipolo-dipolo) entre polímeros emissores e azocromóforos. As mudanças dos processos fotofísicos do polímero luminescente se fazem pelo controle posicional/orientacional entre camadas doadoras compostas por moléculas do polímero emissor e camadas receptoras à base de azocorante (receptor). In the present work, the Monte Carlo method is employed to simulate the excitation spectral diffusion process in light emitting polymeric systems. The methodology employed a competition among the internal intra-molecular vibrational relaxation, the inter-molecular incoherent energy transference via Förster mechanism and the final process that may be a radiative emission or a non radiative relaxation through a suppression center. This work main objective is to compare the simulation results with the experiments of absorption, optic excitement and luminescence carried on the IFSC throughout the last years or proceeding from specialized literature. Moreover, the simulation intends to elucidate the nature of the photophysical processes in organic semiconductors and to test the validity of existing theories, what it is essential for the application of this branch of materials as devices in the future. Special attention is given in the analysis of the behavior of the time-resolved luminescence in systems where the energy transfer is carried through a matrix of conjugated segments distributed randomly and acceptor molecules (impurities or defects) coupled by dipole interaction. The comparison of the simulation results with the experimental ones allowed to prove the validity of the model, the used program and to better understand characteristic of parameters for conjugated polymers which are still studied. Different the energy distributions of electronic states, molecular position and orientation are used in order to simulate molecular configurations obtained by different sample preparation methodologies and luminescence suppressor centers. With the simulation, it was possible to reproduce with success the experimental spectra of luminescence, absorption and selective excitation measurements in polymers conjugated described in literature. Besides, the simulation allowed to explain resulted related to the decrease of luminescence efficiency with the increase of the energy of the excitation light, as well as the blue shift and broadening of the spectral lines of conjugated polymer emission with the increase of the density. The characteristic curves of quantum efficiency with the variation of the excitation energy and the not exponential characteristics of the time solved emission intensity curves have been reproduced. Finally, it was possible to study the photophysical processes present in organic heterostructures having molecular level control of the properties of emission via changing the Förster type energy transfer processes between emitting polymers and an azodye. The control photophysical process of the luminescent polymer was accomplished by changing both the orientation and position of the azomolecule in an acceptor layer relative the emitting polymer.

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40

Molapo, Kerileng Mildred. "Electrochemiluminescence and organic electronics of derivatised poly(aniline sulphonic acid) light-emitting diodes." University of the Western Cape, 2011. http://hdl.handle.net/11394/5422.

