196207-58-6Relevant articles and documents
Synthesis and light-emitting properties of new polyfluorene copolymers containing 2,3-diphenylfumaronitrile
Mi, Dongbo,Kim, Hee Un,Lee, Seon Young,Lee, Jonghee,Hong, Sung-Chul,Pyo, Sungmoon,Hwang, Do-Hoon
, p. 64 - 73 (2010)
A series of polyfluorene copolymers composed of 9,9-dioctylfluorene (DOF) and 2,3-diphenylfumaronitrile (DPFN), poly(DOF-co-DPFN)s, have been synthesized through a palladium (0)-catalyzed Suzuki coupling reaction, and their light-emitting properties have
Effect of Arylmethylene Substitutions on Molecular Structure, Optoelectronic Properties and Photovoltaic Performance of Dithienocyclopentafluorene-Based Small-Molecule Acceptors
Tang, Xuejiao,Liao, Haitao,Zheng, Tao,Yin, Pan,Cao, Jing,Zeng, Xiaoying,Weng, Chao,Shen, Ping
, p. 14508 - 14519 (2021)
Two dithienocyclopentafluorene-based small-molecule acceptors (SMAs) were developed that feature methylene-functionalized conjugated side chains, to study the effect of arylmethylene substitution and its number on structure, optoelectronic properties and device performance. Results showed that two SMAs have better absorption properties and planarity, lower bandgaps and higher LUMOs compared with the control SMA without conjugated side chains. The synthesized SMAs were tested in polymer solar cells for examples of their applicability. This work argues that the introduction of methylene-functionalized conjugated side chains has great potential in tuning molecular structure, optoelectronic properties, device physics and photovoltaic performance of SMAs.
Tunable Control of the Hydrophilicity and Wettability of Conjugated Polymers by a Postpolymerization Modification Approach
Cong, Shengyu,Creamer, Adam,Fei, Zhuping,Hillman, Sam A. J.,Rapley, Charlotte,Nelson, Jenny,Heeney, Martin
, (2020)
A facile method to prepare hydrophilic polymers by a postpolymerization nucleophillic aromatic substitution reaction of fluoride on an emissive conjugated polymer (CP) backbone is reported. Quantitative functionalization by a series of monofunctionalized ethylene glycol oligomers, from dimer to hexamer, as well as with high molecular weight polyethylene glycol is demonstrated. The length of the ethylene glycol sidechains is shown to have a direct impact on the surface wettability of the polymer, as well as its solubility in polar solvents. However, the energetics and band gap of the CPs remain essentially constant. This method therefore allows an easy way to modulate the wettability and solubility of CP materials for a diverse series of applications.
Thieno[3,2-b]thiophene-based conjugated polyfluorene copolymer for efficient polymer solar cell
Kim, Joo Yeon,Kim, Hye-Min,Lee, Ja-Eun,Kim, Tae-Dong,Baek, Nam Seob
, p. 6331 - 6336 (2014)
We have synthesized and characterized a polyfluorene derivative composed of octyl-substituted thieno[3,2,-b]thiophene and 2,1,3-benzothiadiazole as an acceptor unit. The best power conversion efficiencies of the polymer were showed with 1.63% and 2.31% by using PCBM and PC71BM, respectively. Copyright
4-hexylbithieno[3,2-b:2′3′-e]pyridine: An efficient electron-accepting unit in fluorene and indenofluorene copolymers for light-emitting devices
Sonar, Prashant,Zhang, Jingying,Grimsdale, Andrew C.,Müllen, Klaus,Surin, Mathieu,Lazzaroni, Roberto,Leclère, Philippe,Tierney, Steve,Heeney, Martin,McCulloch, Iain
, p. 709 - 715 (2004)
4-Hexylbithienopyridine has been prepared as a novel electron-accepting monomer for conjugated polymers. To test its electronic properties, alternating copolymers with fluorene and indenofluorene polymers have been prepared. The copolymers displayed reduction potentials about 0.5 V lower than for the corresponding fluorene and indenofluorene homopolymers, indicating much improved electron-accepting properties. Analysis of the microscopic morphology of thin films of the copolymers by AFM shows that they lack the extensive supramolecular order seen with the homopolymers, which is attributed to the bithienopyridine units disrupting the π-stacking. LEDs using these polymers as the emitting layer produce blue-green emission with low turn-on voltages with aluminum electrodes confirming their improved electron affinity. The indenofluorene copolymer displayed an irreversible red shift in emission at high voltages, which is attributed to oxidation of the indenofluorene units. This red shift occurred at higher potentials than for indenofluorene homopolymers in LEDs, suggesting that the heterocyclic moieties offer some protection against electrically promoted oxidation.
