共查询到20条相似文献,搜索用时 31 毫秒
1.
Sugiyasu K Honsho Y Harrison RM Sato A Yasuda T Seki S Takeuchi M 《Journal of the American Chemical Society》2010,132(42):14754-14756
Herein, we report on a self-threading polythiophene whose conjugated molecular wire is sheathed within its own cyclic side chains. The defect-free insulating layer prevents electronic cross-communication between the adjacent polythiophene backbone even in the solid film. Notably, the covalently linked cyclic side chains extend the effective conjugation length of the interior polythiophene backbone, which results in an excellent intrawire hole mobility of 0.9 cm(2) V(-1) s(-1). 相似文献
2.
3.
The electrochromic properties of a polythiophene polyrotaxane film consisting of a polythiophene backbone wrapped by the tetra-cationic cyclophane, cyclobis(paraquat-p-phenylene), were characterized. A naked reference polythiophene film, i.e., polythiophene without tetra-cationic cyclophane, was also characterized. The surface morphology and thickness of the film (L) were observed by atomic force microscopy. The surface of the naked reference polythiophene film has micrometer-scale polythiophene aggregates, which causes the darker color of the film and smaller color contrast in the electrochromic process. The polythiophene polyrotaxane gives a more homogeneous and brighter colored film owing to the suppression of molecular interactions between the polythiophene chains by the tetra-cationic cyclophanes. Potential-step chronoamperometric measurement provided the area density of the oxidizable sites (Γ) and the apparent diffusion coefficient of the charge transport in the film. From linear relationship between L and Γ, the concentrations of the oxidizable sites in the polythiophene polyrotaxane and naked reference polythiophene films were calculated to be 1.3 and 2.4 mmol cm(-3), respectively. Interestingly, the polythiophene polyrotaxane film afforded a significantly larger apparent diffusion coefficient than the naked reference polythiophene film. This result suggests that the rate-determining step of the charge transport is not the electron hopping between the polythiophene chains but the transport of charge-compensating counterions from the solvent into the polythiophene. We believe that the counteranions of the tetra-cationic cyclophane provide a pathway allowing the charge-compensating counteranions to migrate from the solvent to polythiophene. The polythiophene polyrotaxane film showed faster color change than the naked reference polythiophene film in the electrochromic reaction. These results indicate that our polythiophene polyrotaxane is a better electrochromic material than the naked reference polythiophene. 相似文献
4.
报道了3种取代聚噻吩,3-己基聚噻吩(P3HT)、3,4-二戊基聚噻吩(P34PT)、3-辛氧基聚噻吩(P3OOT)的合成方法1、H-NMR测试结果及UV-Vis吸收光谱和荧光光谱分析结果。用密度泛函方法计算了无取代噻吩、3-乙基噻吩、3,4-二乙基噻吩、3-乙氧基噻吩二聚体的电子性能。随聚合度的提高,聚合物能隙变窄。无取代噻吩二聚体的能隙为4.216 eV,重复单元长度为0.392 7 nm;乙基取代噻吩二聚体的能隙为4.733 eV,重复单元长度为0.393 9 nm;乙氧基取代噻吩二聚体的能隙为3.890 eV,重复单元长度为0.390 8 nm;双乙基取代噻吩二聚体的能隙为5.168 eV,重复单元长度为0.392 5 nm。理论变化规律与实验结果基本一致。 相似文献
5.
The electronic properties of three types of conducting polymers: trans-polyacetylene (proto-typical of systems with a degenerate ground state), polythiophene (as an example of compounds with a nondegenerate ground state), and polyemeraldine (which can be doped via protonation) are reviewed. The structural and electronic band structure properties of these systems are studied at various defect concentrations corresponding to undoped, lightly doped, and highly doped polymers. Geometry optimizations of oligomeric equivalents to the undoped and doped polymers are performed using the semi-empirical MNDO and AM1 methods. The electronic band structures are calculated using the VEH method. The interpretation of the optical absorption data is discussed in terms of interband transitions; for doped trans-polyacetylene including soliton defects and for doped polythiophene including bipolaron defects. For highly doped trans-polyacetylene and polythiophene as well as for protonated polyemeraldine, the electronic structure of a polaron lattice conformation is discussed and shown to be in agreement with existing optical and magnetic data on these polymers. 相似文献
6.