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>Magister Scientiae - MSc Applications of electrochemiluminescent conjugated polymers offer promising solutions in addressing the problem of light emitting devices. However, the challenging problems that hamper their application in light emitting devices are loss of signal due to diffusion of the electrochemiluminescence (ECL) reagent out of the detection zone, limited ability to repeatedly cycle an individual luminophore and high reagent consumption. In this work, the main objective was to produce conducting polymers with enhanced electrochemiluminescence by tuning the properties of the polymer itself. The electrochemical and photophysical properties of films of polyaniline (PANI) and poly(8-anilino-1- naphthalene sulfonic acids) (PANSA) synthesized through electro- and chemical polymerization methods were also investigated. The electrosynthesis of PANSA undoped and doped with anthracene sulfonic acid (ASA), 1,2-naphthaquinone-4-sulfonic acid (NSA) and carbon nanotubes (CNT) in acid medium was investigated and the cyclic voltammograms (CV) showed the growth of the polymer during polymerization. The CV multiscan characterization displayed that the growth of the polymer was dependent of the scan rate and the three redox couples were observed as indicative of the three redox states of typical polyaniline and its derivatives. The results also showed that the peak currents were diffusion controlled and the electron charge transport coefficient (De) of the electrosynthesized polymers was found to range between 10⁻⁸ and 10⁻⁹ cm² s⁻¹ for PANSA, PANSA-ASA, PANSA-NSA and PANSA-CNT. The De value indicates that the movement of electrons along the polymer chain was averagely fast. The transmission electron microscopy (TEM) was used to investigate the electronic morphology of the polymers and the TEM images showed an intertwinement of tubings which aggregate into a ring with a mixture of tubings and plastic sheets. The chemical synthesis of PANI, PANSA and PANI-NSA was carried out by using monomers analine, 8-anilino-1-naphthalene sulfonic acid, and aniline with 1,2- naphthaquinone-4-sulfonic acid, respectively, using oxidants. All chemically synthesized polymers exhibited quinoid and benzoid bands typically see in polyaniline FTIR and Raman spectra confirmed the successfully formation of polymers. The CV characterization of these polymers showed distinctive redox peaks. This proved that the polymers were electroactive, conductive and exhibited reversible electrochemistry. The De of the electrosynthesized polymers was found to be ~10⁻⁵ cm² s⁻¹ for chemically synthesized polymers. The electric conductivity measurement showed to increase from 10⁻⁴ to 10⁻² when aniline was polymerized with NSA dopant, this might be related to the process of electron transfer from dopant to polymer. Scanning electron microscopy for external morphology showed that the polymers were made of different nano- rods polymeric structures. Photophysical properties of electro- and chemically synthesized PANSA and PANI were investigated through UV-vis absorption, fluorescence behaviour, and lifetime. The UV-vis absorption spectra of these polymers showed that they exhibited absorption bands corresponding to the polyemeraldine redox state of typical polyaniline. The effect of dopants resulted in the increase in solubility of the polymers with a small shift of absorption bands due to incorporation of dopants in to the backbone of the polymer. The fluorescence emission spectra of the electrochemically synthesized PANSA with and without dopants were observed to be similar and mirror image of the excitation spectra and corresponding to the electronic band of the benzoid ring in the polyemeraldine form confirming that the fluorescing molecule in these polymers were the benzoid rings. However, the emission spectra of the chemically synthesized PANSA and PANI were different to excitation spectra due to loss of symmetry upon excitation. The effects of chemically synthesized PANI, PANSA and PANI-NSA addition on the photophysical properties of [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂) were investigated in order to understand the interaction of polymer and [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂. The analysis revealed that the presence of polyaniline and its derivatives enhanced the [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)2 absorption band, photoluminescence and fluorescence lifetime. The enhancement observed from interaction of [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂ with polyaniline and its derivatives might be due to the excited state electron transfer from the PANI and PANSA excited state to the [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂. It was further demonstrated in this work that it is possible to form polyaniline and PANSA doped with [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂ films on ITO electrode using potentiostatic growth method to favour ECL production. The results showed that all films generated ECL in the presence of Tripropylamine (TPA) as a co-reactant and their emission properties depend on time used to prepare the film. The enhancement of ECL signal was due to a positive electron transfer from the conducting polymer (PANI and PANSA) to [Ru(bpy)₂(picCOOH)]²⁺.(ClO₄⁻)₂ complex. The results highlighted the potential of these polymeric luminophores usage in the manufacturing of the ECL devices.

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Xu, Shunqi, Yungui Li, Bishnu P. Biswal, et al. "Luminescent sp²-Carbon-Linked 2D Conjugated Polymers with High Photostability." American Chemical Society, 2020. https://tud.qucosa.de/id/qucosa%3A73362.

