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Article Citation - WoS: 14Citation - Scopus: 16Electrosynthesis 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 - Scopus: 1Electrochemical Copolymerization of Thiophene Containing Pseudo-Polyether Cages With Pyrrole(Tubitak Scientific & Technological Research Council Turkey, 2006) Cihaner, Atilla; Onal, Ahmet M.; Chemical EngineeringConducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (1). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)) dissolved in acetonitrile. The spectroelectrochemical properties of the films were investigated using UV-VIS spectroscopy.Article Citation - WoS: 25Citation - Scopus: 26Electrochemical 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: 26Citation - Scopus: 30Electrochemical Polymerization of 9-Fluorenecarboxylic Acid and Its Electrochromic Device Application(Elsevier Science Sa, 2008) Bezgin, Buket; Cihaner, Atilla; Onal, Ahmet M.Poly(9-fluorenecarboxylic acid) (PFCA) was synthesized by electrochemical oxidation of 9-fluorenecarboxylic acid (FCA) using a mixture of nitromethane and boron trifluoride diethyl etherate as the solvent and tetrabutylammonium tetrafluoroborate as the supporting electrolyte. An insoluble and conducting brownish-orange film was deposited on the electrode surface, both during repetitive cycling and constant potential electrolysis at 1.15 V. Characterization of the polymer film has been carried out using Fourier Transform Infrared spectroscopy technique and thermal behavior was studied via thermal gravimetric analysis. Structural analysis showed that the polymerization of FCA occurred at 2,7-position. Spectroelectrochemical behavior of the polymer film on indium tin oxide working electrode was studied by recording the electronic absorption spectra, in-situ, in monomer-free electrolytic solution at different potentials and it is found that the PFCA film can be reversibly cycled between 0.0 V and 1.2 V Furthermore, a dual type electrochromic device based on PFCA was constructed and its spectroelectrochemical properties were investigated. The electrochromic device exhibits color change from transparent to dark blue with a good open circuit memory. (c) 2008 Elsevier B.V. All rights reserved.
