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1.
Poly(3,4‐ethylenedioxythiophene), poly(N‐methylpyrrole), and three‐layered systems made of alternated layers of such two conducting polymers have been prepared by agitating the generation solution through a magnetic bar at a stirring speed of 400 rpm. The influence of these controlled dynamic conditions on both the electrochemical behavior and the superficial morphology has been examined. Results indicate that the increase in transport rate of reactants slightly favors the generation of more polymer weight at equal charge consumed. Consequently, the thickness of the materials prepared under stirring increases considerably with respect to those obtained from quiescent solutions, systems prepared using short (100 s) and large (300 s) polymerization times changing from nanometric to submicrometric and from submicrometric to micrometric length‐scales, respectively. Moreover, the porosity of PNMPy and PEDOT films also increases upon agitation. Thus, quiescent solutions produce compact and cavernous morphologies, respectively, for these materials, whereas the PNMPy and PEDOT obtained from agitated solutions are globular and spongy, respectively. Finally, the electroactivity, electrochemical stability, and electrical conductivity of the materials obtained from stirred solutions have been found to be significantly higher than those of the polymers prepared using quiescent solutions. POLYM. ENG. SCI., 54:2121–2131, 2014. © 2013 Society of Plastics Engineers  相似文献   

2.
Low-cost, flexible and thin display technology is becoming an interesting field of research as it can accompany the wide range of sensors being developed. Here, the synthesis of poly(dimethylpropylene-dioxythiophene) (PProDOT-Me2) by combining vapor phase polymerization and screen printing is presented. A multilayer architecture using poly(3,4-ethylenedioxythiophene) (PEDOT) and PProDOT-Me2 to allow for electrochromic switching of PProDOT-Me2, thereby eliminating the need for a supporting transparent conductive (metal oxide) layer is introduced. Furthermore, the technology is adapted to a blended architecture, which removes the additional processing steps and results in improved color contrast (∆E* > 25). This blend architecture is extended to other conductive polymers, such as PEDOT and polypyrrole (PPy), to highlight the ability of the technique to adjust the color of all-printed electrochromic displays. As a result, a green color is obtained when combining the blue and yellow states of PEDOT and PPy, respectively. This technology has the potential to pave the way for all-printed multicolored electrochromic displays for further utilization in printed electronic systems in various Internet of Things applications.  相似文献   

3.
Multilayered films made with at least two different electroactive polymers, in which the least conducting one acts as a dielectric and separates the layers made with the other, behave as efficient electrodes for electrochemical supercapacitors. In this work, we present a simple strategy to develop improved multilayered electrodes with structured interfaces by enhancing the porosity of the dielectric. This has been achieved by growing sodium chloride crystals onto a conducting polymer layer and, after generation of all required layers using the layer‐by‐layer electrodeposition technique, salt crystals have been eliminated by water etching. Results from morphological and topographical studies on single‐layered poly(3,4‐ethylenedioxythiophene) (PEDOT), poly(N‐methylpyrrole) (PNMPy), and poly(3,4‐ethylenedioxythiophene‐coN‐methylpyrrole) (COP), as well as electrochemical investigations on bi‐layered films with enhanced porosity at the interface between the two layers, have been used to design new four‐layered electrodes. These consist in two layers of PEDOT separated by two layers of nanosegregated COP with a porous interface in the middle. Although the properties of the new four‐layered electrodes improve due to the porous interface, the highest specific capacitance corresponds to the two‐layered electrode in which two PEDOT layers are separated by an ultra‐porous interface. POLYM. ENG. SCI., 59:1624–1635 2019. © 2019 Society of Plastics Engineers  相似文献   

4.
Conducting polymers of alkylanilines, pyrrole, and their conducting composites were synthesized by oxidation polymerization. The oxidants used were KIO3 and FeCl3 for the polyalkylanilines and polypyrrole (PPy), respectively. Among the polyalkylanilines synthesized with KIO3 salt, the highest conductivity was obtained with poly(2‐ethylaniline) (P2EAn) with a value of 4.10 × 10?5 S/cm. The highest yield was obtained with poly(N‐methylaniline) with a value of 87%. We prepared the conducting composites (PPy/P2EAn and P2EAn/PPy) by changing synthesis order of P2EAn and PPy. The electrically conducting polymers were characterized by IR spectroscopy, ultraviolet–visible spectroscopy, thermogravimetric analysis, and X‐ray diffraction spectroscopy. From the results, we determined that the properties of the composites were dependent on the synthesis order of the polymers. The thermal degradation temperature of PPy was observed to be higher than that of the other polymers and composites. We determined from X‐ray results that the structures of the homopolymers and composites had amorphous regions (88–95%) and crystal regions (5–12%). From the Gouy balance magnetic measurements, we found that the polymers and composites were bipolaron conducting mechanisms. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 241–249, 2006  相似文献   

