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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

HOW ELECTRODE MATERIAL AFFECTS THE PERFORMANCE OF POLYMER LIGHT-EMITTING ELECTROCHEMICAL CELLS

Hohertz, DONNA 23 September 2008 (has links)
Polymer light emitting electrochemical cells (LECs) are solid-state devices containing an active layer blend of luminescent polymer, ion transport material and salt sandwiched between two electrodes. They operate on the principal of in situ electrochemical doping. Doping entails the injection of electronic charge from the electrodes, causing the reduction/oxidization of the luminescent polymer, and accompanied by charge compensation through the redistribution of salt counter-ions. Due to the high conductivity of the doped polymer, a fully turned on LEC has a dramatically reduced contact and bulk resistance. This gives the LEC certain intrinsic advantages such as balanced charge injection, low operating voltage and high quantum efficiencies, even when stable metal or symmetric electrodes are used. These properties have led to the popular assumption that the electrode work function is not a critical device parameter for LEC operation. In this thesis, I describe my original research to determine how the electrode composition influences LEC performance. A series of sandwich and planar configuration LECs with various electrodes on identical MEH-PPV (poly[5-(2-ethylhexyloxy)-2-methoxy-1,4-phenylene vinylene]):PEO (poly ethylene oxide):LiTr (Lithium trifluoromethanesulfonate) based films are constructed. I demonstrate that the doping profile, doping propagation speed, emission zone shape, emission zone location, electro-luminescence (EL) turn-on, and EL efficiency are all strongly affected by the choice of electrode materials. LECs with asymmetrical electrodes optimized for both electron and hole injection result in the best overall performance. Using an optimized electrode configuration, I am able to realize extremely large crown ether based planar LECs. MEH-PPV: dicyclohexano-18-crown-6 (DCH18Cr6): LiTr and 108GE:DCH18Cr6:LiTr devices with various symmetric and asymmetric electrode configurations were constructed, where 108GE is the fluorene copolymer poly[(9,9-dioctyl-2,7-divinylene-fluorenylene)-alt-co-(2-methoxy-5-(ethylhexyloxy)-1,4-phenylene)]. I demonstrate ii i and image the first ever crown ether-based planar LECs with millimeter inter-electrode spacing. Due to minimal phase separation, crown ether-based LECs display highly uniform doping propagation and very smooth emission zones. Junction relaxation, de-doping and reverse bias operation experiments are also presented, and results compared to behavior in PEO based LECs. Additionally, I demonstrate that crown ether-based LECs do not exhibit frozen junction behavior at room temperature. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2008-09-23 16:15:06.569
2

Creating novel thermally activated delayed fluorescence (TADF) emitters for light-emitting electrochemical cells (LEECs) and organic light-emitting diodes (OLEDs) applications and their structure-property relationship

Wong, Michael Yin January 2017 (has links)
Developing organic light-emitting diodes (OLEDs) as the next generation display devices is not only of industrial interest, but also a scientific challenge in and of itself that requires multi-disciplinary efforts to make the technology successful. Thermally activated delayed fluorescence (TADF) is a recent breakthrough in OLED technology whose prime value is to enable purely organic emitters to recruit the dark triplet excitons in the device, thus avoiding expensive and toxic rare metal based emitters. This thesis is centred on TADF and contains work in three major areas. Firstly, novel ionic TADF emitters were designed for use in light-emitting electrochemical cells (LEECs), which is an alternative electroluminescent device technology to OLEDs, with a much simplified fabrication procedure and architecture. The vast majority of these ionic emitters are based on reported TADF scaffolds where the donors were tethered with an imidazolium hexafluorophosphate group to obtain the ionic character required for LEEC devices (TL and BTL series, Chapter 2). On the other hand, TADF emitters with a carboxylate group were also designed which act as both acceptor and intrinsic charged functionality for LEEC applications (CTL series, Chapter 2). Secondly, attempts were made to create novel TADF molecular scaffolds in order to enrich the current library of TADF emitters. Research efforts were focused on polyaromatic moieties such as anthracene (An series, Chapter 4) and fluoranthene (FA series, Chapter 4) that are seldom reported in TADF literature. In addition, TADF emitters with phosphine oxide as the acceptor group have also been studied (PO series, Chapter 5). Lastly, structure-property relationship studies of TADF emitters were undertaken as a function of tuning of donor and acceptor functionalities using both theoretical and experimental approaches in order to gain more insight for designing desirable TADF emitters (Chapter 3).
3