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Luminescent organic materials with high photostability are essential in optoelectronics, sensor, and photocatalysis applications. However, small organic molecules are generally sensitive to UV irradiation, giving rise to chemical decompositions. In this work, we demonstrate two novel CN-substituted two-dimensional sp²-carbon-linked conjugated polymers (2D CCPs) containing a chromophore triphenylene unit. The Knoevenagel polymerization between 2,3,6,7,10,11-hexakis(4-formylphenyl)triphenylene (HFPTP) and 1,4-phenylenediacetonitrile (PDAN) or 2,2’-(biphenyl-4,4’-diyl)diacetonitrile (BDAN), provides the crystalline 2D CCP-HFPTP-PDAN (2D CCP-1) and 2D CCP-HFPTP-BDAN (2D CCP-2) with dual pore structures, respectively. 2D CCP-1 and 2D CCP-2 exhibit the photoluminescence quantum yield (PLQY) up to 24.9% and 32.3%, which are the highest values among the reported 2D conjugated polymers and π-conjugated 2D covalent organic frameworks. Furthermore, compared with the well-known emissive small molecule tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), both 2D CCPs show superior photostability under UV irradiation for two hours, profiting from the twisted and rigid structures of the CN-substituted vinylene linkages. The present work will trigger the further explorations of novel organic emitters embedded in 2D CCPs with high PLQY and photostability, which can be useful for optoelectronic devices.

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Sisk, David Theodore. "I. Tunable Luminescence in Dendronized Poly(phenyleneethynylene)s Through Post-Polymerization Chemical Modification II. Rigid, Helical Polymers Based Upon Chiral Hydrobenzoin." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194768.

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Dendritic encapsulation of poly(phenyleneethynylene)s or PPEs has been shown to enhance photoluminescent quantum efficiency and facilitate energy transfer by funneling photonic energy absorbed on the dendron periphery efficiently to the conjugated polymeric core. The research presented herein focuses on incorporating degradable dendron onto PPEs, examining whether or not similar benefits were conferred upon the proposed system and controlling polymer luminescence through the elimination of the insulating macromolecules. PPEs appended with disassembling dendrons of various generation sizes were synthesized and their optical properties studied. Polymer luminescence was then quenched via chemical degradation of the disassembling dendrons. Furthermore, the macromolecules resulting from disassembly exhibited tunable luminescence properties upon manipulation of pH. Consequently, it was determined that polymer luminescence could be controlled upon forming phenolic moieties along the PPE backbone. Tunable emission was later realized in the thin film as well through the integration of crosslinkable dendrons onto the polymer core.Recently, helical synthetic linear polymers have demonstrated the ability to facilitate stereoselective processes such as catalysis, recognition and separation. Consequently, it has become increasingly desirable to develop new platforms capable of imparting asymmetry. The work presented herein describes the synthesis of a series of polymers based upon chiral hydrobenzoin and the subsequent conformational analysis performed on these materials. It was envisioned that these polymeric materials might inherently possess conformational asymmetry and as result could be able to impart configurationally chirality by introducing a diastereomeric bias for the formation of one enantiomer over the other during the course of the reaction.

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Kimyonok, Alpay. "Side-chain functionalized luminescent polymers for organic light-emitting diode applications." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/29649.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009. Committee Chair: Weck, Marcus; Committee Member: Christopher Jones; Committee Member: Jean-Luc Bredas; Committee Member: Joseph Perry; Committee Member: Laren M. Tolbert. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Stay, David, and David Stay. "Design, Synthesis, and Characterization of Ionically Functionalized Conjugated Polymers with Varying Ion Density and Type." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12326.

