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1.
A novel organic molecule of 9H-carbazole-9-carbothioic methacrylic thioanhydride (CzCS2metac) was synthesized by incorporating CS2 and methacrylate groups into the carbazole monomer structure. CzCS2metac was characterized by FTIR, 1H-NMR and 13C-NMR spectroscopy. CzCS2metac was electropolymerized in 0.1 M tetraethylammonium tetrafluoroborate (TEABF4)/acetonitrile (CH3CN) on glassy carbon electrode (GCE). The characterization of the electrocoated P(CzCS2metac)/CFME thin film was studied by various techniques, such as cyclic voltammetry, scanning electron microscopy–energy-dispersive X-ray analysis and electrochemical impedance spectroscopy. The specific capacitance (C sp) of P(CzCS2metac)/MWCNT/GCE in the scan rate of 20 mV s?1 (C sp = 38.48 F g?1 from area formula, C sp = 38.52 F g?1 from charge formula) was increased ~15.66 and ~15.64 times in area and charge formulas compared to P(CzCS2metac)/GCE (C sp = 2.46 F g?1 from area and charge formulas). The same results were also obtained from Nyquist graphs. The specific capacitance value of composite film (C sp = 1.09 × 10?3 F) is ~15.66 times higher than the polymer film (C sp = 6.92 × 10?5 F). The composite film may be used as supercapacitor electrode material in energy storage devices.  相似文献   

2.
N-Methylpyrrole (N-MPy), 2,2′-bithiophene (BTh), and 3-(Octylthiophene) (OTh) were electrocopolymerized in 0.2 M NaClO4/CH3CN on glassy carbon electrode (GCE). The resulting terpolymers of N-MPy, BTh and OTh in different initial monomer feed ratios such as [N-MPy]0/[BTh]0/[OTh]0 = 1/1/1 and 1/2/5 were characterized by cyclic voltammetry (CV), Fourier-transform infrared attenuated total reflectance spectroscopy (FTIR-ATR), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and electrochemical impedance spectroscopy (EIS). The capacitive behaviors of the modified electrodes were defined via Nyquist, Bode-magnitude, Bode-phase, and Admittance plots. The equivalent circuit model of Rs(C dl1 (R 1 (QR 2 )))(C dl2 R 3 ) was performed to fit the theoretical and experimental data. The low-frequency capacitance (CLF) were obtained from initial monomer concentrations of 50 mM as CLF = ~2.34 × 10?4 mFcm?2 for P(N-MPy), CLF = 5.06 × 10?4 mF cm?2 for P(BTh), CLF = 5.07 m F cm?2 for P(OTh), and CLF = ~3.78 m Fcm?2 for terpolymer for [N-MPy]0/[BTh]0/[OTh]0 = 1/1/1. The terpolymer may be used as energy storage devices.  相似文献   

3.
In this study, 3-(2-Aminoethyl thiophene) (2AET) monomer was electropolymerized on glassy carbon electrode (GCE) using various electrolytes (lithium perchlorate (LiClO4), sodium perchlorate (NaClO4), tetrabutyl ammonium tetra fluoroborate (TBABF4) and tetraethyl ammonium tetra fluoroborate (TEABF4) in acetonitrile (CH3CN) as solvent. Poly(3-(2-aminoethyl thiophene) (P(2AET))/GCE was characterized by cyclic voltammetry (CV), Fourier transform infrared reflectance spectrophotometry (FTIR-ATR), scanning electron microscopy, energy dispersive X-ray analysis (EDX), and electrochemical impedance spectroscopy (EIS) techniques. The electrochemical impedance spectroscopic results were given by Nyquist, Bode-magnitude, Bode-phase, capacitance and admittance plots. The highest low frequency capacitance (C LF) value obtained was 0.65 mF cm?2 in 0.1 M LiClO4/CH3CN for the initial monomer concentration of 1.5 mM. The highest double layer capacitance (C dl = ~0.63 mF cm?2) was obtained in 0.1 M LiClO4/ACN for [2AET]0 = 0.5, 1.0 and 1.5 mM. The maximum phase angles (θ = 76.1o at 26.57 Hz) and conductivity (Y″ = 3.5 mS) were obtained in TEABF4/ACN for [2AET]0 = 0.5 and 1.0 mM, respectively. An equivalent circuit model of R(Q(R(Q(R(CR))))) was simulated for different electrolytes (LiClO4, NaClO4, TBABF4 and TEABF4)/P(2AET)/GCE system. A good fitting was obtained for the calculated experimental and theoretical EIS measurement results. The electroactivity of P(2AET)/GCE opens the possibility of using modified coated electrodes for electrochemical micro-capacitor electrodes and biosensor applications.  相似文献   