Scanning Photocurrent and Photoluminescence Imaging of Frozen Polymer Light Emitting Electrochemical Cells

Inayeh, Alex 29 May 2013 (has links)
A polymer light-emitting electrochemical cell (LEC) is a solid-state polymer device operating according to in situ electrochemical doping and the formation of a light-emitting polymer p-n junction. This operating mechanism, however, has been the subject of much debate. Planar LECs with millimeter scale interelectrode spacings offer great advantages for directly observing the electrochemical doping process. Photoluminescence quenching and the formation of a light-emitting junction have been observed in planar polymer LECs, demonstrating the existence of electrochemical doping. The chemical potential difference between the p- and n-doped regions creates a built-in potential/electric field in the junction region, which can be probed by measuring the optical beam induced current (OBIC). This study utilizes a versatile and easy-to-use method of performing OBIC analysis. The OBIC and photoluminescence profiles of LECs have been simultaneously measured by scanning a focused light beam across large planar LECs that have been turned on and cooled to freeze the doping profile. The photoluminescence intensity undergoes a sharp transition between the p- and n-doped regions. The OBIC photocurrent is only observed in the transition region that is narrower than the width of the excitation beam, which is about 35 μm. The results depict a static planar polymer p-n junction with a built-in electric field pointing from n to p. The electrode interfaces do not produce a measurable photocurrent indicating ohmic contact. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-05-28 12:52:14.171
4

Caracterização de células eletroquímicas emissoras de luz: propriedades elétricas, estrutura e morfologia / Characterization of light emitting electrochemical cells: electrical properties, structure and morphology