5.
Two water soluble conjugated polymers, poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and ammonium ion stabilized poly(phenylene vinylene) (P2), are found to be able to reduce noble metal ions to zero-valent metals via a direct chemical deposition technique. Au nanoparticle clusters can be obtained through reduction of Au3+ ions by PEDOT:PSS and the electronic coupling between them can be controlled by HAuCl4 concentration. Core/shell Ag/polymer nanostructures are prepared from reduction of Ag+ ions by P2, which have a ppb detection limit for 4-MBA using surface-enhanced Raman spectroscopy (SERS). This conjugated polymer mediated synthesis of metal nanoparticles may open a new avenue for fabricating nanomaterials and nanocomposites with tunable optical properties that are dominated by their structure and electronic coupling between nanoparticles.  相似文献   

6.
Poly(N‐methylpyrrole) (PNMPy), poly(N‐methylpyrrole‐TiO2) (PNMPy‐TiO2), and poly (N‐methylpyrrole‐ZnO) (PNMPy‐ZnO) nanocomposites were synthesized by in situ electropolymerization for cathode active material of lithium secondary batteries. The charge–discharging behavior of a Li/LiClO4/PNMPy battery was studied and compared with Li/LiClO4/PNMPy‐nanocomposite batteries. The nanocomposites and PNMPy films were characterized by cyclic voltammetry, in situ resistivity measurements, in situ UV–visible, and Fourier transform infra‐red (FTIR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The differences between redox couples (ΔE) were obtained for polymer nanocomposites and PNMPy films. During redox scan, a negative shift of potential was observed for polymer nanocomposite films. Significant differences from in situ resistivity of nanocomposites and PNMPy films were obtained. The in situ UV–visible spectra for PNMPy and polymer nanocomposite films show the intermediate spectroscopic behavior between polymer nanocomposites and PNMPy films. The FTIR peaks of polymer nanocomposite films were found to shift to higher wavelengths in PNMPy films. The SEM and TEM micrographs of nanocomposite films show the presence of nanoparticle in PNMPy backbone clearly. The result suggests that the inorganic semiconductor particles were incorporated in organic conducting PNMPy, which consequently modifies the properties and morphology of the film significantly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41526.  相似文献   

7.
Novel indium tin oxides (ITO)/PEDOT/IrO2 composite electrodes were fabricated by dipping IrO2 colloids onto poly(3,4-ethylenedioxythiophene) (PEDOT)-coated ITO substrate for morphine electrooxidation. Scanning electron microscopy (SEM) image showed that the active IrO2 layer was dispersed more uniformly at PEDOT intermediate layer than at bare ITO substrate. Voltammetric measurements indicated that the as-prepared IrO2 colloids are very active for both the oxygen evolution reactions (OER) and for reversible valance transition between lower and higher oxides. ITO/PEDOT/IrO2 electrodes perform enhanced electrochemical activity towards the oxidation of morphine, as compared with the un-modified ITO-based PEDOT electrodes (ITO/PEDOT) or the ITO electrodes directly coated with IrO2 (ITO/IrO2), suggesting that the composite electrode materials are one of the potential candidates for morphine detection.  相似文献   

8.
Spherical copper nanoparticles (Cu‐NPs) have been immobilized on the compact surface of potentiostatically generated poly(N‐methylpyrrole) (PNMPy) films by applying a reduction potential of −0.60 V to a deionized water solution of CuCl2. Although the number density of Cu‐NPs obtained using this procedure is not high (4·106 cm−2), the average diameter is relatively high (∼50 nm). The surface topology and roughness of films with Cu‐NPs–PNMPy are intermediate between those obtained for as prepared PNMPy and reduced PNMPy. Analysis of the electrochemical properties indicates that Cu‐NPs promote the electroactivity of the PNMPy, this effect being more evident for composited made with the thinnest PNMPy films. In opposition, the electrostability and electrical conductivity are not enhanced by deposited Cu‐NPs. Similar findings are obtained for bilayered PNMPy–Cu‐NPs–PNMPy films. POLYM. COMPOS., 37:594–601, 2016. © 2014 Society of Plastics Engineers  相似文献   

