Search Results

Now showing 1 - 3 of 3
  • Article
    Citation - WoS: 14
    Citation - Scopus: 16
    Electrosynthesis of Polyfuran in Acetonitrile-Boron Trifluoride-Ethyl Ether Mixture and Its Device Application
    (John Wiley & Sons inc, 2007) Tirkes, Seha; Onal, Ahmet M.
    Electrochemical polymerization of furan was achieved in acetonitrile/boron trifluoride/ethyl ether (CH3 CN/BF3/EE) mixture in the presence of tetrabutylammonium tetrafluoroborate via constant potential electrolysis at 1.4 V versus Ag/AgCl. Electrochemical behavior of furan was investigated in the same solvent mixture of varying ratios, utilizing cyclic voltammetry. Free-standing polyfuran (PFu) films were obtained in CH3CN/BF3/EE mixture (2/4/4; v/v/v) and characterized using FTIR spectroscopic technique. Spectroelectrochemical behavior of the PFu film was investigated by recording the electronic absorption spectra, in sitn, in monomer-free solution. It is observed that PFu film can be reversibly cycled between -0.1 V (gray) and + 0.6 V versus Ag-wire (gray color); however, this behavior diminishes in the presence of water. Electrochromic device application of PFu film with poly(ethylene dioxythiophene) was also studied. (c) 2006 Wiley Periodicals, Inc.
  • Article
    Citation - WoS: 25
    Citation - Scopus: 26
    Electrochemical Synthesis of Poly(3-Bromo and Its Device Application
    (Elsevier Science Sa, 2007) Cihaner, Atilla; Onal, Ahmet M.
    A functionalized thiophene containing both an electron withdrawing and an electron donating group, 3-bromo-4-methoxythiophene (BrMeOTh) was succesfully polymerized in acetonitrile containing 0.1 M tetrabutylammonium tetrafluoroborate (TBABF4) electrolyte via electrochemical oxidation of the corresponding monomer. BrMeOTh exhibits a lower oxidation potential (1.68 V vs Ag/AgCl) than thiophene (2.05 V vs Ag/AgCl). Spectroelectrochemical properties of poly(3-bromo-4-methoxythiophene) (PBrMeOTh) was investigated in situ recording the electronic absorption spectra of the polymer film coated on indium-tin oxide (ITO) at various potentials. The maximum transmittance difference between the oxidized and reduced states was measured as 39.2% and the time required to attain 90% of the total transmittance difference was found to be 1.2 s. Both cyclic voltammetric and spectroelectrochemical studies showed that the polymer exhibit a lower oxidation potential, a relatively narrow band gap, a stable conducting state and a higher degree of electrochemical reversibility. It is also found that, as synthesized PBrMeOTh films possess a linear structure along the polymer backbone. Moreover, dual type electrochromic device of PBrMeOTh with poly(3,4-diethylenedioxythiohene) (PEDOT) was constructed and its spectroelectrochemical, electrochromic switching and open circuit stability were investigated. Dual electrochromic device showed a good optical contrast and distinctive color changes with the ability of good switching times (1.1 s) under atmospheric pressure. (c) 2006 Elsevier B.V. All rights reserved.
  • Article
    Citation - WoS: 11
    Citation - Scopus: 14
    Electrochemical Synthesis of New Conducting Copolymers Containing Pseudo-Polyether Cages With Pyrrole
    (Elsevier Science Sa, 2007) Cihaner, Atilla
    Conducting copolymers have been synthesized via electrochemical oxidation of pyrrole (Py) in the presence of monomer 1, 11 -bis(1,1-pyrrole)-3,6,9-trioxaundecane (I) in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)) dissolved in acetonitrile. It is observed that reversible redox behavior of poly(I-co-Py)s shifts to more positive potentials with the increasing amount of I in the comonomer mixture, indicating formation of a copolymer. It is also found that increasing the ratio of I in the comonomer mixture decreases the conductivity of the obtained polymer films. The dark electrical conductivity measurements in the temperature range of 300-100 K revealed the extrinsic type of conduction with activation energy values being in the range of 82.3-16.9 meV. (c) 2007 Elsevier B.V. All rights reserved.