Torres, Bruno Bassi Millan 08 December 2017 (has links)
As células eletroquímicas emissoras de luz são dispositivos eletroluminescentes cuja camada ativa é uma mistura de um material eletroluminescente e um eletrólito sólido a base de sais de metais alcalinos, geralmente lítio. A presença dos íons na camada ativa modificam o mecanismo de funcionamento das células quando comparadas ao diodos emissores de luz. Nas células, a concentração de íons nas interfaces eletródicas forma uma dupla camada elétrica que auxilia a injeção de cargas na camada ativa, por sua vez e na presença dos íons, o material eletroluminescente sofre dopagem se tornando condutor, os portadores injetados irão se encontrar numa região da camada ativa recombinando-se e emitindo luz. Compreender as interações dos diversos materiais que formam a camada ativa é fundamental para otimizar o desempenho do dispositivo. Neste trabalho estudamos a interação do ADS108GE, um polímero luminescente, e um eletrólito sólido a base de poli (óxido de etileno) (PEO) e LiCF3SO3 ou LiB(C2O4)2. O LiB(C2O4)2 foi sintetizado neste trabalho para estudar a viabilidade de se substituir o LiCF3SO3 que é o sal tipicamente utilizado nas células. Foram utilizadas técnicas de Análise Dinâmico-Mecânica (DMA), Espectroscopia Vibracional no Infravermelho (FTIR), Microscopia de Força Atômica (AFM), Difração de Raios-X (DRX), Microscopia Óptica de Varredura no Campo Próximo (IR-SNOM), Impedância Elétrica e Voltametria Cíclica. Os resultados de DMA em conjunto com DRX e AFM, permitiram estabelecer que o aumento da concentração de sal contribui para mudanças morfológicas que se relacionam com o aumento da fração de fase amorfa e independem do ânion, demonstrando que estes efeitos estão ligados à interação PEO-Lítio. Por outro lado, os espectros de FTIR e resultados de impedância elétrica mostram que o aumento da concentração de LiCF3SO3 gera agregação do sal diminuindo a condutividade, a mobilidade iônica e o número de portadores efetivos, enquanto para o LiB(C2O4)2 não se observa tal efeito. O IR-SNOM permitiu identificar nas misturas utilizadas como camada ativa que o ADS108GE forma estruturas globulares embebidas numa matriz de PEO. Do ponto de vista operacional, as células a base de LiB(C2O4)2 possuem uma eficiência maior do que as a base LiCF3SO3 e maior estabilidade. / Light-emitting electrochemical cells are electroluminescent devices whose active layer is a mixture of an electroluminescent material and a solid electrolyte based on alkaline salts, usually a lithium salt. The ions within thea ctive layer change the devices working mechanism when compared to light emitting diodes. In the cells, there is an ion build up at electrodic interfaces creating an electric double layer allowing charge injection in the active layer. The electroluminescent material is doped by these injected charges becoming conductive. These injected charges recombine emitting light. In order to optimize devices performance, it is fundamental to study materials interactions when mixed as an active layer. In this work, we studied the interactions between ADS108GE, a luminescent polymer, and a solid electrolyte based on polyethylene oxide and LiCF3SO3 or LiB(C2O4)2. LiB(C2O4)2 was prepared in this work to assess its feasibility as LiCF3SO3 substitution which is the typical choice. We used the following techniques in this work: Dynamical Mechanical Analysis (DMA), Infrared Vibration Spectroscopy (FTIR), Atomic Force Microscopy AFM), X-Ray Diffraction (XRD), Infrared Scanning Near-Field Optical Microscopy (IRSNOM), Electrical Impedance and Cyclic Voltammetry. From DMA, XRD and AFM results, it is possible to conclude that as we increase salt concentration, the active layer has morphological changes related to an increasing fraction of an amorphous phase. These effects are anion independent showing that PEO-Li interactions are the responsible ones. On the other hand, FITR and electrical impedance experiments show that increasing LiCF3SO3 concentration leads to salt aggregation decreasing conductivity, ionic mobility and the effective number of carriers, moreover, we do not see this effect with LiB(C2O4)2. IR-SNOM identified that ADS108GE were organized as globular structures embedded in a PEO matrix. The cells made with LiB(C2O4)2 were more efficient than those based on LiCF3SO3 and were even more stable.
5

In Quest of Printed Electrodes for Light-emitting Electrochemical Cells: A Comparative Study between Two Silver Inks

Nahid, Masrur Morshed January 2012 (has links)
This thesis presents a comparative study between two silver nanoparticle inks that were deposited using a Drop-on-Demand (DoD) inkjet printer, aiming at finding a functional ink that can be used to print electrodes in Light-emitting Electrochemical Cells (LECs). To achieve this, a DoD inkjet printer was installed and an acquaintance with the printer was attained. Among the two inks, one was employed as received while the other was reformulated, and successful deposition of both the inks was observed. During the reformulation process, it was seen that the highly volatile tetrahydrofuran (THF) solvent can be used to improve the ink properties, in contrast to what is recommended. After that, the inks were deposited on UV-ozone treated glass substrates, sintered at an elevated temperature under ambient conditions, and their specific resistances and thicknesses were measured. Finally, the inks were used to print the anode in a structured sandwich-cell LEC. The performance comparison was conducted by observing the emitted light of the LECs. The results indicate that the reformulated ink performs better, probably due to the lower silver concentration that results in flatter surface, which in turn effectively alleviates shorts.
6

Scaling and Optimization of Polymer Bulk Homojunction Light-Emitting and Photovoltaic Cells

