Synthesis and Electropolymerization of 9-tosyl-9H-carbazole, Electrochemical Impedance Spectroscopic Study and Circuit Modelling (original) (raw)

Synthesis and Electropolymerization of 9-(4-vinylbenzyl)-9H-carbazole on Carbon Fiber Microelectrode: Capacitive Behavior of Poly(9-(4-vinylbenzyl)-9H-carbazole)

The synthesis of 9-(4-vinylbenzyl)-9H-carbazole (VBCz) monomer and surface characterizations of thin film coating of poly(9-(4-vinylbenzyl)-9H-carbazole), P(VBCz) homopolymer on carbon fiber microelectrode (CFME) was performed. Coatings of polymer thin films obtained, with different initial monomer concentrations, were characterized by cyclic voltammetry, scanning electron microscopy and Fourier transform infrared reflectance-attenuated total reflection spectroscopy. Different initial monomer concentrations (1, 3, 5, and 10 mM) were electrodeposited in 0.1 M lithium perchlorate/acetonitrile solution. The characterization of the thin polymer films was performed on the surface of carbon fiber, and composition of polymeric structure was proposed. Capacitor behavior of modified CFME was studied by electrochemical impedance spectroscopy. The deposition charge of polymer growth affected the redox parameters of resulting coated CFME.

Capacitive behaviors and Monomer Concentration Effects of Poly(9-benzyl-9H-carbazole) on Carbon Fiber Microelectrode

In this work, 9-benzyl-9H-carbazole (BzCz) monomer was chemically synthesized by a new process. It was electrocoated on carbon fiber microelectrode (CFME) as an active electrode material in 0.1M sodium perchlorate (NaClO4)/ acetonitrile (ACN) solution. The electropolymerization process was successfully performed less amount of 3 mM. The characterization of Poly(BzCz)/CFME thin films was performed by Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR) and Electrochemical impedance spectroscopy (EIS). The effects of monomer concentrations (1, 2, and 3 mM) during the preparation of modified electrodes were examined by EIS. Capacitive behaviors of modified CFMEs were defined via Nyquist, Bode-magnitude and Bode-phase plots. Variation of capacitance values by initial monomer concentration and specific capacitance values are presented. The highest specific capacitance value for a potensiodynamically prepared polymer thin film in the initial monomer concentration of 1 mM with a charge of 4.54 mC cm-2 was obtained about 221.4 μF cm-2. An equivalent circuit model, R(C(R(QR)))(CR), for different concentrations of Poly(BzCz). CFME was proposed and experimental data were simulated to obtain the numerical values of circuit components

Electrochemical impedance spectroscopy of poly[carbazole-co-N-p-tolylsulfonyl pyrrole] on carbon fiber microelectrodes, equivalent circuits for modelling

Polycarbazole (PCz) and copolymerization of carbazole (Cz) and N-p-tolylsulfonyl pyrrole (pTsp), P(Czco- pTsp), thin films have been cyclovoltammetrically coated onto carbon fiber electrodes as an active functionalized microelectrode in sodium perchlorate (NaClO4)/acetonitrile (ACN) medium. The resulting thin films of homopolymer and copolymer were characterised by using Fourier transform infrared reflectance spectroscopy (ATR-FTIR), energy dispersive X-ray (EDX) point analysis, scanning electron microscopy (SEM) and atomic force microscopy (AFM). An electrical impedance study on the prepared electrodes is reported in the present paper under different feed ratios of [pTsp]0/[Cz]0 during electrochemical impedance spectroscopic (EIS) measurements. Specific capacitance (Csp) were calculated, P(Cz-co-pTsp) in feed ratio of [pTsp]0/[Cz]0 = 200 has preserved more capacitive behavior especially at lower frequency (Csp =∼156mFg−1) than polycarbazole (Csp =∼2.1mFg−1. The electrochemical impedance data fitted to three different equivalent models were used to find out numerical values of the proposed components.

Synthesis of 9-(4-nitrophenylsulfonyl)-9H-Carbazole: Comparison of an Impedance Study of Poly[9-(4- nitrophenylsulfonyl)-9H-carbazole] on Gold and Carbon Fiber Microelectrodes