9.
Organic thermoelectric materials based on conducting polymers, especially for polyaniline (PANi) and poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS), have attracted great concern due to their tunable electron transport properties by controlling doping level. Here, the solvent effects of deionized H2O and NH3·H2O were investigated on the electrical conductivity and Seebeck coefficient of PANi/PEDOT/PSS composite films. The introduction of PEDOT/PSS can not only effectively improve the quality of pure PANi film, but also enhance the electrical conductivity of PANi film. The different volumes of deionized H2O as dilution have a great influence on the electrical conductivity of PANi/PEDOT/PSS composite thin film with a maximum electrical conductivity value of 63.5 S cm?1, which is much higher than pure PANi and pristine PEDOT/PSS. The introduction of NH3·H2O shows a positive effect on Seebeck coefficient with a large decline on electrical conductivity of PANi/PEDOT/PSS. The Raman spectroscopy, scanning electron microscopy (SEM), and UV-vis spectroscopy were used to obtain the morphology and structure information of PANi/PEDOT/PSS.  相似文献   

10.
In this article, a series of fluorene/2,5-dithenyl-1H-pyrrole-based electroactive polymers (HS-X) with different feed ratio of SC12F/OF were synthesized via Suzuki coupling reactions. Chemical characterization of polymers was elucidated by 1H NMR and Fourier-transform infrared spectroscopy. Electrochemical and electrophysical characterization of the synthesized polymers were investigated by cyclic voltammetry, UV-vis spectroscopy, and fluorescence spectroscopy. Thermal stability of polymers were studied with differential scanning calorimetry and manipulation of the Tg values of HS-X polymers was managed by increasing the numbers of the spiroalkylated fluorene (SAF) moieties incorporated into the polymer backbone. Five different conjugated polymers (HS-1, HS-2, HS-3, HS-4, and HS-5) were used as hole transport layer material in the fabrication of organic light-emitting diode (OLED) devices. The energy levels of the highest occupied molecular orbital as well as the lowest unoccupied molecular orbital and photoluminescence intensities were independent of the number of SAF units. OLED devices based on HS-X polymers were fabricated according to ITO/PEDOT:PSS/HS-X/Alq3/LiF:Al device configuration. Their electroluminescence performances were investigated and the best performance were obtained with the polymer containing 20% SC12F (HS-4) in an OLED device with a turn on voltage of 11.8 V, a maximum luminance of 1202 cd/m2 and a maximum luminous efficiency of 0.30 cd/A compared to other polymers with different feed ratio.  相似文献   

11.
We showed that it is possible to use sulfonated poly(amic acid)s (SPAA) to template polymerize 3,4-ethylenedioxythiophene (EDOT) to PEDOT, resulting in an aqueous dispersion of conducting polymer. This study compares PEDOT with poly(aniline) (PANi) and poly(pyrrole) PPy using the same and another, more rigid, poly(amic acid) template. A variety of system parameters, including reaction time, conductivity, and overall thermal stability, were noted to change systematically depending on the systems chosen. PANi-SPAA takes less than one tenth of the reaction time of PEDOT-SPAA (12 h versus 7 days), and results in higher conductivities at room temperature (ca. 10 S/cm). However, it is not as thermally stable as the PEDOT-SPAA system; conductivity is not measureable after annealing at 300 °C. PPy-SPAA was found to be more thermally stable than PANi-SPAA (less mass lost at 300 °C), but it was still more conductive than un-doped PEDOT-SPAA by a factor of 1000 (ca. 1.0 S/cm).  相似文献   

12.
Conformational characteristics of poly(lactide)s have been investigated by density functional theory and ab initio molecular orbital (MO) calculations and NMR experiments on model compounds. Characteristic ratios, configurational entropies, and internal energies of poly(L-lactide) and poly(DL-lactide), whose stereosequences were generated by Bernoulli and Markov stochastic processes, were calculated under the refined rotational isomeric state scheme with conformational energies and geometrical parameters derived from the MO calculations. In terms of the conformational characteristics thus revealed, we have elucidated the reason why unperturbed chain dimensions determined experimentally for poly(L-lactide) are scattered considerably and, furthermore, discussed crystallization and crystal structures of poly(L-lactide) and molecular characteristics of poly(DL-lactide) synthesized from rac-lactide with stereospecific polymerization catalysts.  相似文献   