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Phenylene-based conjugated polymers are of interest for their fascinating electronic and optical properties. The introduction of bound ions into these materials adds great versatility because it can affect solubility, aggregation properties, doping chemistry, luminescence, and response to electrical stimuli. Despite ionic density being a central materials parameter in ionically functionalized conjugated polymers (IFCPs), it has been explored only in limited ranges. The primary advance reported in this dissertation is the development of three complementary synthetic routes to anionic and cationic poly(fluorene)s where the density of ionic functional groups was systematically varied between 0.05 and 0.5 per phenylene unit. There have been very few reports of IFCPs in this range. The three routes all use the Suzuki polycondensation reaction (SPR) to form poly[(R-fluorene)-co-alt-(R'-fluorene)] (PFF) IFCPs, and they differ from one another in when ionic functionality is introduced to the polymer. The development of these approaches grew out of studies on the SPR as it applies to ionically functionalized monomers, specifically, complications created by the two-phase nature of typical Suzuki couplings. In the first route, ions are added to the monomer and directly polymerized into the polymer using a single-phase SPR made possible by using oligoether functionality and a judiciously chosen solvent system. This route was used in the synthesis of a family of sulfonate and oligoether containing PFFs. In the second and third routes, ionic functionality is added after the polymer is formed either in solution or in solid films, respectively. The use of all nonionic monomers during the SPR avoided the complications encountered with two-phase reactions involving ionic monomers. The precursor polymers synthesized for these routes included a family of hexyl and bromohexyl containing PFFs and a family of oligoether and bromohexyl containing PFFs. The former were used to demonstrate post-polymerization quaternization to form cationic PFFs in solid films, and the later were quaternized in solution to yield soluble cationic PFFs. All of the polymers had very similar optical properties with the wavelengths of maximum absorption and emission in the range of 370-385 and 416-425 nm, respectively, and molecular weights greater than 10kDa and exhibited both positive and negative solvatofluorchromism due to aggregation phenomena.

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Pinaud, Florent. "Etude des propriétés interfaciales et luminescentes de microgels stimulables." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0096/document.

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Les microgels sont des particules colloïdales de polymère réticulé gonflées par un solvant. Déformables et poreuses, elles peuvent changer d’état de gonflement lors de l’application d’un stimulus. Ce travail de thèse a pour but de développer de nouveaux concepts tirant profit des propriétés stimulables et de la déformabilité intrinsèque des microgels tout en approfondissant les connaissances sur le comportement de ces objets en solution et aux interfaces. Les microgels de poly(N-alkylacrylamide) sont utilisés comme modèles. Dans un premier temps, notre travail a porté sur l’étude d’un nouveau type de microgels électrochimiluminescents grâce à l’incorporation d’un complexe métallique de ruthénium dans la matrice polymère. A la transition de phase, ces microgels présentent une exaltation de l’intensité ECL jusqu’à 2 ordres de grandeur, en lien avec la distance entre les sites redox. Le concept est ensuite transposé à des microgels sensibles aux saccharides et à des systèmes comportant deux luminophores, un donneur ECL et un accepteur d’énergie pouvant donner lieu à un transfert d’énergie par résonance. La deuxième partie de la thèse est consacrée à l’adsorption de microgels à une interface liquide-liquide plane, en vue de mieux comprendre l’origine de la stabilité des émulsions stabilisées par ce genre d’objets. De façon analogue aux protéines flexibles, les microgels changent de conformation à l’interface, passant d’un état étendu à un état comprimé, à l’origine de variations de l’élasticité interfaciale. Les microgels ainsi adsorbés sont fonctionnalisés de façon régiosélective dans l’eau et permettent de produire des microgels non symétriques, dits Janus, susceptibles de s’auto-assembler Microgels are colloidal particles made of cross-linked polymer swollen by a solvent. Soft and porous, they can adapt their swelling degree in response to a stimulus. The main objective of this work is to develop new concepts taking advantage of microgels’ stimuli-responsive properties and intrinsicsoftness while deepening understanding of their properties in solution and at interfaces. Poly(Nalkylacrylamide) microgels are used as a model. Initially our work focused on the study of a new type of electrochemiluminescent (ECL) microgels thanks to the incorporation of a ruthenium complex in the polymer matrix. At the volume phase transition, these microgels exhibit an amplification of the ECL intensity up to 2 orders of magnitude, related to the decrease of the distance between redox sites. This concept is then transposed to saccharides-sensitive microgels and systems bearing two luminophores, an ECL donor and an energy acceptor in order to give rise to resonance energy transfer. The second part of this manuscript is devoted to adsorption of microgels at a planar liquid-liquid interface, to improve knowledge on the origin of the stability of emulsions stabilized by such objects. Such as flexible proteins, microgels can change their conformation at the interface, from an extended to a compressed state, causing variation in the interfacial elasticity. When microgels are adsorbed they can also be functionalized regioselectively in water to produce non-symmetrical microgels, called Janus, able to self-assemble

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Marchini, Leonardo Guedes. "Desenvolvimento de marcador óptico para processamento de poliolefinas." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-29052013-081024/.