Diastereoselective Radical Oxidative C-H Aminations toward Chiral Atropoisomeric (P, N) Ligand Precursors
Ma, Yan-Na,Cheng, Ming-Xing,Yang, Shang-Dong
, p. 600 - 603 (2017)
A new class of chiral atropoisomeric (P, N) ligand precursors has been obtained with excellent diastereoselectivities and high yields through diastereoselective metal-free intramolecular radical oxidative C-H amination with chiral phosphamide as the auxil
Effective structural modifications enabled by end-capped effects based on fluorene-core donor, with high open-circuit voltage in organic photovoltaic devices
Hu, Chunxiao,Li, Yanqin,Xie, Bao,Yin, Lunxiang
, (2020)
End-capped effects are important in modifying the structures of donor materials, with the purpose of regulating material properties and achieving high open-circuit voltage (VOC). A series of acceptor-π-donor-π-acceptor (A-π-D-π-A) type small-molecule donor (SMD) materials for bulk-heterojunction (BHJ) organic solar cells with PC71BM as electron acceptor have been designed and synthesized. Three novel small molecules are denoted as flu(3TRD)2, flu(3TCN)2 and flu(3TIN)2, with dioctyl-substituted fluorene as core, 3,3″-dioctyl-2,2':5′,2″-terthiophene as π-bridge, terminated by rhodanine, malononitrile and 1,3-indanedione, respectively. Improvements of photovoltaic performance have been successfully realized via tuning terminal electron-withdrawing units. The power conversion efficiency (PCE) of the devices as-cast prepared from flu(3TRD)2, flu(3TCN)2 and flu(3TIN)2 increases in turn, which is ascribed to incremental optical absorption thereby promoting short-circuit current density (JSC). Particularly, flu(3TCN)2 shows deeper LUMO and HOMO energy levels than flu(3TRD)2 and flu(3TIN)2 due to the strong electron-withdrawing character of malononitrile. As expected, the device as-cast based on flu(3TCN)2 exhibits a reasonable high VOC of 1.07 V. In addition, a satisfactory PCE of 7.06percent has been obtained for flu(3TCN)2 based device with dichloromethane vapor treatment.
Facile photopatterning of polyfluorene for patterned neuronal networks
Baek, Nam Seob,Kim, Yong Hee,Han, Young Hwan,Lee, Bong Joon,Kim, Tae-Dong,Kim, Sin-Tae,Choi, Young-Seok,Kim, Gook Hwa,Chung, Myung-Ae,Jung, Sang-Don
, p. 10025 - 10031 (2011)
In this paper, we demonstrated a facile photopatterning method that uses photocrosslinkable polyfluorene to fabricate micro-sized photopatterns on transparent indium tin oxide substrate for neuronal patterning. The modified poly(ethyleneimine) (m-PEI) with trimethoxysilane moiety was chemically attached to the hydroxyl group-terminated ITO surface and then the photopatternable polyfluorene derivative was spin coated as a cell-repellent layer onto the m-PEI-coated surface. The well-defined micropatterns were easily created over an entire surface by photocrosslinking of bromoalkyl-substituted polyfluorene (Br-PF) via the radical coupling reaction of a C-Br bond under UV irradiation without an initiator. UV-Vis absorbance, photoluminescence, ATR-FTIR and X-ray photoelectron spectroscopy were used to confirm the photocrosslinking process and the surface composition before and after the photocrosslinking of polyfluorene. The pairing of adhesive m-PEI and repulsive Br-PF effectively guided the neurite outgrowth and controlled neurite extension from individual neurons to the pre-patterned direction with excellent pattern fidelity. Guided neuronal cells were maintained for at least 25 days in vitro without any detachment of neuronal cells during cell culture. A photopatternable polyfluorene derivative in combination with cell-adhesive m-PEI is proved to be an effective way to modify the electrode surface to achieve single cell level neuronal networks.
Novel fluorene/trifluoromethylphenylene copolymers: Synthesis, spectra stability and electroluminescence
Zhang, Ting,Deng, Lijun,Wang, Renjie,Zhou, Wei,Li, Jiuyan
, p. 380 - 385 (2012)
A group of novel fluorene-based copolymers were synthesized and characterized. The trifluoromethylphenylene unit was introduced into the copolymer backbone and its content ratio was varied from 10 mol% to 50 mol%. The electronic bandgap of the copolymer increases regularly with increasing trifluoromethylphenylene ratio. In contrast to pure polyfluorene, the deep-blue fluorescence of these copolymers is quite stable and not contaminated by the well-known green emission associated with fluorenone defects. The copolymers were used as an emitting layer to fabricate organic light-emitting diodes with a pure blue electroluminescence with a CIE coordinate y ≤ 0.10 obtained for most copolymers. Whilst the presence of the trifluoromethylphenylene units in the copolymers seemed unfavorable for charge injection and device current, improved spectral purity and stability in both the photoluminescence and electroluminescence were noted and ascribed to the electron-withdrawing nature of the trifluoromethylphenylene units and the enhanced anti-autoxidation ability of the fluorene rings in these copolymers.