13.
A novel nanocomposites film of conducting polymers including single-walled carbon nanotubes (SWCNTs), polypyrrole (PPy) and gold nanoparticles (AuNPs) modified electrode has been applied in voltammetric sensors to detect epinephrine (EP) sensitively when ascorbic acids (AA) and uric acids (UA) exist. The nanocomposites film of conducting polymers which show an excellent electrocatalystic activity for the oxidation of EP and UA was characterized by scanning electron microscopy (SEM) and electrochemical methods. The catalytic peak currents obtained from differential pulse voltammetry (DPV) increased linearly with increasing EP concentrations in the range of 4.0 × 10−9–1.0 × 10−7 M with a detection limit of 2.0 × 10−9 M (S/N = 3), respectively. The results showed that the nanocomposites of conducting polymers can selectively determine EP in the coexistence of a large amount of UA and AA. In addition, the sensor exhibited excellent sensitivity, selectivity and stability. The PPy/AuNPs/SWCNTs nanocomposites film can also be satisfactorily used for detecting EP in epinephrine hydrochloride injection when contain AA and UA, which also shows good recovery for determination of EP in some biological fluids.  相似文献   

14.
In this study, some kinds of multilayer (double and triple) electrochromic (EC) surfaces were prepared using layer-by-layer (LBL) electrodeposition techniques. Polypyrrole (PPy) was deposited as the first layer and the upper layers were changed. EC characteristics were investigated by spectroelectrochemical measurements. Surface roughness parameters (Root Mean Square-RMS) were determined using atomic force microscopy (AFM) technique. The results showed that different color options may be obtained by altering LBL deposition of EC polymers. Equilibrium water contact angle (ϴequwater) measurements showed that incorporation of hydrophilic poly(3,4-ethylenedioxythiophene) PEDOT in LBL EC surfaces resulted in a decrease in the contact angle. However, the ϴequwater of multilayer films increased with the incorporation of the hydrophobic polycarbazole (PCarb) layer.  相似文献   

15.
π‐Conjugated poly(3‐nitropyridine‐2,5‐diyl) ( PPy‐3‐NO2 ), poly(3,3′‐dinitro‐2,2′‐bipyridine‐5,5′‐diyl) ( PBpy‐3,3′‐diNO2 ), and a poly(arylene ethynylene) type polymer consisting of a 3,3′‐dinitro‐2,2′‐bipyridine unit ( PAE‐1 ) were synthesized by Cu‐promoted Ullmann coupling reaction and Pd‐catalyzed coupling reaction. PPy‐3‐NO2 and PAE‐1 were soluble in organic solvents such as DMSO, DMF, and chloroform, and gel permeation chromatography analysis showed a number average molecular weight (Mn) of 9,300 and 12,300, respectively. PPy‐3‐NO2 gave intrinsic viscosity, [η], of 0.53 dL g?1 in DMF. PBpy‐3,3′‐diNO2 had somewhat lower solubility. The polymers exhibited a UV–vis peak at about 430 nm. PPy‐NO2 received electrochemical reduction at ?1.5 V versus Ag+/Ag in acetonitrile, and gave an electrochemical redox cycle in a range from 0 to ?1.1 V versus Ag+/Ag in an aqueous solution. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1763–1767, 2006  相似文献   

16.
Three new donor–acceptor type poly{2,2l‐(3,4‐ dialkoxythiophene‐2,5‐diyl)bis[5‐(2‐thienyl)‐1,3,4‐oxadiazole]}s ( P1, P2, and P3 ) were synthesized starting from thiodiglycolic acid and diethyl oxalate through multistep reactions. The polymerization was carried out using chemical polymerization technique. The optical and charge‐transporting properties of the polymers were investigated by UV‐visible, fluorescence emission spectroscopic and cyclic voltammetric studies. The polymers showed bluish‐green fluorescence in solutions. The electrochemical band gaps were determined to be 2.03, 2.09, and 2.17 eV for P1 , P2, and P3, respectively. The nonlinear optical properties of new polymers were investigated at 532 nm using single beam Z‐scan and degenerate four‐wave mixing (DFWM) techniques with nanosecond laser pulses. The polymers exhibited strong optical limiting behavior due to “effective” three‐photon absorption. Values of the effective three‐photon absorption ( 3PA ) coefficients, third‐order nonlinear susceptibilities (χ(3)), and figures (F) of merit were calculated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