4.
In this article, 3-Hexyl thiophene (3HTh) monomer was electrocoated on carbon fiber micro electrode (CFME) to study electrochemical impedance spectroscopic (EIS) analysis. Poly(3HTh)/CFME is characterized by Cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), Scanning electron microscopy-Energy Dispersive X-ray analysis (SEM-EDX), and electrochemical impedance spectroscopy (EIS). The effects of different monomer concentrations (0.5, 1.0 and 1.5 mM) on polymer were reported in 0.1 M tetraethyl ammonium tetrafluoroborate (TEABF4)/acetonitrile (ACN) solution. The highest low frequency capacitance (CLF = 1.394 mF cm?2) was obtained for [3HTh]0 = 0.5 mM. The equivalent circuit model of R(QR(CR)(RW))(CR) was examined for polymer/electrolyte system.  相似文献   

5.
In this study, poly(methyl methacrylate)/p-phenylenediamine-graphene oxide, poly(methyl methacrylate)/graphene, and poly(methyl methacrylate)/graphene oxide nanocomposite series were prepared using simple solution blending technique. In poly(methyl methacrylate)/p-phenylenediamine-graphene oxide series, graphene oxide modified with p-phenylenediamine was used to improve its dispersion and interfacial strength with matrix. Morphology study of poly(methyl methacrylate)/p-phenylenediamine-graphene oxide nanocomposite revealed better dispersion of p-phenylenediamine-graphene oxide flakes and gyroid patterning of poly(methyl methacrylate) over the filler surface. Due to nonconducting nature of graphene oxide, there was no significant variation in the thermal or electrical conductivity of these nanocomposites. Thermal conductivity of poly(methyl methacrylate)/p-phenylenediamine-graphene oxide 1.5 was 1.16 W/mK, while the electrical conductivity was found to be 2.3 × 10?3 S/cm.  相似文献   

6.
Gel polymer electrolytes (GPEs) consist of poly(ethylene oxide) (PEO), sodium iodide (NaI) and different amount of multi-walled carbon nanotubes (MWCNT) were prepared. The conductivity study revealed that the highest ionic conductivity of GPE was 7.02 × 10?3 S cm?1. The structural and complexation between the materials are authenticated via X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. Under the exposure of AM 1.5, the fabricated DSSCs exhibited the highest photoenergy conversion efficiency of 7.23% with a short circuit current density (JSC) of 18.64 mA cm?2, open circuit voltage (VOC) of 0.590 mV and fill factor (FF) of 65.7%.  相似文献   

7.
Poly(lactic acid)/poly(methyl methacrylate) blends containing halloysite nanotube (2 and 5 phr) and epoxidized natural rubber (5–15 phr) were prepared by melt mixing. The impact strength of poly(lactic acid)/poly(methyl methacrylate) blend was slightly improved by the addition of halloysite nanotube. Adding epoxidized natural rubber further increased the impact strength of poly(lactic acid)/poly(methyl methacrylate)/halloysite nanotube nanocomposite. Single Tg of poly(lactic acid)/poly(methyl methacrylate) is observed and this indicates that poly(lactic acid)/poly(methyl methacrylate) blend is miscible. The addition of halloysite nanotube into poly(lactic acid)/poly(methyl methacrylate) slightly increased the Tg of the blends. The epoxidized natural rubber could encapsulate some of the halloysite nanotube and prevent the halloysite nanotube from breaking into shorter length tube during the melt shearing process.  相似文献   