Bonnet, Wayne 15 September 2008 (has links)
The polymer light-emitting electrochemical cell (LEC) is an alternative method for producing electroluminescence (EL) from conjugated luminescent polymers. The in situ electrochemical doping process that leads to a dynamic p-n junction makes the devices highly insensitive to device thickness and relatively insensitive to electrode materials. These characteristics make an extremely large planar configuration accessible for observing the cross-section of the device and watching it turn on dynamically. By cooling the device to freeze ionic motion, the junction can be stabilized and photovoltaic (PV) characteristics investigated. In the planar configuration, the p-n junction was found to make up a small fraction of the inter-electrode spacing. Enabled by the insensitivity to electrode materials, small metallic particles embedded in the LEC film led to a large number of p-n junctions that could be turned on in series and parallel. This alleviates the issue of low specific emitting area suffered by planar devices and leads to improved EL effciency as well as a high open circuit voltage (Voc) when operated as a PV cell. The bulk homojunction fabrication process has been optimized by segregating the metallic particles to eliminate large aggregates. A new technique to achieve highly uniform EL from large planar LECs is also presented here. By the evaporation of a thin gold or silver film on top of an LEC, independent islands form that act as doping initiation sites across the device width. A bulk homojunction is turned on in the top layer of the LEC with a high applied bias. Island diameters and spacings are several orders of magnitude smaller than the particles in previously-reported bulk homojunction devices. Both island and particle devices had their interelectrode spacings scaled down by at least a factor of 10. The successful scaling is a promising result for the possibility of a sandwich configuration bulk homojunction device. In the case of silver island devices, cooling a 50-micron wide device after turn-on resulted in a PV cell with an open circuit voltage of 8.3 V, several times the band gap of the luminescent polymer used. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2008-09-12 12:21:12.949
7

Functional and Flexible Light-Emitting Electrochemical Cells

Asadpoordarvish, Amir January 2015 (has links)
The introduction of artificial illumination has brought extensive benefits to mankind, and during the last years we have seen a tremendous progress in this field with the introduction of the energy-efficient light-emitting diode (LED) and the high-contrast organic LED display. These high-end technologies are, however, produced using costly and complex processes, and it is anticipated that the next big thing in the field will be the advent of a low-cost and “green” illumination technology, which can be fabricated in a cost- and material-efficient manner using non-toxic and abundant raw materials, and which features attractive form factors such as flexibility, robustness and light-weight. The light-emitting electrochemical cell (LEC) is a newly invented illumination technology, and in this thesis we present results that imply that it can turn the above vision into reality. The thin-film LEC comprises an active material sandwiched between a cathode and an anode as its key constituent parts. With the aid of a handheld air-brush, we show that functional large-area LECs can be fabricated by simply spraying three layers of solution -- forming the anode, active material, and cathode -- on top of a substrate. We also demonstrate that such “spray-sintered” LECs can feature multicolored emission patterns, and be fabricated directly on complex-shaped surfaces, with one notable example being the realization of a light-emission fork! Almost all LECs up-to-date have been fabricated on glass substrates, but for a flexible and light-weight emissive device, it is obviously relevant to identify more appropriate substrate materials. For this end, we show that it is possible to spray-coat the entire LEC directly on conventional copy paper, and that such paper-LECs feature uniform light-emission even under heavy bending and flexing. We have further looked into the fundamental aspects of the LEC operation and demonstrated that the in-situ doping formation, which is a characteristic and heralded feature of LECs, can bring problems in the form of doping-induced self-absorption. By quantitatively analyzing this phenomenon, we provided straightforward guidelines on how future efficiency-optimized LEC devices should be designed. The in-situ doping formation process brings the important advantage that LECs can be fabricated from solely air-stabile materials, but during light emission the device needs to be protected from the ambient air. We have therefore developed a functional glass/epoxy encapsulation procedure for the attainment of LEC devices that feature a record-long ambient-air operational lifetime of 5600 h. For the light-emission device of the future, it is however critical that the encapsulation is flexible, and in our last study, we show that the use of multi-layer barrier can result in high-performance flexible LECs.
8

Caracterização de células eletroquímicas emissoras de luz: propriedades elétricas, estrutura e morfologia / Characterization of light emitting electrochemical cells: electrical properties, structure and morphology