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Pesquisas e publicações sobre polímeros luminescentes vêm sendo desenvolvidas nos últimos anos devido à inovação acadêmica, porém ainda no âmbito nacional possuem aplicação industrial limitada. Marcadores ópticos processados são pouco explorados devido à dificuldade de processamento dos materiais poliméricos luminescentes com estabilidade de luminescência. Os materiais utilizados para o processamento de polipropileno luminescente foram Poliamida 6 (PA6) dopada com complexo sintetizado de [Eu(tta)3(H2O)2] obtida através do processo de diluição do polímero e técnica de derramamento. As poliolefinas, por serem inertes, não se adequam ao procedimento comum de dopagem, assim no presente trabalho, o polipropileno luminescente foi preparado indiretamente por dopagem com poliamida dopada com complexo de európio em processamento por extrusão. As técnicas de caracterização utilizadas foram a Análise Térmica (TG), Calorimetria Exploratória Diferencial (DSC), Difração de Raios-X (XRD), Espectroscopia de infravermelho (FT-IR) e estudo das propriedades fotoluminescentes. A blenda PP/PA6:Eu(tta)3 processada apresentou propriedades luminescentes observadas nas transições intraconfiguracionais de bandas finas 4f6 - 4f6 relativas aos níveis de excitação de energia 7F0 → 5L6 (394nm), 7F0 → 5D3 (415nm), 7F0 → 5D2 (464nm), 7F0 → 5D1 (525nm) e 7F0 → 5D0 (578nm). Tanto a blenda de PP/PA6:Eu(tta)3 e os filmes de PA6:Eu(tta)3 quando expostos a luz UV (365nm) apresentaram luminescência vermelha. Os resultados de TG mostraram que sob atmosfera de O2 o PP dopado PA6:Eu(tta)3 apresentou maior estabilidade do que o PP puro. Neste trabalho foi possível processar PP/PA6:Eu(tta)3 com propriedades térmicas e fotoestabilidade, que permitem sua utilização com marcador óptico em processamentos. Research and publications about luminescent polymers have been developed in the last years for the academic innovation; however the industrial application has been very limited in this area. Processed Optical markers are few explored due to the difficult to process luminescent polymeric materials with stable luminescence. The materials used of processing luminescent polypropylene (PP) were polyamide 6 (PA6) doped with europium complex [Eu(tta)3(H2O)2] obtained through the dilution and casting process. Due to their inercy, polyolefins do not fit into the common procedure of doping, in consequence, in this work luminescent polypropylene was indirectly prepared by polyamide 6 doped with europium complex through extrusion process. Product characterization was done using Thermalgravimetry analysis (TG), Differential Scanning Calorimetric (DSC), X-Ray Diffraction (XRD), Infrared spectroscopy (FTIR) and fotoluminescence of emission and excitation. The blend PP/PA6:Eu(tta)3 presented luminescent properties, after semi-industrial process, as observed in the narrow bands of intraconfiguration transitions - 4f6 relatives to energy levels 7F0 → 5L6 (394nm), 7F0 → 5D3 (415nm), 7F0 → 5D2 (464nm), 7F0 → 5D1 (525nm) e 7F0 → 5D0 (578nm) of emission spectrum. Red light of the pellets or film is emitted when excited in UV lamp (365nm). TG results showed under O2 atmosphere that PP doped with PA6:Eu(tta)3 was more stable than pure PP. In this work luminescent PP/PA6:Eu(tta)3 was processed with properties of thermal and photo stability which can be used as optical marker in polymer processing.