17.
Conducting polymers are widely used in many biomedical applications, but their non-degradability and non-biocompatibility limit their widespread use in applications. For this reason, many studies have been carried out on the developing degradable, biocompatible, and electrically conductive polymers. In this study, mixtures of conductive polymers (poly(m-antranilic acid) (P3ANA) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)) with biocompatible and biodegradable poly(ε-caprolactone) (PCL) were prepared. Their nanofibers were obtained by electrospinning and their antioxidant properties were investigated by 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid (ABTS) and copper ion reducing antioxidant capacity (CUPRAC) assays. Electrochemical properties were also investigated by cyclic voltammetry and electrochemical impedance spectroscopy. The highest antioxidant activity was obtained from PCL/P3ANA3 electrospun nanofiber containing 10% (of PCL w/w) P3ANA with 93 and 614 μg TE/mg values for ABTS and CUPRAC assays, respectively. This nanofiber was found to be non-toxic according to 2,5-diphenyl-2H-tetrazolium bromide (MTT) analysis. PCL/PEDOT:PSS electrospun nanofiber has the highest maximum anodic current value of 0.08 mA. The maximum anodic current value of PCL/P3ANA3 nanofiber with the highest amount of P3ANA is also higher than other PCL/P3ANA nanofibers. These nanofibers were characterized by FT-IR, UV–vis., XRD and TGA and their surface morphologies were examined by scanning electron microscopy (SEM).  相似文献   

18.
We report an enhancement in the efficiency of organic solar cells via the incorporation of gold (Au) or silver (Ag) nanoparticles (NPs) in the hole-transporting buffer layer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), which was formed on an indium tin oxide (ITO) surface by the spin-coating of PEDOT:PSS-Au or Ag NPs composite solution. The composite solution was synthesized by a simple in situ preparation method which involved the reduction of chloroauric acid (HAuCl4) or silver nitrate (AgNO3) with sodium borohydride (NaBH4) solution in the presence of aqueous PEDOT:PSS media. The NPs were well dispersed in the PEDOT:PSS media and showed a characteristic absorption peak due to the surface plasmon resonance effect. Organic solar cells with the structure of ITO/PEDOT:PSS-Au, Ag NPs/poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM)/LiF/Al exhibited an 8% improvement in their power conversion efficiency mainly due to the enlarged surface roughness of the PEDOT:PSS, which lead to an improvement in the charge collection and ultimately improvements in the short-circuit current density and fill factor.  相似文献   

19.
A high cycling stability material and an additive manufacturing method are reported for the fabrication of solid electrochromic devices. The poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate)/multi‐walled carbon nanotube (PEDOT:PSS/MWCNT) nanocomposites were synthesized via in situ polymerization. A carboxymethyl cellulose gel was used as the ink vehicle for screen printing. The electrochromic (EC) performance of films patterned by screen printing was also examined. The results of characterization indicate that strong interfacial interactions occurred between PEDOT:PSS and the MWCNTs and the MWCNTs formed a network in these conducting polymers film, so the composite was more conductive than pure PEDOT:PSS. Devices containing PEDOT:PSS/MWCNTs were more stable after 1000 cycles, exhibited higher rate of ion exchange and faster increases in current. The composite containing 0.3 wt % MWCNTs also had a 23% higher color contrast (ΔE*) than pure PEDOT:PSS at 2.5 V applied voltages. The EC inks with well printability not only can be used to print large area films, but also can print fine lines and pixel‐type dots in displays. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45943.  相似文献   

20.
The goal of this study is to determine the electrically conductivity of the polymers poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate): N-methyl-2-pyrrolidinone (PEDOT: PSS: NMP) and PEDOT: PSS when blended with polyvinyl alcohol (PVA). While the conducting polymers have high conductivity when not blended with PVA, they are brittle and difficult to spin-coat. Thus, the motivation for this study is to develop blends of these two conducting polymers with PVA to produce a material with optimized mechanical properties and that can also be spin-coated. The blends are produced using aqueous preparations of these materials. Mixtures of various weight percentages (wt %) of PEDOT: PSS: NMP and PEDOT: PSS are prepared and spin-coated on glass slides to form thin films. In the blends, the film conductivity increases with increasing content of either PEDOT: PSS: NMP or PEDOT: PSS. For example, 100 wt % of PEDOT: PSS: NMP and 60 wt % of PEDOT: PSS: NMP blended with PVA exhibit conductivities of, respectively, 10 and 4.02 S/cm. In contrast, conductivities of only 0.0525 and 0.000506 S/cm are observed, respectively, for 100 wt % of PEDOT: PSS and 60 wt % of PEDOT: PSS content in the PEDOT: PSS/PVA blends (No NMP). The addition of the NMP enhances the electrical conductivity by two to five orders of magnitude (depending on the amount of PVA in the blend) due to conformational change of PEDOT chains. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

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