121 research outputs found
Interfacial Doping of Organic Semiconductors Accessibled by Anionic p-Dopant CN6-CP•–K+
T. Beryozkina gratefully acknowledges financial support by the Russian Foundation for Basic Research (Рroject № 18-03-00715)
Dithienosilole-based all-conjugated block copolymers synthesized by a combination of quasiliving Kumada and Negishi catalyst-transfer polycondensations
Herein, we present a quasi-living Negishi-type catalyst-transfer polycondensation of a zinc–organic DTSbased monomer which provides an access to narrowly distributed poly(4,4-bis(2-ethylhexyl)dithieno[3,2-b:20,30-d]silole (PDTS) with controlled molecular weight. The synthesis of well-defined all-conjugated diblock copolymers containing a PDTS block was accomplished by a combination of Kumada and Negishi catalyst-transfer polycondensations (KCTP and NCTP, respectively). Particularly, it was shown that living P3HT chains obtained by KCTP of magnesium–organic thiophene-based monomer efficiently initiate NCTP of zinc–organic DTS-based monomer. The purity of the DTS-based monomer was found to be a crucial factor for achieving a clean chain-growth polymerization process. A combination of physico-chemical methods was used to prove the success of the block copolymerization
Remarkable Mechanochromism in Blends of a π-Conjugated Polymer P3TEOT: The Role of Conformational Transitions and Aggregation
A novel mechanism for well-pronounced mechanochromism in blends of a π-conjugated polymer based on reversible conformational transitions of a chromophore rather than caused by its aggregation state, is exemplified. Particularly, a strong stretching-induced bathochromic shift of the light absorption, or hypsochromic shift of the emission, is found in blends of the water-soluble poly(3-tri(ethylene glycol)) (P3TEOT) embedded into the matrix of thermoplastic polyvinyl alcohol. This counterintuitive phenomenon is explained in terms of the concentration dependency of the P3TEOT's aggregation state, which in turn results in different molecular conformations and optical properties. A molecular flexibility, provided by low glass transition temperature of P3TEOT, and the fact that P3TEOT adopts an intermediate, moderately planar conformation in the solid state, are responsible for the unusual complex mechanochromic behavior. © 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimRussian Foundation for Basic Research, RFBR: 18-03-00715Volkswagen FoundationDeutsche Forschungsgemeinschaft, DFG: KI-1094/9-1J.Z. and M.S. contributed equally to the work. The authors gratefully acknowledge support from the Deutsche Forschungsgemeinschaft (DFG) (Grant KI-1094/9-1) and cfaed (ExInI). T.B. gratefully acknowledges financial support by the Russian Foundation for Basic Research (Project 18-03-00715). This project is financially supported by the Volkswagen Foundation through a Freigeist Fellowship to T.A.F.K. The authors acknowledge the Deutsche Forschungsgemeinschaft (DFG) within the Cluster of Excellence ?Center for Advancing Electronics Dresden? (cfaed) for financial support
Solution-Processable Hole-Transporting Polymers: Synthesis, Doping Study and Crosslinking Induced by UV-Irradiation or Huisgen-Click Cycloaddition
A pair of hole-conducting polymers comprising 3,6-linked carbazole and meta-linked anisole derivatives having solubilizing moieties to enable their solution processability, and complementarily reactive side-groups (azide and alkyne) for cross-linking, are synthesized and characterized. The polymers can be cross-linked either by thermal annealing at relatively low temperatures in the 85–110 °C range, or by UV irradiation. A general applicability of the latter for a photolithographic patterning of the hole conducting polymer is proven. The polymers have an ionization potential (IP) of 5.8 eV, close to the IP of a small molecule hole-conductor tris(4-carbazoyl-9-ylphenyl)amine (TCTA). In combination with a strong dopant hexacyano-trimethylene-cyclopropane (CN6CP), but not with commercial 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), the polymers can be efficiently p-doped to increase their conductivity by 5–6 orders of magnitude, as measured in devices with a lateral setup. Taken together, these characteristics suggest that the synthesized polymers are promising candidates for their use in solution-processable organic light-emitting diodes as hole-injection layer and hole-transporting layer materials, which will be verified in the upcoming work. © 2022 The Authors. Advanced Materials Interfaces published by Wiley-VCH GmbH.Technische Universität Dresden, TUD; China Scholarship Council, CSC: 201707040070; European Social Fund, ESF: 100382146; Russian Science Foundation, RSF: 18-13-00161 prolongationE.C.-C. thanks financial support provided by the State budget approved by the delegates of the Saxon State Parliament and by the European Social Fund (ESF) within the project “ReLearning” (SAB appl. No. 100382146) and the “Center for Advancing Electronics Dresden” (CfAED) at the Technische Universität Dresden. T.B. is thankful to Russian Science Foundation (Grant # 18-13-00161 prolongation). K.Z. is grateful to China Scholarship Council (CSC, No. 201707040070) for the financial support. Open access funding enabled and organized by Projekt DEAL.E.C.-C. thanks financial support provided by the State budget approved by the delegates of the Saxon State Parliament and by the European Social Fund (ESF) within the project “ReLearning” (SAB appl. No. 100382146) and the “Center for Advancing Electronics Dresden” (CfAED) at the Technische Universität Dresden. T.B. is thankful to Russian Science Foundation (Grant # 18-13-00161 prolongation). K.Z. is grateful to China Scholarship Council (CSC, No. 201707040070) for the financial support
Cellulose nanofiber backboned Prussian blue nanoparticles as powerful adsorbents for the selective elimination of radioactive cesium
On 11 March 2011, the day of the unforgettable disaster of the 9 magnitude Tohoku earthquake and quickly followed by the devastating Tsunami, a damageable amount of radionuclides had dispersed from the Fukushima Daiichi’s damaged nuclear reactors. Decontamination of the dispersed radionuclides from seawater and soil, due to the huge amounts of coexisting ions with competitive functionalities, has been the topmost difficulty. Ferric hexacyanoferrate, also known as Prussian blue (PB), has been the most powerful material for selectively trapping the radioactive cesium ions; its high tendency to form stable colloids in water, however, has made PB to be impossible for the open-field radioactive cesium decontamination applications. A nano/nano combinatorial approach, as is described in this study, has provided an ultimate solution to this intrinsic colloid formation difficulty of PB. Cellulose nanofibers (CNF) were used to immobilize PB via the creation of CNF-backboned PB. The CNF-backboned PB (CNF/PB) was found to be highly tolerant to water and moreover, it gave a 139 mg/g capability and a million (106) order of magnitude distribution coefficient (Kd) for absorbing of the radioactive cesium ion. Field studies on soil and seawater decontaminations in Fukushima gave satisfactory results, demonstrating high capabilities of CNF/PB for practical applications.National Science Foundation (U.S.) (DMR-1507806
Chain-growth suzuki polymerization of n-type fluorene copolymers
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Designing thiophene-based azomethine oligomers with tailored properties: Self-assembly and charge carrier mobility
Ring walking versus trapping of nickel(0) during kumada catalyst transfer polycondensation using externally initiated electron-accepting thiophene-benzothiadiazole-thiophene precursors
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92279.pdf (publisher's version ) (Open Access)9 p
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