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Maia, Francisco Carlos Barbosa. "Correlação entre polarização da luminescência e orientação molecular em polímeros conjugados." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-13112007-145818/.

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Nesta dissertação, visamos o entendimento de processos intermediários que regem a transferência de energia e determinam as propriedades ópticas de polímeros conjugados, a fim de encontrar meios para aumentar a eficiência de emissão e o tempo de vida dos ?LED?s? orgânicos. Estudamos especificamente o polímero PPV, poli(p-fenileno vinilideno), sintetizado através de novo método desenvolvido no Grupo de Polímeros do Instituto de Física de São Carlos, por Marletta e colaboradores[1], na forma de filmes finos depositados pelas técnicas ?spincast? e de automontagem (LbL). Para o trabalho utilizamos técnicas espectroscópicas de luminescência, excitação seletiva e absorbância. Por meio de técnicas de engenharia molecular e através do ordenamento induzido da rede polimérica, avaliamos o peso que têm os eventos intermediários à emissão. Estiramos gradualmente filmes de PTHT/PPV depositados sobre Teflon, sob um eixo preferencial, e constatamos a dependência da polarização da luz emitida com processos de transferência de energia e com a anisotropia da matriz polimérica. Realizamos a separação das cadeias do copolímero a fim de analisar separadamente a transferência de energia entre os segmentos conjugados pertencentes a cadeias distintas (processos intercadeia) ou ao longo da cadeia (processos intracadeia). Esta separação intercadeia e intracadeia resultaram em um significativo aumento da eficiência da emissão, assim como um deslocamento da banda de emissão para o azul, privilegiando a emissão de segmentos de menor conjugação e que participavam apenas nos processos de relaxação de energia e transferência da excitação e não dos estados emissivos finais. Separamos os segmentos conjugados dentro da própria cadeia do copolímero, regulando o comprimento de conjugação, através da incorporação de DBS. Aqui, verificamos, os processos de transferência intracadeia concorrem em igual peso com processos intracadeia na migração energética em polímeros conjugados. Concluímos que o processo limitante da eficiência de emissão em polímeros conjugados e dispositivos é a eficiente transferência de energia entre cadeias ou ao longo da cadeia para centros supressores de energia. The main goal of this work is the understanding of intermediated energy relaxation processes that are governed by Energy Transfer. Such processes strongly affect the optical properties of conjugated polymers, reducing the emission efficiency and the life time of OLEDs. We study specifically the polymer poly(p-phenylene vinylene), PPV, synthesized through the new method developed by Marletta and co-workers [1]. The films were prepared by Spincast and self-assembly (Layer-by-Layer) techniques on different substrates. The optical characterization of the polymeric material was carried out by photoluminescence, selective excitation spectroscopy and UV-Vis absorbance measurements. With the use of molecular engineering techniques and by changing the polymeric order induced by uniaxial stretch of the films deposited on a flexible substrate, it was possible to infer the weight of intermediary events in final emission process. A special issue of this work was the study of the optical properties of thin PPV films deposited on flexible Teflon substrates under very low deformation levels. Optical data of low stretched conjugated polymers on transparent substrates were not previously available in the literature. Continuous axial stretch was applied at room temperature to very thin PPV films enabling simultaneous luminescence and absorbance polarization measurements. The optical properties of polymeric light emitting devices are strongly dependent on the structural order of the polymer chains and the energy transport mechanism between the conjugated segments. We demonstrate that such low stretched films presents a very efficient isotropic-to-polarized conversion regarding the fact we are dealing with energy transfer between luminescent chromophore of same species. We also carried out chain separation of conjugated segments of a PPV copolymer in order to analyze two Energy Transfer kinds: one that occurs among PPV segments in different chains (interchain processes) and the other involving the Energy Transfer between PPV segments along the same PPV chain (intrachain processes). To account for the interchain separation of the PPV segments we diluted the PPV chain in an inert polymeric matrix. The novelty, however, lies in the precise control of the separation of PPV segments along the chain by using a copolymer with sequences of conjugated PPV and non-conjugated PTHT distributed randomly along the polymer chain. The efficiency increase together with the spectral blue shif with the segment separation show that inter- and intrachain exciton mobility is enhanced by low range Förster Energy Transfer. For the case of samples without chain separation, it is easier for excitons to move around by energy transfer process and find quenching defects before their radioactive decay. For diluted or low conjugated samples, excitons will not reach defects before recombination since Energy Transfer is suppressed. Thus, we verify, the Intrachain Energy Transfer process have the same influence as for Interchain process produced by the energy migration among conjugated polymers segments. From a more fundamental point of view, the establishment of a controlled ordering and separation of the polymeric chains may reduce effects such as the luminescence quenching that strongly reduce the emission efficiency in organic devices.