Bruno Bassi Millan Torres 08 December 2017 (has links)
As células eletroquímicas emissoras de luz são dispositivos eletroluminescentes cuja camada ativa é uma mistura de um material eletroluminescente e um eletrólito sólido a base de sais de metais alcalinos, geralmente lítio. A presença dos íons na camada ativa modificam o mecanismo de funcionamento das células quando comparadas ao diodos emissores de luz. Nas células, a concentração de íons nas interfaces eletródicas forma uma dupla camada elétrica que auxilia a injeção de cargas na camada ativa, por sua vez e na presença dos íons, o material eletroluminescente sofre dopagem se tornando condutor, os portadores injetados irão se encontrar numa região da camada ativa recombinando-se e emitindo luz. Compreender as interações dos diversos materiais que formam a camada ativa é fundamental para otimizar o desempenho do dispositivo. Neste trabalho estudamos a interação do ADS108GE, um polímero luminescente, e um eletrólito sólido a base de poli (óxido de etileno) (PEO) e LiCF3SO3 ou LiB(C2O4)2. O LiB(C2O4)2 foi sintetizado neste trabalho para estudar a viabilidade de se substituir o LiCF3SO3 que é o sal tipicamente utilizado nas células. Foram utilizadas técnicas de Análise Dinâmico-Mecânica (DMA), Espectroscopia Vibracional no Infravermelho (FTIR), Microscopia de Força Atômica (AFM), Difração de Raios-X (DRX), Microscopia Óptica de Varredura no Campo Próximo (IR-SNOM), Impedância Elétrica e Voltametria Cíclica. Os resultados de DMA em conjunto com DRX e AFM, permitiram estabelecer que o aumento da concentração de sal contribui para mudanças morfológicas que se relacionam com o aumento da fração de fase amorfa e independem do ânion, demonstrando que estes efeitos estão ligados à interação PEO-Lítio. Por outro lado, os espectros de FTIR e resultados de impedância elétrica mostram que o aumento da concentração de LiCF3SO3 gera agregação do sal diminuindo a condutividade, a mobilidade iônica e o número de portadores efetivos, enquanto para o LiB(C2O4)2 não se observa tal efeito. O IR-SNOM permitiu identificar nas misturas utilizadas como camada ativa que o ADS108GE forma estruturas globulares embebidas numa matriz de PEO. Do ponto de vista operacional, as células a base de LiB(C2O4)2 possuem uma eficiência maior do que as a base LiCF3SO3 e maior estabilidade. / Light-emitting electrochemical cells are electroluminescent devices whose active layer is a mixture of an electroluminescent material and a solid electrolyte based on alkaline salts, usually a lithium salt. The ions within thea ctive layer change the devices working mechanism when compared to light emitting diodes. In the cells, there is an ion build up at electrodic interfaces creating an electric double layer allowing charge injection in the active layer. The electroluminescent material is doped by these injected charges becoming conductive. These injected charges recombine emitting light. In order to optimize devices performance, it is fundamental to study materials interactions when mixed as an active layer. In this work, we studied the interactions between ADS108GE, a luminescent polymer, and a solid electrolyte based on polyethylene oxide and LiCF3SO3 or LiB(C2O4)2. LiB(C2O4)2 was prepared in this work to assess its feasibility as LiCF3SO3 substitution which is the typical choice. We used the following techniques in this work: Dynamical Mechanical Analysis (DMA), Infrared Vibration Spectroscopy (FTIR), Atomic Force Microscopy AFM), X-Ray Diffraction (XRD), Infrared Scanning Near-Field Optical Microscopy (IRSNOM), Electrical Impedance and Cyclic Voltammetry. From DMA, XRD and AFM results, it is possible to conclude that as we increase salt concentration, the active layer has morphological changes related to an increasing fraction of an amorphous phase. These effects are anion independent showing that PEO-Li interactions are the responsible ones. On the other hand, FITR and electrical impedance experiments show that increasing LiCF3SO3 concentration leads to salt aggregation decreasing conductivity, ionic mobility and the effective number of carriers, moreover, we do not see this effect with LiB(C2O4)2. IR-SNOM identified that ADS108GE were organized as globular structures embedded in a PEO matrix. The cells made with LiB(C2O4)2 were more efficient than those based on LiCF3SO3 and were even more stable.
9