In this study, 9-(4-nitrophenylsulfonyl)-9Hcarbazole (NPhSCz) monomer was chemically synthesized. The monomer characterization was performed by Fourier transform infrared spectroscopy, 1H-NMR, and melting point analysis. Two different electropolymerizations of NPhSCz were studied on a gold microelectrode (Au electrode) and carbon fiber microelectrodes (CFMEs) in a 0.1M sodium perchlorate (NaClO4)/acetonitrile solution. The electropolymerization experiments were done from 1 to 4 mM. The characterizations of two different modified electrodes of poly[9-(4-nitrophenylsulfonyl)-9H-carbazole] [poly(NPhSCz)] were performed by various techniques, including cyclic voltammetry, scanning electron microscopy–energy-dispersive X-ray analysis, and electrochemical impedance spectroscopy (EIS). The effects of the initial monomer concentrations (1, 2, 3, and 4 mM) were examined by EIS. The capacitive behaviors of the modified electrodes were defined via Nyquist, Bode magnitude, Bode phase, and admittance plots. The variation of the low-frequency capacitance (CLF) and double-layer capacitance (Cdl) values are presented at different initial monomer concentrations. Poly(NPhSCz)/CFME was more capacitive (CLF ¼ 6.66 F/cm2 and Cdl  28 mF) than the Au electrode (CLF ¼ 6.53 F/cm2 and Cdl  20 mF). An equivalent circuit model of R[QR(CR)(RW)](CR), (R: Current, Q: Constant phase element, C: Double layer capacitance, W: Warburg impedance), was used to fit the theoretical and experimental data

Synthesis of 2-(9H-Carbazole-9-yl)ethyl Methacrylate: Electrochemical Impedance Spectroscopic Study of Poly(2-(9H-carbazole-9-yl)ethyl methacrylate) on Carbon Fiber

In this contribution, 2-(9H-carbazol-9-yl) ethyl methacrylate (CzEMA) monomer was chemically synthesized. The monomer characterization was performed by FT-IR, 1H-NMR, 13C-NMR, and melting point analysis. The electropolymerization of CzEMA was studied onto carbon fiber microelectrodes (CFMEs) as an active electrode material in 0.1M sodium perchlorate (NaClO4)/ acetonitrile (ACN) solution. The electropolymerization experiments were done from 1 mM to 10 mM. The detailed characterization of the resulting electrocoated Poly (CzEMA)/CFME thin films was studied by various techniques, i.e., cyclic voltammetry (CV), Scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). The effects of initial monomer concentrations (1, 3, 5, and 10 mM) during the preparation of modified electrodes were examined by EIS. Capacitive behaviors of modified CFMEs were defined via Nyquist, Bode-magnitude, and Bode-phase plots. Variation of capacitance values by initial monomer concentration and specific capacitance values are presented. The highest specific capacitance value electrocoated polymer thin film by CV method in the initial monomer concentration of 5 mM with a charge of 52.74 mC was obtained about 424.1 lF cm 2.

Copolymer formation of 9-(2-(benzyloxy)ethyl)-9H-carbazole and 1-tosyl-1H-pyrrole coated on glassy carbon electrode and electrochemical impedance spectroscopy

In this work, 9-(2-(benzyloxy)ethyl)-9H-carbazole (BzOCz) and 1-tosyl-1H-pyrrole (TsP) monomers were chemically synthesized and characterized by Fourier transform infrared reflectance (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. BzOCz and TsP were electrocoated on glassy carbon electrode (GCE) in various molar fractions (XTsP00.5, 0.83, 0.91, and 0.98) in 0.1 M sodium perchlorate/acetonitrile. The detailed characterization of poly (BzOCz-co-TsP) was studied by cyclic voltammetry, FTIRattenuated total reflection spectroscopy and electrochemical impedance spectroscopy (EIS). The effects of different molar fractions during the preparation of modified electrodes were studied by EIS technique. The AC impedance technique was used to determine the capacitive behaviors of modified GCE via Nyquist, Bode magnitude, and Bode phase plots. The highest low frequency capacitance value was obtained as CLF023.94 μF cm−2 for XTsP00.98. Therefore, synthesized copolymer has more capacitive behavior than its homopolymers, such as CLF07.5 μF cm−2 for poly(BzOCz) and CLF0 9.44 μF cm−2 for poly(TsP). In order to interpret the AC impedance spectra, R(Q(RW)) electrical equivalent circuit was employed with linearKramers–Kronig test. A mechanism for electropolymerization has been proposed for copolymer formation.

A Comparative Study of Redox Parameters and Electrochemical Impedance Spectroscopy of Polycarbazole Derivatives on Carbon Fiber Microelectrode

In this study, N-Carbazole and its derivatives (N-Vinylcarbazole, N-Ethylcarbazole, N-Vinylbenzylcarbazole, and N-Benzylcarbazole) were electrochemically polymerized on carbon fiber microelectrodes (diameter ~7 μm) by cyclic voltammetry within a potential range from 0.0 to 1.4 V. Redox parameters, Scanning electron microscopic (SEM) images were determined and also capacitance behaviors of polymers were examined via electrochemical impedance spectroscopy (EIS). EIS measurements of polycarbazole derivatives were given comparatively. The existence of a capacitance behavior is shown by Nyquist, Bode magnitude, Bode-phase, Admittance plots relationship. Although the highest low frequency capacitance (CLF=12901 μA cm-2) and maximum phase angle of 81.9 o at a frequency of 1 Hz were obtained for N-Vinylbenzylcarbazole, the lowest anodic and cathodic potential difference (ΔE=0.04 V) and double layer capacitance (Cdl=0.11 μA cm-2) were indicated in 0.1 M LiClO4/PC.