Koei Azuma Takahiro Komamura Alvin Chandra Fuminobu Kato Yuta Nabae Teruaki Hayakawa 《Journal of polymer science. Part A, Polymer chemistry》2019,57(10):1105-1112
A new class of periodically nanostructured polythiophene materials with high regularity and numerous morphologies is prepared through the cooperative self‐assembly of polythiophene derivatives with a templating block copolymer (BCP) and poly(1,4‐isoprene)‐block‐poly(methacrylic acid) (PMA). The selection of the hydrophilic and aprotic triethylene glycol (TEG) group as side chains on polythiophene and the use of hydrophilic and protic PMA are crucial to producing well‐ordered nanostructures in polythiophene films, as it enables selective coassembly within the hydrophilic domain through hydrogen bonding. The composite films are shown to have formed hexagonally packed cylinders with 28 nm periodicities based on small‐angle X‐ray scattering and transmission electron microscopy. The formation of hydrogen bonding is revealed by a shift in the carbonyl peak of PMA in the Fourier transform infrared spectra of the composite film relative to the neat film. This suggests that the TEG‐functionalized polythiophene selectively incorporates into PMA. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1105–1112 相似文献
7.
本文用LCAO-CO/EHMO方法对噻吩高聚物的类苯结构(Ⅰ)、类等键长结构(Ⅱ)以及类酸结构(Ⅲ)的电子能带、态密度及电荷分布进行了计算。通过对计算结果的分析, 探讨了噻吩高聚物导电机理的有关问题。 相似文献
8.
Shun‐ichi Tamaru Miyabi Honzaki Kinosuke Kamogawa Kaori Hori Miki Kubo Naofumi Kuroda Seiji Shinkai 《化学:亚洲杂志》2019,14(12):2102-2107
The semi‐artificial branched‐polysaccharides, amylose‐grafted curdlans, were synthesized utilizing an enzymatic polymerization. Both a curdlan main chain and amylose side chains on the polysaccharides maintain the original helical structure as well as the molecular binding ability. Thanks to the difference in their molecular recognition properties between β‐1,3‐glucan chain and α‐1,4‐glucan chain, the amylose‐grafted curdlans can provide two different orthogonal binding sites within one polymeric system. When a water‐soluble polythiophene was mixed with the amylose‐grafted curdlan, the polythiophene was twisted in two different modes and therein, fluorescence energy of the polythiophene wrapped by the amylose side chains was successfully transferred to the polythiophene wrapped by the curdlan main chain. We thus concluded that in the dendritic superstructure of this polysaccharide, a self‐organized “Janus‐type FRET system” was successfully constructed. 相似文献
9.
van Beek R Zoombelt AP Jenneskens LW van Walree CA de Mello Donegá C Veldman D Janssen RA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(31):8075-8083
The properties of a mixed CdTe quantum dot/tetrahydro-4H-thiopyran-4-ylidene-functionalized polythiophene system are reported. This system was prepared by exposing trioctylphosphine (TOP)-capped CdTe quantum dots to the polythiophene in solution. Strong fluorescence emission quenching and shortening of the fluorescence emission lifetimes of both the polythiophene and the quantum dots occur when they are mixed, indicating the occurrence of photoinduced charge separation. Photoinduced absorption spectroscopy reveals a considerable decrease in the population of the polythiophene triplet excited state in the mixed system. These results demonstrate that between the quantum dots and the polythiophene there is both physical and electronic contact, which is mediated by the tetrahydro-4H-thiopyran-4-ylidene side chains. 相似文献
10.
本文运用STM及SEM确定处理固相离子传导的基体形状为球形; 用改进的GITT方法(间隙库仑滴定法)计算了离子的扩散系数, 在10^-^1^0~10^-^1^2cm^2.s^-^1量级; 运用XPS方法证明了界面的部分电荷转移。建立了阴离子(ClO~4^-)在导电聚合物(聚噻吩)中的电化学嵌入反应的动力学表达式。将上述模型应用于ClO~4^-在聚噻吩(PT)中的嵌入反应。所得结果表明, 在脱嵌态聚噻吩的交换电流很小, 与它的半导体性质一致。同时, α+β<1, 再次证明了界面的部分电荷转移。 相似文献
11.
