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Article Citation - WoS: 94Citation - Scopus: 95A New Conducting Polymer Bearing 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (bodipy) Subunit: Synthesis and Characterization(Pergamon-elsevier Science Ltd, 2008) Cihaner, Atilla; Algi, FatihA new monomer system based on thiophene, pyrrole and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene dye (SNS-BODIPY) was synthesized and its corresponding polymer (PSNS-BODIPY) was obtained via repetitive cycling or constant potential electrolysis in 0.1 M tetrabutylammonium hexafluorophosphate dissolved in dichloromethane. The PSNS-BODIPY film has very stable and well-defined reversible redox couples during p-doping process. Multi-electrochromic polymer film has a band gap of 2.9 eV with two absorption bands in its neutral state at 351 and 525 nm, attributed to the polymer backbone and BODIPY subunits, respectively. The percentage transmittance changes between both states (neutral and oxidized) were found as 12.1% for 351 nm and 17.7% for 525 nm in the visible region as well as 46.2% for 1050 nm in the near-infrared region. Beyond the robustness, the PSNS-BODIPY film has high redox stability (retaining 53.3% of its electroactivity at 351 nm after 2000 switching) with a low response time of 1.0 s. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 25Citation - Scopus: 27A New Processable and Fluorescent Polydithienylpyrrole Electrochrome With Pyrene Appendages(Pergamon-elsevier Science Ltd, 2013) Tirkes, Seha; Mersini, Jetmire; Oztas, Zahide; Algi, Melek Pamuk; Algi, Fatih; Cihaner, AtillaA new hybrid compound, namely 1-(pyren-3-yl)-2,5-di(thiophen-2-yl)-1H-pyrrole (SNS-P), was polymerized via both chemical and electrochemical methods. Chemically obtained soluble polydithienylpyrrole (c-PSNS-P) bearing pyrene appendages is a homogeneous and uniform polymer with a number averaged molecular weight of 15,200 g/mol. The polymer exhibits both multi-electrochromic and fluorescent properties. Upon oxidation, the color of electrochemically obtained polymer (e-PSNS-P) changes from yellowish orange to greenish yellow and to green/blue and finally to blue. In addition, the polymer induces yellowish orange (564 nm) and bright orange emission (613 nm) in solution and solid states, respectively. (C) 2012 Elsevier Ltd. All rights reserved.Article Citation - WoS: 30Citation - Scopus: 31Synthesis and Properties of 4,4-Difluoro (bodipy)-Based Conducting Copolymers(Elsevier, 2009) Cihaner, Atilla; Algi, FatihThe synthesis, characterization and engineering of a novel polymer based on a unique combination of 1,3,5,7-tetramethyl-8-(4-nitro-phenyl)-2,6-bis(2-thienyl)-4,4-difluoroboradiazaindacene and 3,4-ethylenedioxythiophene are highlighted. It was found that the polymer represents an environmentally robust electroactive material bearing high stability, well-defined quasi-reversible redox couple, and fast response time between redox states as well as high coloration efficiency. (c) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 24Citation - Scopus: 25A Novel Conducting Polymer Based on Terthienyl System Bearing Strong Electron-Withdrawing Substituents and Its Electrochromic Device Application(Elsevier Science Sa, 2008) Asil, Demet; Cihaner, Atilla; Algi, Fatih; Onal, Ahmet M.A novel conducting polymer bearing strong electron-withdrawing substituents (EWS) directly attached to the 3,4-positions of the thiophene ring was synthesized by electrochemical polymerization of diethyl 2,5-di(thiophen-2-yl)thiophene-3,4-dicarboxylate (SSS-Diester). The polymer (PSSS-Diester) was characterized by cyclic voltammetry, FT-IR and UV-vis spectroscopy. The polymer has a reversible redox process and demonstrates a stable electrochromic behavior: reddish orange in the neutral state, brown in the intermediate state and green in the oxidized state. Optical density and response time of the dual-type electrochromic device based on PSSS-Diester were found to be 0.23 and 0.6 s at 623 nm, respectively. It is also noteworthy that the device shows good environmental and redox stability (i.e. 94% of the optical activity of the device retained after 500th switch). (c) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 65Citation - Scopus: 67An Electrochromic and Fluorescent Polymer Based on 1-(1(Elsevier Science Sa, 2008) Cihaner, Atilla; Algi, FatihA novel polymer was synthesized by electrochemical polymerization of 1-(1-naphthyl)-2,5-di-2-thienyl-1H-pyrrole (SNS-1-NAPH). The corresponding polymer (PSNS-1-NAPH) was characterized by cyclic voltammetry, FT-IR and UV-vis spectroscopy. The polymer has a very well-defined and reversible redox process in both organic and aqueous solutions. Furthermore, it shows stable electrochromic behavior; yellow in the neutral state, green in the intermediate state and violet in the oxidized state. PSNS-1-NAPH is soluble in common solvents. Although SNS-1-NAPH is almost nonfluorescent, its polymer is a yellow and/or green light emitter. (c) 2007 Elsevier B.V. All rights reserved.Article Citation - WoS: 52Citation - Scopus: 57Members of Cmy Color Space: Cyan and Magenta Colored Polymers Based on Oxadiazole Acceptor Unit(Amer Chemical Soc, 2012) Ozkut, Merve Icli; Algi, Melek Pamuk; Oztas, Zahide; Algi, Fatih; Onal, Ahmet M.; Cihaner, AtillaIn this study, three novel oxadiazole-based polymers were synthesized and their electrochemical and optical properties were investigated. The polymers were found to have both p- and n-type doping properties accompanied by electrochromic response. Two