Fabricação e caracterização de células eletroquímicas emissoras de luz (LECs)

Dias, Rodrigo Coura 24 November 2017 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-09T14:16:49Z No. of bitstreams: 1 rodrigocouradias.pdf: 2508131 bytes, checksum: a85f5360d98ae17dab9812e3e61a46cd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-01-23T11:19:39Z (GMT) No. of bitstreams: 1 rodrigocouradias.pdf: 2508131 bytes, checksum: a85f5360d98ae17dab9812e3e61a46cd (MD5) / Made available in DSpace on 2018-01-23T11:19:39Z (GMT). No. of bitstreams: 1 rodrigocouradias.pdf: 2508131 bytes, checksum: a85f5360d98ae17dab9812e3e61a46cd (MD5) Previous issue date: 2017-11-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Um tipo de dispositivo que tem atraído atenção nos últimos anos no campo da Eletrônica Orgânica é as Células Eletroquímicas Emissoras de Luz, mais conhecidas como LECs (ou LEECs), do inglês Light Emitting Electrochemical Cells. Esses dispositivos eletrônicos têm baixa voltagem de operação, fabricação simples e barata, alto desempenho, ligeira independência dos materiais usados como eletrodo ou da espessura de suas camadas emissoras, além de terem a possibilidade de serem fabricados sobre substratos flexíveis. Por essas razões, as LECs têm sido usadas como possíveis substitutas para os já conhecidos OLEDs (Diodos Orgânicos Emissores de Luz), e o estudo de suas propriedades ópticas e elétricas e de seu princípio de funcionamento têm sido foco de trabalho de muitos cientistas. Dentre os modelos conhecidos que propõem descrever o funcionamento das LECs podemos citar três: a Teoria da Difusão, a Teoria da Dopagem Eletroquímica e a Teoria Mista. No primeiro a injeção de portadores na camada ativa seria facilitada pelos compostos iônicos presentes na blenda que a compõe, com posterior movimentação de cargas por difusão e recombinação no centro da camada. No segundo modelo ocorre a formação de três regiões dentro da blenda polimérica: uma região dopada do tipo p, uma região dopada do tipo n e uma camada isolante onde ocorre a recombinação de cargas para emissão de luz. A teoria mista assume que ambas são possíveis dependendo das condições em que se encontra o dispositivo. A fim de compreender como esses processos ocorrem e interferem no desempenho desses dispositivos propusemos diversas experiências alterando parâmetros importantes na sua fabricação. É proposto um modelo para a influência do tipo de cátion e ânion usado no sal presente na camada ativa e para descrever a influência da concentração desse sal na blenda polimérica que a compõe. Com base nas teorias descritas é colocada em evidência a influência da concentração de polímero transportador de íons na camada emissora e da espessura desta camada. Ao fim de todo o estudo obtivemos um dispositivo otimizado que é comparado com um dispositivo feito com um material novo sintetizado por colaboradores do departamento de Química da UFJF a fim de gerar expectativas para futuros trabalhos. / One type of device that has attracted attention in recent years in the field of Organic Electronics are the Light Emitting Electrochemical Cells, better known as LECs (or LEECs) These electronic devices have low operating voltage, simple and inexpensive manufacture, high-performance, light independence of the material used as electrode or the thickness of its emissive layer, besides having the possibility to be manufactured on flexible substrates. For these reasons the LECs have been used as possible substitutes for known OLEDs (Organic Light Emitting Diodes), and the study of their optical and electrical properties, and its operating principle have been working focus of many scientists. Among the known models proposed to describe the operation of LECs we can name three: the Theory of Diffusion, the Theory of Electrochemical Doping, and the Mixed Theory. In the first, injection of carriers in the active layer would be facilitated by the ionic compounds present in the blend that makes up, with subsequent movement of charges by diffusion and recombination in the center of the layer. In the second model happens the formation of three layers within the polymer blend: A p-type doped region, a n-type doped region and an insulating layer where recombination occurs for emitting light. Mixed theory assumes that both are possible depending on the conditions in which the device is. In order to understand how these processes occur and interfere with the performance of these devices we have proposed several experiments changing important parameters in its manufacture. A model is proposed for the influence of the type of cation and anion used in the salt present in the active layer, and to describe the influence of the concentration of this salt in the polymer blend that makes up. Based on the theories described it is put in evidence the influence of the concentration of the ion carrier polymer in the emitter layer and the thickness of this layer. After all the study we obtained an optimized device that is compared with a device made with a new material synthesized by employees from the Chemistry Department of UFJF to generate expectations for future work.
10