Soumitra Satapathi Fadong Yan Robinson Anandakathir Ke Yang Lian Li Ravi Mosurkal 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1180-1183
Photovoltaic performance of dye sensitized solar cells fabricated with a commercially available thiophene based copolymer was investigated. Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(bithiophene)], a highly soluble polythiophene, was used as a sensitizer. An open-circuit voltage of 0.64 V and a short-circuit current density of 0.36 mA/cm2 were measured. The incident photon to current conversion efficiency for the polymer was measured. Fluorescence from the other polythiophene, poly(3,3′-didodecyl quarter thiophene) was found to be quenched when blended with phenyl C61 butyric acid methyl ester (PCBM) (1:1 wt ratio), indicating the charge transfer from the conjugated polymer to PCBM. 相似文献
12.
In this study, we demonstrate a novel method for fabricating polythiophene patterns, i.e., cylindrical holes and cylinders, through blending of a thermally curable polythiophene carrying with tertiary ester groups (PT-tert-ESTER) and poly(methyl methacrylate) (PMMA), followed by thermal conversion of the PT-tert-ESTER to an insoluble polythiophene via low-temperature cleavage of the tertiary ester groups and removal of the PMMA component via ultraviolet degradation. We show that the surface polarity of substrates, the mass ratio of PT-tert-ESTER to PMMA in the blend solutions as well as the concentration of the blend solutions strongly influence the formation of the polythiophene patterns. Cylindrical holes are more readily formed on less polar substrates when a PT-tert-ESTER dominated blend solution is used, while cylinders are more readily formed on more polar substrates when a PMMA dominated blend solution is used. Moreover, the diameters of both the cylindrical holes and the cylinders decrease as the PT-tert-ESTER concentration is increased in the respective ranges of the PT-tert-ESTER/PMMA ratios where the patterns are formed. Grazing incident X-ray diffraction data have indicated that the patterning of the PT-tert-ESTER component in the blend films improves the crystallinity of PT-tert-ESTER as well as the molecular packing of the insoluble polythiophene in the resultant patterned polythiophene films. 相似文献
13.
《Electrochemistry communications》2003,5(8):625-631
Composite using polythiophene as the conducting polymer and different silica sol–gel as the host matrix were prepared by the template method. The electrochemical performance of the composites has been confirmed using cyclic voltammetry and was compared with the results obtained on polythiophene films synthetised under the same condition directly on ITO substrates. UV–Vis–NIR spectroscopy, scanning electron and atomic force microscopic measurements were done on all the different composites. 相似文献
14.
A series of polythiophene derivatives with substantially higher azobenzene contents in the side chains were prepared via copolymerization of 3‐hexylthiophene with four different types of 4‐((4‐(phenyl)azo)phenoxy)alkyl‐3‐thienylacetate. The alkyl spacers with different lengths, i.e. butyl, hexyl, octyl and undecyl groups were used between the azobenzene group and the thiophene ring. The compositions, structures and thermal properties of these polythiophene derivatives were characterized. The structural dependence of photoluminescent emission, photochromic behavior of these copolymers were systematically studied and compared with poly(3‐hexylthiophene). The results show that the azobenzene substitution renders the polythiophene some interesting optical properties that can be modulated by UV light irradiation. In the azobenzene modified polythiophene, the intensity of photoluminescent emission associated with the conjugated polythiophene main chain was found to decrease significantly upon UV irradiation. The finding suggests that the photo‐induced trans‐cis isomerization of the azobenzene pendant groups has a significant effect on photoluminescent emission, particularly when short spacers are used between azobenzene groups and the main chain. However, the effect becomes less prominent when longer spacers are used between the azobenzene group and the main chain. Furthermore, UV irradiation of the copolymers also resulted in an increase in intensity and broadening of bandwidth for the absorption peak associated with the polythiophene backbones. Again the magnitude of intensity changes upon UV irradiation were found to be dependent on the spacer length between the azobenzene group and polythiophene main chain. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
15.
An in situ hybrid complex of Curdlan with water-soluble polythiophene functioned as a highly sensitive and selective saccharide chemosensor in aqueous media, enabling us to discriminate tetrasaccharide acarbose at 1 μM from 24 mono-, di-, tri-, tetra-, and pentasaccharides. 相似文献
16.
17.
