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Suidong Wang - One of the best experts on this subject based on the ideXlab platform.
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saturated deep blue emitter based on a spiro benzoanthracene Fluorene linked phenanthrene Derivative for non doped organic light emitting diodes
2014Co-Authors: Houjie Liang, Xinxin Wang, Xingye Zhang, Zhiyang Liu, Xinhua Ouyang, Suidong WangAbstract:A spiro[benzoanthracene–Fluorene] Derivative containing a phenanthrene moiety, 2′,3-di(phenanthren-9-yl)spiro[benzo[de]anthracene-7,9′-Fluorene] (DPSBAF), was prepared by a Suzuki coupling reaction. The photophysical and photochemical properties were investigated systematically. A non-doped organic light-emitting diode using DPSBAF as the emitter achieved a luminance efficiency of 2.18 cd A−1 with Commission Internationale de l'Eclairage 1931 chromaticity coordinates of (0.15, 0.09). The synthesized spiro[benzoanthracene–Fluorene] Derivative with a high thermal stability, a glass transition temperature of 210 °C and a decomposition temperature of 410 °C, shows potential for application in non-doped saturated deep-blue organic light-emitting diodes.
Ahmet M Onal - One of the best experts on this subject based on the ideXlab platform.
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synthesis and electropolymerization of an ion sensing and fluorescent Fluorene Derivative bearing a quinoxaline moiety and its analogues with different donor units
2012Co-Authors: Arif Kivrak, Buket Bezgin Carbas, Metin Zora, Ahmet M OnalAbstract:Abstract A series of new Fluorene Derivatives bearing pendant quinoxaline moieties with different donor groups, namely 5′H-spiro[Fluorene-9,4′-pyrrolo[1,2-a]quinoxaline] (FQ), 2,7-di(thiophen-2-yl)-5′H-spiro[Fluorene-9,4′-pyrrolo[1,2-a]quinoxaline] (TQT), 2,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-5′H-spiro[Fluorene-9,4′-pyrrolo[1,2-a]quinoxaline] (EQE) and 2,7-bis(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-5′H-spiro[Fluorene-9,4′-pyrrolo[1,2-a]quinoxaline] (PQP) were synthesized. The monomers were electropolymerized via potentiodynamic methods in order to understand the effects of donor units on the electrochemical and optoelectronic properties of the resulting polymers. It was found that polymer films exhibit reversible redox behavior accompanied with a reversible electrochromic behavior ( E p ox = 0.95 V for poly(2,7-di(thiophen-2-yl)-5′H-spiro[Fluorene-9,4’-pyrrolo[1,2-a]quinoxaline]) (PTQT), E p ox = 0.90 V for poly(2,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-5′H-spiro[Fluorene-9,4′-pyrrolo[1,2-a]quinoxaline]) (PEQE) and E p ox = 0.67 V for poly(2,7-bis(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-5′H-spiro[Fluorene-9,4′-pyrrolo[1,2 a]quinoxaline]) (PPQP)). The band gap values (Eg) of the polymers were found to be 2.47, 1.93 and 1.66 eV for PTQT, PEQE and PPQP, respectively. Furthermore, the ion sensitivity of PQP and its polymer PPQP was also investigated by monitoring the change in the fluorescence intensity. Among various common ions, both PQP and PPQP were found to be selective towards Fe2+ ions by quenching the fluorescence efficiency with a Stern–Volmer constant (Ksv) of (5.9 × 103 M−1) and (2.7 × 104 M−1) for monomer and polymer solutions, respectively.
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a new processable electrochromic polymer based on an electron deficient Fluorene Derivative with a high coloration efficiency
2011Co-Authors: Buket Bezgin Carbas, Arif Kivrak, Ahmet M OnalAbstract:Abstract A new fluorenone based soluble polymer, namely poly(2,7-bis-(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-fluoren-9-one) (PPFP), containing propylenedioxythiophene (ProDOT) as a donor and fluorenone (FO) as an acceptor group is highlighted. Electrochemical polymerization of 2,7-bis-(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-fluoren-9-one (PFP) was achieved in dichloromethane/acetonitrile mixture with 0.1 M tetrabutylammonium hexafluorophosphate via potential cycling. The polymer shows an electrochromic behavior, a color change from orange to dark blue during oxidation with a high coloration efficiency (422 cm 2 /C at 684 nm) and orange to yellow during reduction with high optical and electrochemical stability as compared to its close analogues, in addition it is found to be both p and n dopable. Furthermore, this soluble polymer exhibits fluorescent properties (the emission of orange light (578 nm) in THF solution).