Développement de nouveaux complexes organométalliques de métaux de transition polyvalents pour la scintillation et la chimie médicinale / Development of new versatile organometallic complexes for scintillation and medicinal chemistry

Elie, Margaux 06 October 2017 (has links)
Deux nouvelles familles de complexes de cuivre(I) cationiques, de formules [Cu(NHC)(N^N)][X] et [Cu(P^P)(N^N)][PF6], ont été synthétisées avec des ligands 2,2’ bis pyridyl pontés, chélates à six chaînons, facilement modulables. Ces complexes présentent des émissions à l’état solide centrées entre 455 et 520 nm (bleu à vert), avec de larges décalages de Stokes et des rendements quantiques pouvant atteindre 0,86. De plus, l’émission via un phénomène de fluorescence retardée activée thermiquement (TADF) a été prouvée pour les complexes [Cu(NHC)(N^N)][X]. Les premiers scintillateurs plastiques dopés avec des complexes de cuivre(I) détectant les radiations nucléaires de type gammas ont été obtenus avec des complexes de formule générale [Cu(P^P)(N^N)][PF6]. Les complexes de formule [Cu(NHC)(N^N)][X] ont permis l’obtention des premières Cellules Electrochimiques Luminescentes (LECs) émettant dans le bleu et incorporant des complexes de cuivre(I). Enfin, les complexes de formule [Cu(NHC)(N^N)][X] à ligand 2,2’ dipyridylamine présentent une activité cytotoxique envers différentes lignées de cellules cancéreuses et apportent la possibilité d’une action ciblée sur les cellules tumorales via l’ajout d’un vecteur. La polyvalence de ces complexes de cuivre(I) repose sur les ligands 2,2’-bis-pyridyl pontés, chélates à six chaînons, dont la synthèse est facile d’accès et les propriétés électroniques et structurales sont modulables. / New cationic copper(I) complexes of general formula [Cu(NHC)(N^N)][X] and [Cu(P^P)(N^N)][PF6] were developed with 6-membered-ring 2,2’-bis-pyridyl derivatives as ligand. These complexes exhibited blue (420 nm) to green (520 nm) emissions in solid state, with large Stokes shifts and photoluminescence quantum yields up to 0.86. Furthermore, the emission of the [Cu(NHC)(N^N)][X] complexes via a thermally activated delayed fluorescence (TADF) was demonstrated. The first plastic scintillators incorporating copper(I) complexes and detecting gamma radiations were obtained with [Cu(P^P)(N^N)][PF6] complexes. Application of the [Cu(NHC)(N^N)][X] complexes to the LEC technology led to the first copper(I)-based blue emitting device. In the last chapter, we also demonstrated that copper(I) complexes [Cu(NHC)(N^N)][X] bearing a 2,2’-dipyridylamine as N^N ligand exhibited high cytotoxycity against different cancer cells lines. These complexes paved the way for the design of a new type of copper(I) anti-cancer agents with the opportunity to increase the selectivity against cancer cells via a vectorization of the N^N ligand. The versatility of these copper(I) complexes demonstrated in this work relied on the easy to handle and highly modular 2,2’-bis-pyridyl ligands.

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