Ruting Yang Shaoqing Wang Kaikai Zhao Yuguang Li Chenjun Li Yiben Xia Yinfeng Liu 《Polymer Science Series B》2017,59(1):16-27
Precipitation method of oxidation polymerization for preparing polythiophene was carried out as well as dispersion and emulsion methods in aqueous medium by using (NH4)2S2O8 and CuCl2 as the oxidant and catalyst, respectively. In precipitation method, ethanol was served as an auxiliary solvent to water. The effective conjugated length (ECL) of the obtained polythiophene was demonstrated to be evaluated by the UV absorption spectrum. The ECL of the polythiophene gradually increases with the rise of the content of ethanol in the mixed solvent in precipitation polymerization, and it was higher comparing to the ECL of the product prepared by aqueous dispersion or emulsion method. An electron transition mechanism of the oxidation polymerization of thiophene was suggested. 相似文献
18.
Sihui Deng Changshuai Dong Prof. Jian Liu Dr. Bin Meng Prof. Junli Hu Yang Min Prof. Hongkun Tian Prof. Jun Liu Prof. Lixiang Wang 《Angewandte Chemie (International ed. in English)》2023,62(18):e202216049
Typical n-type conjugated polymers are based on fused-ring electron-accepting building blocks. Herein, we report a non-fused-ring strategy to design n-type conjugated polymers, i.e. introducing electron-withdrawing imide or cyano groups to each thiophene unit of a non-fused-ring polythiophene backbone. The resulting polymer, n-PT1 , shows low LUMO/HOMO energy levels of −3.91 eV/−6.22 eV, high electron mobility of 0.39 cm2 V−1 s−1 and high crystallinity in thin film. After n-doping, n-PT1 exhibits excellent thermoelectric performance with an electrical conductivity of 61.2 S cm−1 and a power factor (PF) of 141.7 μW m−1 K−2. This PF is the highest value reported so far for n-type conjugated polymers and this is the first time for polythiophene derivatives to be used in n-type organic thermoelectrics. The excellent thermoelectric performance of n-PT1 is due to its superior tolerance to doping. This work indicates that polythiophene derivatives without fused rings are low-cost and high-performance n-type conjugated polymers. 相似文献
19.
N. Maximilian Bojanowski Christian Huck Lisa Veith Karl-Philipp Strunk Rainer Buerle Christian Melzer Jan Freudenberg Irene Wacker Rasmus R. Schrder Petra Tegeder Uwe H. F. Bunz 《Chemical science》2022,13(26):7880
We report the electron-beam induced crosslinking of cinnamate-substituted polythiophene proceeding via excited state [2+2]-cycloaddition. Network formation in thin films is evidenced by infrared spectroscopy and film retention experiments. For the polymer studied herin, the electron-stimulated process appears to be superior to photo (UV)-induced crosslinking as it leads to less degradation. Electron beam lithography (EBL) patterns cinnamate-substituted polythiophene thin films on the nanoscale with a resolution of around 100 nm. As a proof of concept, we fabricated nanoscale organic transistors using doped and cross-linked P3ZT as contact fingers in thin film transistors.Electron beam lithography patterns selectively cinnamate-substituted polythiophene thin films via [2+2]-cycloaddition. A nanoscale organic field effect transistor is constructed using cross-linked and doped polythiophene as electrodes. 相似文献
20.
Jie Shen Kousuke Tsuchiya Kenji Ogino 《Journal of polymer science. Part A, Polymer chemistry》2008,46(3):1003-1013
In this study, macroinitiators with different content of atom‐transfer radical polymerization (ATRP) functional group on polythiophene backbone were first prepared by the copolymerization of 3‐[1‐ethyl‐2‐(2‐bromopropionate)]thiophene and 3‐hexylthiophene with various feed ratio. Then poly [3‐hexyl‐2,5‐thienylene‐co‐3‐[1‐ ethyl‐2‐(2‐[poly(styrene)]propionate)]‐2,5‐thienylene] (PTTBr‐PS) with different graft density were obtained by ATRP of styrene from these macroinitiators in anisole. The degree of polymerization of PS sidearm (DPPS) was controlled by polymerization time. The structures of obtained graft copolymers were characterized by gel permeation chromatography (GPC), nuclear magnetic resonance (1H NMR) and differential scanning calorimetry (DSC). Introduction of the PS sidearms onto the backbone of polythiophene was an attempt to trap the polythiophene backbone in a “solution‐like” conformation, thus inhibit the packing of polythiophene backbone and result in the improvement of fluorescent property in solid state. This was verified by the UV–vis and fluorescence analyses. Besides, it was also found that the optical property of PTTBr‐PS graft copolymer was dominated by its graft density and independent on the degree of polymerization of its PS sidearm. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1003–1013, 2008 相似文献