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electrochemical polymerization of an electron deficient Fluorene Derivative bearing ethylenedioxythiophene side groups
2010Co-Authors: Buket Bezgin, Ahmet M OnalAbstract:Abstract A new low band gap polyFluorene Derivative, poly(2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one) (PEFE), containing ethylenedioxythiophene as donor and fluorenone (FO) as an acceptor groups was electrochemically synthesized. Electrochemical polymerization of 2,7-bis-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-5-yl)-fluoren-9-one (EFE) was achieved in dichloromethane with 0.1 M tetrabutylammonium-hexafluorophosphate both via and potentiostatic methods. The polymer was characterized by cyclic voltammetry, UV–vis, FT-IR and NMR spectroscopic techniques. Spectroelectrochemical and electrochemical analysis revealed that the polymer film is both p- and n-dopable and can be successfully cycled and switched between its neutral and oxidized/reduced states. Furthermore, PEFE shows electrochromic behavior by a color change from brown to blue with a switching time of 1.65 s during oxidation with a high coloration efficiency (250 cm2/C). Fluorescence studies were also performed.
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electrochemical co polymerization of a novel Fluorene Derivative with 3 4 ethylenedioxythiophene
2009Co-Authors: Buket Bezgin, Aziz Yagan, Ahmet M OnalAbstract:Abstract The co-polymerization of a novel Fluorene Derivative, N-(9H-fluoren-9-ylidene)benzamine (FBA), with 3,4-ethylenedioxythiophene (EDOT) was successfully achieved in acetonitrile via direct anodic oxidation of the monomer mixtures both on platinum and indium-tin oxide working electrodes. The characterization of copolymer films, poly(EDOT-co-FBA), was carried out utilizing electrochemical, spectroelectrochemical, electrochemical impedance (EIS), and FT-IR techniques. It is found that poly(EDOT-co-FBA) films which were synthesized with a feed ratio of FBA/EDOT 5/2 via both potentiodynamically and potentiostatically, had different properties than that of electrochemically prepared poly(3,4-ethylenedioxythiophene) (PEDOT) film. Spectroelectrochemical investigations revealed that copolymer films exhibit relatively lower band gap (1.63 eV) than that of polyFluorenes. Electrochemical impedance spectroscopy (EIS) was also employed to investigate both the resistance and capacitance properties of copolymer coatings.
Mitsunobu Nakamura - One of the best experts on this subject based on the ideXlab platform.
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photoluminescent color tuning in Fluorene Derivative copolymer composite films based on h bonds
2012Co-Authors: Nobuhiro Kawatsuki, Hisako Miki, Mizuho Kondo, Mitsunobu NakamuraAbstract:Reversible addition–fragmentation chain transfer (RAFT) polymerization is used to synthesize diblock and random copolymers of poly[(2-trifluoroethyl methacrylate)-co-(methacrylic acid)]. Copolymer films doped with Fluorene Derivatives comprised of pyridine groups exhibit reversible photoluminescent (PL) color tuning by adjusting the location of Fluorene Derivatives in H-bonds or non-H-bonds environments. The composite films exhibit green and blue photoluminescence with and without effective H-bonding between the pyridine ring in the Fluorene Derivative and the carboxylic acid side group, respectively. At elevated temperatures, the H-bonded structure dissociates and the Fluorene Derivative migrates to the hydrophobic block in the diblock polymer, and they do not form H-bonds upon cooling. However, re-formation of H-bonds also occurs upon cooling random copolymers. Moreover, adjusting the annealing temperature and the solvent annealing reversibly tunes the PL color in the diblock copolymer composite films.
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Photoluminescent Color Tuning in Fluorene Derivative/Copolymer Composite Films Based on H-Bonds
2012Co-Authors: Nobuhiro Kawatsuki, Hisako Miki, Mizuho Kondo, Mitsunobu NakamuraAbstract:Reversible addition–fragmentation chain transfer (RAFT) polymerization is used to synthesize diblock and random copolymers of poly[(2-trifluoroethyl methacrylate)-co-(methacrylic acid)]. Copolymer films doped with Fluorene Derivatives comprised of pyridine groups exhibit reversible photoluminescent (PL) color tuning by adjusting the location of Fluorene Derivatives in H-bonds or non-H-bonds environments. The composite films exhibit green and blue photoluminescence with and without effective H-bonding between the pyridine ring in the Fluorene Derivative and the carboxylic acid side group, respectively. At elevated temperatures, the H-bonded structure dissociates and the Fluorene Derivative migrates to the hydrophobic block in the diblock polymer, and they do not form H-bonds upon cooling. However, re-formation of H-bonds also occurs upon cooling random copolymers. Moreover, adjusting the annealing temperature and the solvent annealing reversibly tunes the PL color in the diblock copolymer composite films
Houjie Liang - One of the best experts on this subject based on the ideXlab platform.