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Raies, Ahlem. "Elaboration de films minces électroluminescents à base de polymère conducteur électronique et de nanotubes de carbone." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLC011/document.

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Le sujet de cette thèse se situe dans le contexte de l'électronique organique à base de polymères conjugués et de nanotubes de carbone. Nous avons choisi la famille des polyfluorènes principalement en raison de leur émission dans le bleu, leur bon rendement quantique ainsi que pour la facilité avec laquelle on peut modifier leurs propriétés en greffant différents groupements fonctionnels sur la structure de base du fluorène. L'originalité des recherches effectuées au laboratoire concerne la structure des films électroluminescents que nous réalisons. Leur principe de fonctionnement repose sur l'utilisation de nanotubes de carbone en tant que film support pour le dépôt du polymère. Le travail réalisé au cours de cette thèse a principalement consisté à élaborer des films de polymères avec des épaisseurs et des taux de dopage contrôlés à la surface des nanotubes de carbone en optimisant les divers paramètres de synthèse électrochimique. Nous avons également utilisé des groupements fonctionnels pour améliorer les performances du polyfluorène et augmenter la compatibilité entre les couches polymère/nanotubes de carbone. Dans cette optique, nous avons mis en œuvre l'utilisation de différents outils pour la caractérisation des propriétés des films. Les propriétés intrinsèques des nanotubes de carbone ont donc pour effet de doper le polymère et d'améliorer le transport des charges au sein des couches tout en maintenant les performances de luminescence dans le bleu des polyfluorènes The subject of this thesis lies in the context of organic electronic based on conjugated polymers. We have chosen the class of polyfluorene mainly because of their blue emission, good quantum efficiency and possibility of modifying their properties by grafting side chain groups. The originality of our research relies upon the use of a particular devices structure. The structure of our electroluminescent films is based on the use of a thin layer of carbon nanotubes added to the structure of the emissive layer without involving any chemical modification.The work done in this thesis has mainly consisted of deposing polymer films with thicknesses and doping level controlled on the surface of carbon nanotubes by optimizing various parameters of the electrochemical synthesis. Functional groups have also been grafted on the side of chains in order to improve the performances of the polymer and to increase the compatibility between the polymer layer and the carbon nanotube dispersion. The use of carbon nanotubes should improve the charge carriers whitout quenching the photophysical properties of the polymers

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Fischer, Christoph Siegfried Winfried [Verfasser]. "Luminescent Conjugated Polymer Nanoparticles from Suzuki-Miyaura Chain-Growth Polymerization / Christoph Siegfried Winfried Fischer." Konstanz : Bibliothek der Universität Konstanz, 2015. http://d-nb.info/1105479110/34.

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Feazell, Rodney P. Klausmeyer Kevin Kenneth. "Luminescent supramolecular silver(I) coordination complexes of pyridyl-substituted phosphinites, phosphonites and amines." Waco, Tex. : Baylor University, 2005. http://hdl.handle.net/2104/3009.

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Dissertations / Theses on the topic 'Polymer luminescence'

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