8.
A new blue fluorescent monomer, 9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene, was designed and synthesized in good yield. Its homopolymer poly(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene) (P(ADN)) and soluble conductive vinyl copolymers poly[(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene)‐co‐styrene] (P(ADN‐co‐S)) and poly[(9,10‐di(1‐naphthalenyl)‐2‐vinylanthracene)‐co‐(9‐vinylcarbazole)] (P(ADN‐co‐VK)) were synthesized using free radical solution polymerization. All the polymers showed high glass transition mid‐point temperatures (203 to 237 °C) and good thermal stabilities. The photoluminescence emission of the copolymers was similar to that of P(ADN) (with two maxima at 423 and 442 nm). The lifetimes of P(ADN‐co‐S) (6.82 to 7.91 ns) were all slightly less than that of P(ADN) (8.40 ns). The lifetime of P(ADN‐co‐VK) increased from 7.8 to 8.8 ns with an increase in VK content. The fluorescence quantum yields of P(ADN‐co‐S) showed an overall increasing tendency from 0.42 to 0.58. The quantum efficiencies of P(ADN‐co‐VK) decreased from 0.36 to 0.19 with an increase of VK fraction. With increasing S/VK content, the highest occupied molecular orbital of P(ADN‐co‐S)/P(ADN‐co‐VK) ranged from ?5.58 to ?5.73 eV, which was similar to that of P(ADN) (?5.71 eV). The band gaps of P(ADN‐co‐S) and P(ADN‐co‐VK) were about 2.97 eV, which were equal to that of P(ADN), and smaller than that of 2‐methyl‐9,10‐di(1‐naphthalenyl)anthracene (MADN) (3.04 eV) and poly(9‐vinylcarbazole) (3.54 eV). Preliminary electroluminescence results were obtained for a homojunction device with the configuration ITO/MoO3 (20 nm)/P(ADN)/LiF (1 nm)/Al (100 nm), which achieved only 30–50 cd m?2, due to P(ADN) having a low mobility of 4.7 × 10?8 cm2 V?1 s?1 compared to that of its model compound MADN of 6.5 × 10?4 cm2 V?1 s?1. © 2013 Society of Chemical Industry  相似文献   

9.
A novel monomer, 2,6‐di(thiophene‐2‐yl)‐3,5bis(4‐(thiophene‐2‐yl)phenyl)dithieno[3,2‐b;2',3'‐d]thiophene ( Th4DTT) has been synthesized and used as an electro‐active material. It has been electropolymerized onto glassy carbon (GC) electrode in sodium dodecyl sulfate (SDS) solution (0.1 M) together with multi‐walled carbon nanotubes (MWCNT). A good capacitive characteristics for P(Th4DTT)/MWCNT composite has been obtained by electrochemical impedance spectroscopy (EIS), which is, to our best knowledge, the first report on capacitor behavior of a dithienothiophene. A synergistic effect has been resolved by Nyquist, Bode‐magnitude—phase and admittance plots. Specific capacitance of the conducting polymer/MWCNT, calculated from cyclic voltammogram (CV) together with area and charge formulas, has been found to be 20.17 F g?1. Long‐term stability of the capacitor has also been tested by CV, and the results indicated that, after 500 cycles, the specific capacitance is 87.37% of the initial capacitance. An equivalent circuit model of Rs(C1(R1(Q(R2W))))(C2R3) has been obtained to fit the experimental and theoretical data. The double layer capacitance (Cdl) value of P(Th4DTT)/MWCNT (4.43 mF cm?2) has been found to be 25 times higher than P(Th4DTT) (Cdl= 0.18 mF cm?2). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40061.  相似文献   