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saturated deep blue emitter based on a spiro benzoanthracene Fluorene linked phenanthrene Derivative for non doped organic light emitting diodes
2014Co-Authors: Houjie Liang, Xinxin Wang, Xingye Zhang, Zhiyang Liu, Xinhua Ouyang, Suidong WangAbstract:A spiro[benzoanthracene–Fluorene] Derivative containing a phenanthrene moiety, 2′,3-di(phenanthren-9-yl)spiro[benzo[de]anthracene-7,9′-Fluorene] (DPSBAF), was prepared by a Suzuki coupling reaction. The photophysical and photochemical properties were investigated systematically. A non-doped organic light-emitting diode using DPSBAF as the emitter achieved a luminance efficiency of 2.18 cd A−1 with Commission Internationale de l'Eclairage 1931 chromaticity coordinates of (0.15, 0.09). The synthesized spiro[benzoanthracene–Fluorene] Derivative with a high thermal stability, a glass transition temperature of 210 °C and a decomposition temperature of 410 °C, shows potential for application in non-doped saturated deep-blue organic light-emitting diodes.
Jose M Garcia - One of the best experts on this subject based on the ideXlab platform.
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solid polymer and metallogel networks based on a Fluorene Derivative as fluorescent and colourimetric chemosensors for hg ii
2014Co-Authors: Jesus L Pablos, Felix C Garcia, Felipe Serna, Saturnino Ibeas, Asuncion Munoz, Jose M GarciaAbstract:Abstract This work describes two sensing systems for the detection and quantification of Hg(II): (a) a highly tractable solid polymer membrane, and (b) a gelling system based on a low molecular weight gelator. The preparation of both sensory systems relies on a polymerisable acrylic monomer derived from a Fluorene core containing a functional hydroxyimino group, which at the same time is an organogelator with Hg(II)-triggered gelating properties in organic solution. The polymerisation of this monomer with commercial comonomers gave a cross-linked membrane or film, which permitted the detection of Hg(II) using UV/Vis and fluorescence techniques due to the colour and fluorescence changes in response to the interaction of the film with Hg(II). At the same time, organic solutions of the monomer – or gelator – gave a gel upon interacting with Hg(II). Engineering of the gel formation conditions permitted the tuning of the visual detection threshold of the concentration of Hg(II), which ranged from 6 × 10−3 to 1 × 10−2 M in our study, while the membrane permitted the detection by UV/Vis and fluorescence spectroscopy of Hg(II) in organic and organic/aqueous media in the millimolar–micromolar range. Furthermore, the colour and fluorescence changes of the two systems were clearly visible, allowing for the naked-eye detection and broad quantification of milli to micromolar concentrations of Hg(II).
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working with water insoluble organic molecules in aqueous media Fluorene Derivative containing polymers as sensory materials for the colorimetric sensing of cyanide in water
2011Co-Authors: Saul Vallejos, Pedro Estevez, Felix C Garcia, Felipe Serna, Jose L De La Pena, Hamid El Kaoutit, Jose M GarciaAbstract:This paper describes a strategy followed to achieve a sensing phenomenon in aqueous media using water-insoluble organic molecules. We have prepared a methacrylamide and a methacrylate with pendant cyanide chemosensors based on a Fluorene-Derivative motif, and we have fabricated highly hydrophilic membranes by means of copolymerising these hydrophobic monomers with others. Therefore, upon absorption of water in the membranes, solvated ions enter the membrane by a simple diffusion mechanism, reaching the hydrophobic chemosensor motifs and giving rise to a macroscopic sensing phenomenon. In this way, we have prepared solid materials (dense membranes or films) capable of selectively detecting cyanide, with an extremely low detection threshold, in aqueous solution by means of colour changes (naked-eye sensing) (13 ppb). Nevertheless, the key point of this research is the description of the possibilities of anchoring organic insoluble molecules (i.e., drugs, fungicides, bactericides, sensing probes, etc.) to solubilise them in water, or to prepare hydrogels, permitting the use of these molecules in aqueous media or in biological media for medical, biological or biochemical purposes.
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putting to work organic sensing molecules in aqueous media Fluorene Derivative containing polymers as sensory materials for the colorimetric sensing of cyanide in water
2010Co-Authors: Saul Vallejos, Pedro Estevez, Felix C Garcia, Felipe Serna, Jose L De La Pena, Jose M GarciaAbstract:This paper describes a strategy followed to achieve a sensing phenomenon in aqueous media using water-insoluble organic molecules. A sensory polymeric material for the colorimetric sensing of cyanide in water has been developed based on the reactivity of this anion with a Fluorene Derivative.