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Article Citation - WoS: 27Citation - Scopus: 27Electrochromic performance and ion sensitivity of a terthienyl based fluorescent polymer(Elsevier, 2010) Atilgan, Nurdan; Cihaner, Atilla; Onal, Ahmet M.A novel terthienyl based fluorescent polymer bearing strong electron-withdrawing substituents directly attached to the 3,4-positions of the central thiophene ring was synthesized by electrochemical polymerization of diethyl 2,5-di(3,4-ethylenedioxythiophen-2-yl)thiophene-3,4-dicarboxylate. The corresponding polymer was characterized by cyclic voltammetry, FT-IR and UV-vis spectroscopy. The polymer has a well-defined redox process (E-p,E-1/2 = 0.74 V) and demonstrates a reversible electrochromic behavior; lilac in the neutral state and transparent sky blue in the oxidized state. Also, the polymer had low band gap (E-g = 1.82 eV) and high redox stability (retaining 94.0% of its electro-activity after 500th switch). Moreover, the sensitivity of both the monomer and its polymer towards metal cations was investigated by monitoring the change in the fluorescence intensity. Among various common ions both the monomer and its polymer were found to be selective towards Cu2+ and Cu+ ions by quenching the fluorescence efficiency with a Stern-Volmer constant (K-sv) of (1.4-1.6 x 10(3) M-1) and (1.5-1.8 x 10(2) M-1) for monomer and polymer solutions, respectively. (c) 2010 Elsevier Ltd. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 10Polyhedral Oligomeric Silsesquioxanes Appended Conjugated Soluble Polymers Based on Thieno[3,4-C]pyrrole Acceptor Unit(Pergamon-elsevier Science Ltd, 2021) Cakal, Deniz; Cihaner, Atilla; Onal, Ahmet M.A series of new donor-acceptor-donor type fluorescent molecules incorporating thieno[3,4-c]pyrrole-4,6-dione (TPD) as the acceptor unit were synthesized. TPD acceptor unit was modified with polyhedral oligomeric silsesquioxanes (POSS) cages and integrated with thiophene and alkylenedioxythiophene derivatives (3,4-ethylenedioxythiophene (EDOT) and 3,4-propylenedioxythiophene (ProDOT)) using Stille coupling reaction. The monomers, T-2-POSS, E-2-POSS, and P-2-POSS, were polymerized successfully via electrochemical and chemical polymerization techniques. As a fingerprint of D-A-D monomers, all monomers showed dual band characteristics due to intramolecular charge transfer. Soluble polymers exhibited reversible electrochromic responses electrochemically and chemically with fast switching times and high coloration efficiencies. E-2-POSS and its polymer PE2-POSS exhibited the lowest oxidation potential and band gap values as compared to their thiophene and ProDOT analogs. Also, P-2-POSS and its chemically obtained fluorescent polymer PP2-POSS-C represented high sensitivity towards Fe2+ and Fe3+ ions, which makes them potential candidates to be amenable for use in ion sensing. (C) 2021 Elsevier Ltd. All rights reserved.