10.
Friedel-Crafts acylation and in situ polymerization were adopted to graft polyamide on multi-walled carbon nanotube (MWCNT) surface to form MWCNT-PA using γ-Phenyl-?-caprolactone. Via electrospinning, MWCNT-PA/PAPBI and MWCNT-PA/PAPBI/PANI nanofibers were prepared using MWCNT-PA, poly(azo-pyridine-benzophenone-imide) (PAPBI) and polyaniline (PANI) and DGEBA as matrix. Compared with 3 wt% MWCNT-PA/PAPBI nanofibers (20.2 GPa), tensile modulus for film reinforced with 3 wt% MWCNT-PA/PAPBI/PANI nanofibers (27.6 GPa) was considerably increased. Thermal stability of MWCNT-PA/PAPBI/PANI nanofibers reinforced epoxy was higher with T10 633–654°C and Tg 283–291°C relative to DGEBAMWCNT-PA/PAPBI system. The filler loading also increased the electrical conductivity of DGEBA/MWCNT-PA/PAPBI/PANI from 3.44 to 6.01 S cm?1.  相似文献   

11.
Melt compounding is used to mix ethylene-vinyl acetate copolymer (EVA) and multi-walled carbon nanotube (MWCNT). Then the obtained EVA/MWCNT mixtures were foamed using a chemical blowing agent. Without any modification of MWCNT, a significant improvement of the tensile properties was observed for the EVA/MWCNT foams. With increasing the MWCNT content to 10 phr, the average cell size decreases to 36 µm due to the higher melt viscosity and the average cell density increases to 10.5 × 106 cell/cm3 due the heterogeneous nucleation. To investigate the possible applications for static dissipative purpose, the surface resistivity of EVA/MWCNT foams was also investigated.  相似文献   

12.
A novel poly(crystal violet)/graphene-modified glassy carbon electrode (PCV/Gr/GCE) was fabricated for the simultaneous determination of Pb2+ and Cd2+. The electrochemical behavior of both species at the PCV/Gr/GCE was investigated employing cyclic voltammetry. In acetate buffer, the modified electrode showed an excellent electrocatalytical effect on the oxidation of both species and was further used for their determination. Under optimized analytical conditions, the oxidation peak currents of Pb2+ and Cd2+ obtained by differential pulse voltammetry in pH 4.6 acetate buffer showed a linear relationship with their concentrations in the ranges of 2.00 × 10?8–1.95 × 10?5 mol L?1 and 4.00 × 10?8–5.58 × 10?5 mol L?1, respectively. The developed method has excellent sensitivity, selectivity, reproducibility and has been successfully applied to the determination of Pb2+ and Cd2+ in water samples.  相似文献   

13.
Quaternized poly(vinyl alcohol)/chitosan (QPVA/CS) composite membranes were prepared by solution casting method with AlCl3·6H2O aqueous solution as solvent for CS and glutaraldehyde as a crosslinker. The crystalline, thermal and mechanical properties of the QPVA/CS composite membranes were studied by Fourier transform infrared spectroscopy, X-ray diffractometry, differential scanning calorimetry, thermogravimetry and tensile test measurements, respectively. The composite membranes were immersed in potassium hydroxide aqueous solution to form polymer electrolyte membranes. The alkaline uptake, swelling ratio, ion conductivity and methanol permeability of the electrolyte membranes were studied. The experimental results indicated that aluminum chloride hexahydrate (AlCl3·6H2O) had a positive effect on the mechanical properties of the QPVA/CS composite membrane. The elongation-at-break of this membrane reached the maximum of 401.0%. The alkaline uptake and swelling ratio of the composite membranes decreased. With the addition of 30 wt% AlCl3·6H2O, the composite membrane showed the ion conductivity and methanol permeability of 1.82 × 10?2 S cm?1 and 2.17 × 10?6 cm2 s?1, respectively. These values were higher than those of the membrane with acetic acid as the solvent for CS. The selectivity of the QPVA/CS membrane could reach 8.39 × 103 S s cm?3. This study showed that with AlCl3·6H2O as the solution for CS, the high performance QPVA/CS composite alkaline polymer electrolyte membrane could be prepared.  相似文献   