Synthesis and luminescent properties of fluorene copolymers bearing DCM pendants
Cheon, Cheol Hong,Joo, Sung-Hoon,Kim, Kyungkon,Jin, Jung-Il,Shin, Hee-Won,Kim, Yong-Rok
, p. 6336 - 6345 (2005)
A series of copolymers, poly[(9,9-dioctylfluorene-2,7-diyl) -co-(4-dicyanomethylene-2-methyl-6-[4-(diphenylamino)styryl]-4H-pyran-4′, 4″-diyl], were synthesized by polymerizing 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-dioctylfluorene with mixtures of 2,7-dibromo-9,9-dioctylfluorene and 4-dicyanomethylene-2-methyl-6-[bis(4′-bromophenyl)amino]styryl]-4H-pyran (a DCM derivative) by the palladium-catalyzed Suzuki coupling reaction. The copolymers were characterized by molecular weight determination, elemental analysis, 1H NMR, FT-IR spectroscopy, DSC, TGA, UV-vis spectroscopy, and photoluminescence (PL) and electroluminescence (EL) spectroscopy. The copolymers showed two absorption peaks at 380 and 485 nm, and the long-wavelength absorption increased with increasing the fraction of the DCM comonomer. The PL spectra of copolymers in chloroform solution displayed emission from both the main chain (420 nm) and DCM units (620 nm). In the solid state, however, PL spectra of copolymers showed only the long wavelength red emission at 620 nm with no trace of emission from the main chain, which implies a facile exciton migration or energy transfer to the lower energy sites from the fluorene part to the DCM part. This results in emission of only the red light originating from the latter segments. A study on time-resolved PL rise and decay of the polymers clearly supports the energy transfer mechanism. Light-emitting diode (LED) devices were fabricated to have the configuration of ITO (indiumtin oxide)/PEDOT/polymer/Li:Al alloy. EL spectra of the devices showed only red emissions as observed in the PL spectra of the polymers' thin films. EL efficiency decreased with increasing DCM contents. When a tris(8-hydroxyquinolinato)aluminum (Alq3) layer was inserted between the emitting polymer layer and the cathode to make the ITO/PEDOT/polymer/Alq3/Li:Al alloy configuration, the device efficiencies became much higher (～10-2%) than those (5 × 10-5-5 × 10-3%) of single-layer devices.
Substituent effects on fluorene-based linear supramolecular polymerizsation
Zhang, Guang-Wei,Luo, Meng-Cheng,Lei, Jia-Qi,Zhong, Tao-Tao,Wei, Ying,Xie, Ling-Hai,Huang, Wei
, p. 391 - 401 (2019)
Two supramolecular systems were constructed based on fluorene-based π-conjugated monomers with or without spiro structures, respectively, and their self-assemble behaviour and optical properties were investigated. Concentration-dependent 1H NMR
MATERIALS FOR ORGANIC ELECTROLUMINESCENT DEVICES
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Paragraph 0153; 0154; 0157; 0158, (2021/11/26)
The present invention relates to compounds of the formulae (1) to (4), which are suitable for use in electronic devices, in particular organic electroluminescent devices, to intermediate compounds for the compounds or formulae (1) to (4) and to electronic devices, which comprise the compounds of formulae (1) to (4).
1,2,3-Triazolyl functionalized thiophene, carbazole and fluorene based A-: Alt -B type π-conjugated copolymers for the sensitive and selective detection of aqueous and vapor phase nitroaromatics (NACs)
Giri, Dipanjan,Patra, Sanjib K.
supporting information, p. 14469 - 14480 (2020/11/09)
A series of highly emissive π-conjugated A-alt-B type copolymers (P1-P3) appended with a 1,2,3-triazole moiety was synthesized via Suzuki polymerization. The well-defined and soluble π-conjugated copolymers were characterized via multinuclear NMR spectroscopy and tetradetector GPC studies, showing a molecular weight (Mn) in the range of 16.4-20.1 kDa with a polydispersity index in the range of 1.25-1.42. The synthesized emissive π-conjugated polymer probes were explored as fluorescent chemosensors for nitroaromatic compounds (NACs) in solution, vapor and contact mode. Detailed photophysical and sensing studies were performed to understand the polymer-NAC interaction, inducing the selective fluorescence quenching of the π-conjugated polymer probes through the photoinduced electron transfer (PET) mechanism. All the polymeric probes (P1-P3) were highly reversible in nature with NACs, and thus could be reused multiple times. The limit of detection of the probes towards nitroaromatics was found to be in the range of 120-200 ppb with a high association constant in the order of 104 M-1. Furthermore, test paper kits were also fabricated, which allowed the trace detection of picric acid by the naked eye, making it a practical means for the quick, easy and inexpensive on-site detection of NAC-based explosives.