polymer films exhibit cyan and magenta colors, which constitute two legs of CMY color spaces, in their neutral states and they are soluble in common-organic solvents. According to the color mixing theory, all colors in the visible spectrum including black color can be obtained by using these polymers with a yellow colored electrochromic polymer. Among these polymers, the polymer bearing propyledioxythiophene donor units has some superior properties like high stability (it retains 94% of its electroactivity after 2000 cycles), solubility, and high coloration efficiency (230 cm(2)/C), whereas as expected ethylenedioxythiophene containing one has the lowest band gap as 1.08 eV.Article Citation - WoS: 96Citation - Scopus: 99A Processable Rainbow Mimic Fluorescent Polymer and Its Unprecedented Coloration Efficiency in Electrochromic Device(Pergamon-elsevier Science Ltd, 2008) Cihaner, Atilla; Algi, FatihA processable rainbow mimic fluorescent polymer (PSNSF) based on 1-(9H-fluoren-2-yl)-2,5-di(thiophen-2-yl)-1H-pyrrole (SNSF) was synthesized via electrochemical polymerization in a mixture of ethanol and CH2Cl2 solution containing 0.1 M LiClO4. Characterization was carried out using cyclic voltammetry, UV-vis and F-FAR spectroscopic techniques. Also, an electrochromic device based on PSNSF was studied, which exhibits high coloration efficiency (CE), high redox stability (retaining 98.6% of its optical activity after 4000th switch) and very low response time (less than 0.5 s). (c) 2007 Elsevier Ltd. All rights reserved.Article Citation - WoS: 43Citation - Scopus: 45Electrochemical and Optical Properties of New Soluble Dithienylpyrroles Based on Azo Dyes(Pergamon-elsevier Science Ltd, 2009) Cihaner, Atilla; Algi, FatihTwo dithienylpyrroles based on azo dyes, namely 2,5'-dimethyl-[4-(2,5-di-thiophen-2-yl-pyrrol-1-yl)-phenyl]azobenzene (SNS-AB2) and 2,5'- dimethyloxy-[4-(2,5-di-thiophen-2-yl-pyrrol-1-yl)phenyl]azobenzene (SNS-AB3), were synthesized and their corresponding polymers (PSNS-AB2 and PSNS-AB3) were successfully obtained via electropolymerization. The monomers have lower oxidation potentials (0.75 V and 0.80V vs. Ag/AgCl for SNS-AB2 and SNS-AB3, respectively) when compared to their analogous. Both monomers exhibited photoisomerism properties under irradiation at 360 nm. During the irradiation process, for example, the color of SNS-AB3 changes from yellow to greenish yellow. The electroactive polymer films have well defined and reversible redox couples with a good cycle stability in both aqueous and organic solutions. The polymer films also exhibited electrochromic behaviors; color changes from yellowish green to dark green for the PSNS-AB2 (lambda(max) = 435 nm and E-g = 2.31 eV) and from mustard color to green for PSNS-AB3 (lambda(max) = 430nm and E-g = 2.34 eV). Furthermore, the soluble polymers demonstrated different hues of yellow and green colors. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 56Citation - Scopus: 56Processable Electrochromic and Fluorescent Polymers Based on n-substituted Thienylpyrrole(Pergamon-elsevier Science Ltd, 2008) Cihaner, Atilla; Algi, FatihA new series of processable conducting polymers based on thienylpyrrole was synthesized by electrochemical polymerization of 1-(1-naphthyl)-2,5-di(thiophen-2-yl)-1H-pyrrole, 1-(2-naphthyl)-2,5-di(thiophen-2-yl)-1H-pyrrole, 1-(9H-fluoren-2-yl)-2,5-di(thiophen-2-yl)-1H-pyrrole and 1-(benzo-15-crown-5)-2,5-di(thiophen-2-yl)-1H-pyrrole. The corresponding polymers have very well-defined and reversible redox processes in both organic and aqueous solutions. Furthermore, they exhibit multielectrochromic behavior: yellow in the neutral state, green and blue in the intermediate state and violet in the oxidized state. The polymer products are soluble in organic solvents and all of them are fluorescent. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 143Citation - Scopus: 157Donor-Acceptor Polymer Electrochromes With Tunable Colors and Performance(Amer Chemical Soc, 2010) Icli, Merve; Pamuk, Melek; Algi, Fatih; Onal, Ahmet M.; Cihaner, AtillaTo demonstrate the effect of donor (D) and acceptor (A) units on the structure property relationships of electrochromic polymers, design, synthesis, characterization and polymerization of a series of D A type systems, 1-5, based on thiophene, 3,4-ethylenedioxythiophene, and 3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine as D units and 2,1,3-benzoselenadiazole, 2,1,3-benzothiadiazole and 2-decyl-2H-benzo[d][1,2,3]triazole as A units are highlighted. It is found that these units play key roles on the redox behavior, band gap, neutral state color, and the electrochromic performance (stability, optical contrast, coloration efficiency, and switching time) of the system. It is noted that electropolymerization of these D-A systems provides processable low band gap electrochromes, P1-P5, exhibiting high redox stability, coloration efficiency, transmittance and/or contrast ratio and low response time. Furthermore, P1-P5 reflect various hues of blue and green pallets of the RGB color-space in the neutral state. In particular, it is noteworthy that P5 is an excellent blue-to-colorless polymeric electrochrome, which, to our best knowledge, exhibits the highest optical contrast and coloration efficiency among the D A type systems. The panoramic breadth of the neutral state colors and intriguing features of these polymeric materials further confirm that D A approach allows engineering tunable electrochromes, which hold promise for commercialization of polymeric ROB electrochromics.