14.
ABSTRACT

In this study, graphene oxide (GO) was chemically reacted with sodium borohydride (NaBH4) to form reduced graphene oxide (rGO). rGO, Montmorillonite nanoclay, and polyvinylcarbazole (PVK) were used to form a ternary nanocomposite via chemical reaction. These nanocomposite qualities were described via scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy-attenuated transmission reflectance (FTIR-ATR). In addition, these materials were used in supercapacitor device as an active material to test electrochemical performances via cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The rGO/nanoclay/PVK nanocomposite shows significantly improved specific capacitance (Csp = 168.64 Fg?1) compared to that of rGO (Csp = 63.26 Fg?1) at the scan rate of 10 mVs?1 by CV method. The enhanced capacitance results in high power density (P = 5522.6 Wkg?1) and energy density (E = 28.84 Whkg?1) capabilities of the rGO/nanoclay/PVK nanocomposite material. The addition of nanoclay and PVK increased the specific capacitance of rGO material due to a dopant effect for supercapacitor studies. Ragone plots were drawn to observe energy and power density of supercapacitor devices. The Csp of rGO/nanoclay/PVK nanocomposite has only 86.4% of initial capacitance for charge/discharge performances obtained by CV method for 5000 cycles.  相似文献   

15.
Poly(N‐vinyl‐γ‐sodium aminobutyrate‐co‐sodium acrylate) (VSA–SA)/polysulfone (PS) composite membranes were prepared for the separation of CO2. VSA–SA contained secondary amines and carboxylate ions that could act as carriers for CO2. At 20°C and 1.06 atm of feed pressure, a VSA–SA/PS composite membrane displayed a pure CO2 permeation rate of 6.12 × 10?6 cm3(STP)/cm2 s cmHg and a CO2/CH4 ideal selectivity of 524.5. In experiments with a mixed gas of 50 vol % CO2 and 50 vol % CH4, at 20°C and 1.04 atm of feed pressure, the CO2 permeation rate was 9.2 × 10?6 cm3 (STP)/cm2 s cmHg, and the selectivity of CO2/CH4 was 46.8. Crosslinkages with metal ions were effective for increasing the selectivity. Both the selectivity of CO2 over CH4 and the CO2 permeation rate had a maximum against the carrier concentration. The high CO2 permeation rate originated from the facilitated transport mechanism, which was confirmed by Fourier transform infrared with attenuated total reflectance techniques. The performance of the membranes prepared in this work had good stability. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 275–282, 2006  相似文献   

16.
In this study, experimental and numerical studies were performed to investigate the relationship among the functionalization method, weight fraction of MWCNTs, thermal imidization cycle, and mechanical properties of various PAI/MWCNT composite films. Poly(amide‐co‐imide)/multiwalled carbon nanotube composite films were prepared by solution mixing and film casting. The effects of chemical functionalization and weight fraction of multiwalled carbon nanotubes on thermal imidization and mechanical properties were investigated through experimental and numerical studies. The time needed to achieve sufficient thermal imidization was reduced with increasing multiwalled carbon nanotube content when compared with that of a pure poly(amide‐co‐imide) film because multiwalled carbon nanotubes have a higher thermal conductivity than pure poly(amide‐co‐imide) resin. Mechanical properties of pure poly(amide‐co‐imide) and poly(amide‐co‐imide)/multiwalled carbon nanotube composite films were increased with increasing imidization time and were improved significantly in the case of the composite film filled with hydrogen peroxide treated multiwalled carbon nanotubes. Both the tensile strength and strain to failure of the multiwalled carbon nanotube filled poly(amide‐co‐imide) film were increased substantially because multiwalled carbon nanotube dispersion was improved and covalent bonding was formed between multiwalled carbon nanotubes and poly(amide‐co‐imide) molecules. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