A novel synthesis of 4-toluene 9H-carbazole-9-carbodithioate, electropolymerization and impedance study

eXPRESS Polymer Letters

Among conducting polymers, polycarbazoles are known for their good electro-activity [1, 2] and thermal , electrical , photo-physical , and electrochromic properties . They have been suggested for a number of applications, such as electroluminescent devices [9], sensors , redox catalysts , and electrochromic displays . The functional groups, such as amino, imino and sulfonic groups have been performed for achieving new polymers which meet the criteria of commercial applications . There are many novel syntheses of functional polycarbazole papers. 3,6bis (2,3-dihydrothieno [3,4- N-(o-ethynyl)phenylynamides and arylynamides [24] and 9-(4-nitrophenylsulfonyl)-9H-carbazole were given in literature. The synthesis was per-480 Abstract. A novel synthesis of 4-toluene 9H-carbazole-9-carbodithioate (TCzC) was chemically synthesized and characterized by Fourier Transform Infrared (FTIR), proton nuclear magnetic resonance ( 1 H-NMR), and carbon nuclear magnetic resonance ( 13 C-NMR) spectroscopies. Specific (C sp ) and double layer capacitances (C dl ) of the electro-coated poly(carbazole) and poly(TCzC) films were obtained on glassy carbon electrode (GCE) by impedimetric method with DC potential from -0.1 to +1.0 V by increasing potential of 0.2 V. The polymers were characterized by Cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), Atomic force microscopy (AFM), and Electrochemical impedance spectroscopy (EIS). The use of additional variable (DC potential) helped to disambiguate the equivalent circuit model of R(C(R(Q(RW))))(CR). Simulation results were compared with experimental data. In this study, substituted group effects of CS 2 and tosyl on carbazole polymer were investigated by EIS technique. CS 2 group together with tosyl group in the structure of carbazole decreased the specific capacitance value (C sp = 0.43 mF·cm -2 ) compared to PCz (C sp = 1.44 mF·cm -2 ). Electropolymerization formation was seriously affected by substituted groups of CS 2 and tosyl on conjugation system because of the electron donor and acceptor ability.

Electrochemical impedance of poly(9-tosyl-9H-carbazole-co-pyrrole) electrocoated carbon fiber

In this paper, copolymer of 9-tosyl-9H-carbazole (TCz) and pyrrole (Py) comonomers were electrochemically deposited onto carbon fiber micro electrode (CFME) as an active electrode material. An electrochemical impedance study on the prepared electrodes is reported. Poly(TCz-co-Py)/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). Capacitive behaviors of modified CFMEs were defined via Nyquist, Bode-magnitude and Bode-phase plots. An examination is made of which equivalent circuits of R(C(R(Q(RW)))) and R(C(R(Q(RW))))(CR) used for modeling the system. The effect of monomer ratio (mole fraction, XTCz = nTCz/nTCz + nPy) on the formation of copolymer is reported in 0.1M sodium perchlorate (NaClO4)/acetonitrile (ACN) solution. The inclusion of TCz in the copolymer structure was also confirmed by FTIR-ATR, SEM, and CV measurements. The highest low frequency capacitance (CLF = 22.7 for R(C(R(Q(RW)))) and CLF = 22.6mFcm−2 for R(C(R(Q(RW))))(CR)) were obtained for XTCz = 0.91.

Capacitive behavior of polycarbazole- and poly (N-vinylcarbazole)-coated carbon fiber microelectrodes in various solutions

The electrochemical behavior of polycarbazole (PCz) and poly(N-vinyl carbazole) P(NVCz) was investigated by means of electrochemical impedance spectroscopy (EIS). Supporting electrolytes made from various combinations of solvents (acetonitrile and propylene carbonate) and salts (sodium perchlorate, lithium perchlorate, and tetraethyl ammonium perchlorate) were employed in the investigation. Information on the double layer capacitance (Cdl) and specific capacitance (Csp) of P(NVCz) was achieved by cyclic voltammetry (CV), chronoamperometry and chronopotentiometry. Carbon fiber microelectrodes (CFME) were electrocoated by cyclic voltammetry in a monomer-free solution and displayed film thicknesses in the range *200 nm to *4.8 lm. The capacitive behavior of the PCz- and P(NVCz)-coated carbon fiber microelectrodes was also investigated by CV. The effects of the type of electrolyte and solvent on the electrochemical impedance spectroscopic data were subsequently fitted with an ((R(C(R(Q(RW))))(CR))-equivalent circuit model to calculate the numerical values of the proposed components. The obtained experimental Csp values for PCz/CFME and P(NVCz)/CFME, as measured in LiClO4/ACN, were 280.5 mF g-1 and 294.1 mF g-1, respectively.