17.
The vinyl addition type copolymer poly(butoxymethylene norbornene‐co‐biphenyl oxyhexamethyleneoxymethylene norbornene) (P(BN/BphN)) was synthesized by using bis‐(β‐ketonaphthylimino)nickel(II)/B(C6F5)3 catalytic system. P(BN/BphN) was sulfonated to give sulfonated P(BN/BphN) (SP(BN/BphN)) with concentrated sulfuric acid (98%) as sulfonating agent in a component solvent. The ion exchange capacity (IEC), degree of sulfonation (DS), water uptake, and methanol permeability of the SP(BN/BphN)s were increased with the sulfonated time. The methanol permeability of the SP(BN/BphN) membranes was in the range of 1.8 × 10?7 to 7.5 × 10?7 cm2/s, which were lower than the value 1.3 × 10?6 cm2/s of Nafion®115. The proton conductivity of SP(BN/BphN) membranes increased with the increase of IEC values, temperature, and water uptake. Water uptake of the SP(BN/BphN) membranes was lower than that of Nafion® 115 and leads to low proton conduction. Microscopic phase separation occurred in SP(BN/BphN) membrane and domains containing sulfonic acid groups were investigated by SEM and TEM. SP(BN/BphN) membranes had good mechanical properties, high thermal stability, and excellent oxidative stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

18.
Poly (m-toluidine) (PMT) was formed by successive cyclic voltammetry in a monomer solution containing Triton X-100 (TX-100) at the surface of carbon paste electrode (CPE). Nickel was then incorporated into the polymer by electrodeposition of Ni(II) from NiSO4 acidic solution. The electrochemical behavior of this modified electrode (Ni/PMT(TX-100)/MCPE) was investigated in the electrooxidation of ethylene glycol (EG) using cyclic voltammetry and chronoamperometry techniques. Among the electrodes [Ni/PMT(TX-100)/MCPE, Ni/PMT/MCPE, Ni/MCPE, PMT(TX-100)/MCPE, and CPE] used in this study, Ni/PMT(TX-100)/MCPE showed the most effective catalytic activity. The effects of various parameters such as film thickness, electrodepositing time, TX-100 concentration, MT concentration, and EG concentration were investigated on the electrocatalytic oxidation of EG at the surface of Ni/PMT(TX-100)/MCPE. The catalytic rate constant (k) for EG oxidation was also calculated to be 2.1 × 106 cm3 mol?1 s?1 using a chronoamperometric method.  相似文献   

19.
4-Chloroaniline (4ClAni) in the presence of zinc oxide (ZnO) nanoparticles were prepared by chemical oxidative polymerization in hydrochloric acid solution using Ammonium persulfate as oxidant. The effects of amount of ZnO nanoparticles (1, 1.5, 2, 2.5 and 3 g, respectively) on the properties of products were investigated. The obtained nanocomposites was characterized using XRD, IR, UV–visible, and XPS which confirmed the incorporation of the nanoparticle ZnO in the P(4ClAni) matrix and the maximum interaction occurs for 2 g ZnO loading. The TGA analysis was used to confirm the thermal stability and number of water molecules in each nanocomposites chain unit. Although the incorporation of ZnO nanoparticles reduces the electric conductivity of the P(4ClAni), the resulting nanocomposites still keep high conductivities, ranging between 2.19 × 10?2 and 5.92 × 10?4 S cm?1. Good electrochemical response has been observed for samples of amounts ZnO less than 2 g; the observed redox processes indicate that the polymerization on ZnO nanoparticles produces electroactive polymers. The P(4ClAni) layer adhered well to the ZnO nanoparticles and can be used as practical applications.  相似文献   

20.
P(AN-co-VAc)/Fe2O3 core-shell nanocapsules were synthesized by miniemulsion polymerization and P(AN-co-VAc)/Fe2O3@PEDOT core-shell structure was constituted by oxidative polymerization. Homogeneous nanofibers were obtained from the core-shell nanocapsules. Characterizations were performed by XRD, GPC, UV-vis, and FTIR-ATR. SEM, AFM, and TEM. Molecular weight and Tg of the nanocapsules were effected by the increase in γ-Fe2O3 NPs. Nanofiber resistance (Rnfb) drastically decreased from 2700 to 110 kΩ.cm2 by the inclusion of γ-Fe2O3 NPs into the nanocapsules 8.3 kΩ.cm2 obtained after coating with PEDOT. The electrochemical Impedance results were fitted to models of [R (Q(R (CR)))] and [R (Q(R (QR)))], respectively.  相似文献   

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