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Article Citation - WoS: 7Citation - Scopus: 7Electrochemical and optical properties of dicyclohexylmethyl substituted poly(3,4-propylenedioxythiophene) analogue(Wiley, 2018) Cakal, Deniz; Cihaner, Atilla; Onal, Ahmet M.An analogue of disubstituted 3,4-propylenedioxythiophenes, namely 3,3-bis(cyclohexylmethyl)-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin (ProDOT-CycHex(2)), was synthesized and its electrochemical polymerization was carried out successfully in an electrolyte solution of 0.1 M tetrabutylammonium hexafluorophosphate dissolved in a mixture of acetonitrile and dichloromethane (3/1: v/v). The corresponding polymer called PProDOT-CycHex(2) has a reduced band gap of 1.85 eV and an electrochromic property: blue/violet when neutralized and highly transparent when oxidized. Also, PProDOT-CycHex(2) film exhibited faster response time (0.7 s) and higher coloration efficiency (769 cm(2)/C) during oxidation when compared to its benzyl substituted analogue. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46214.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 - WoS: 75Citation - Scopus: 80Unique Ligand-Based Oxidative Dna Cleavage by Zinc(ii) Complexes of Hpyramol and Hpyrimol(Wiley-v C H verlag Gmbh, 2007) Maheswari, Palanisamy Uma; Barends, Sharief; Oezalp-Yaman, Seniz; de Hoog, Paul; Casellas, Helene; Teat, Simon J.; Reedijk, JanThe zinc(II) complexes reported here have been synthesised from the ligand 4-methyl-2-N-(2-pyridylmethyl)aminophenol (Hpyramol) with chloride or acetate counterions. All the five complexes have been structurally characterised, and the crystal structures reveal that the ligand Hpyramol gradually undergoes an oxidative dehydrogenation to form the ligand 4-methyl-2-N-(2-pyridylmethylene)aminophenol (Hpyrimol), upon coordination to Zn-II. All the five complexes cleave the phi X174 phage DNA oxidatively and the complexes with fully dehydrogenated pyrimol ligands were found to be more efficient than the complexes with non-dehydrogenated Hpyramol ligands. The DNA cleavage is suggested to be ligand-based, whereas the pure ligands alone do not cleave DNA. The DNA cleavage is strongly suggested to be oxidative, possibly due to the involvement of a non-diffusible phenoxyl radical mechanism. ne enzymatic religation experiments and DNA cleavage in the presence of different radical scavengers further support the oxidative DNA cleavage by the zinc(II) complexes.Article Citation - WoS: 4Citation - Scopus: 4Synthesis of Polyacrylamide-Based Redox Active Cryogel Using Click Chemistry and Investigation of Its Electrochemical Properties(Wiley-v C H verlag Gmbh, 2021) Tonta, Magdalena M.; Sahin, Zeynep M.; Cihaner, Atilla; Yilmaz, Faruk; Gurek, AysegulFerrocene (Fc) functionalization of macroporous polyacrylamide-based cryogel (PAAm-Epx) is achieved by click chemistry. For this purpose, firstly, PAAm-Epx cryogel with azide functionality (PAAm-N-3) is prepared by using acryalmide (AAm) as the monomer and allyl glycidyl ether (AGE) as the co-monomer followed by subsequent ring opening reaction of epoxide ring of AGE in acidic medium. Azide groups of PAAm-N-3 is then modified with ethynyl ferrocene, leading to the redox active cryogel (PAAm-Fc) together with preserving the unique characteristic properties of the virgin PAAm-Epx cryogel. Swelling, mechanical and morphological behaviours of PAAm-Epx, PAAm-N-3 and PAAm-Fc are investigated. Detailed characterization of the PAAm-Fc is carried out by several techniques such as FTIR (Fourier Transform Infrared Spectroscopy), Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), Inductively Coupled Plasma Optical Emmision Spectrometry (ICP-OES, Cyclic (CV), and Differential Pulse Voltammetry (DPV). Electrochemical analysis confirms the electroactivity and the presence of chemically linked ferrocene unit to the cryogel.Article Citation - WoS: 2Citation - Scopus: 3Impedance Spectroscopy of N-Substituted Oligo-Oxyethylene Polypyrrole Films(John Wiley & Sons inc, 2008) Cihaner, Atilla; Onal, Ahmet M.The electrochemical properties of neutral (dedoped) and oxidized (doped) poly(1,11-bis(1,1-pyrrole)-3,6,9-trioxaundecane) (poly-I) film electrodes were investigated using cyclic voltammetry and electrochemical impedance spectroscopy (EIS) techniques. Poly-I was deposited on glassy carbon electrode (GCE) from acetonitrile solution containing 5.0 x 10(-3) M 1,11-bis(1,1-pyrrole)-3,6,9-trioxaundecane (I) and 0.1 M LiClO4 supporting electrolyte. Doped poly-I exhibits a single semicircle in its complex-capacitance plots, indicating a single dominant ion transport process, together with high capacitance values. These features make this polymer film a candidate for an energy storage material. Also, poly-I can be a candidate as a sensory material for the detection of Ag+ based on impedance parameters. (C) 2008 Wiley Periodicals, Inc.Article Citation - WoS: 3Citation - Scopus: 3Spectroelectrochemical Investigation of Nuclease Active Pt(II) Complexes Containing Pyrrole Oxime(Pergamon-elsevier Science Ltd, 2015) Erdogan, Deniz Altunoz; Kayi, Hakan; Ozalp-Yaman, SenizIn this paper, the electrochemical oxidation of three Pt(II) complexes containing pyrrole oxime (HL) having a general formula of [Pt(NH3)Cl(L)] (1), [Pt(L)(2)] (2), and K[PtCl2(L)] (3) has been investigated by in-situ spectroelectrochemistry in dimethylformamide (DMF). An irreversible metal-based oxidation process occurs during the anodic scan for each of the three complexes. The electronic absorption spectral changes indicate that all the three complexes generate similar Pt(IV) compounds and free ligand. Our experimental data is supported by quantum chemistry calculations utilizing density functional theory. In addition, the frontier orbital energy distributions indicate that electron densities are localized on mainly platinum atom. (C) 2015 Elsevier Ltd. All rights reserved.Article Citation - WoS: 22Citation - Scopus: 25Substituent and Heteroatom Effects on the Electrochromic Properties of Similar Systems(Wiley-blackwell, 2012) Icli-Ozkut, Merve; Cihaner, Atilla; Mersini, Jetmire; Onal, Ahmet M.; Cihaner, Atilla; Cihaner, Atilla; Chemical Engineering; Chemical EngineeringElectrochromic polymers called poly(3,4-dihydro-3,3-bis ((naphthalen-1-yl)methyl)-2H-thieno[3,4-b][1,4]dioxepine) (PProDOT-Np-2), poly(3,3-dibenzyl-3,4-dihydro-2H-selenopheno[3,4-b][1,4]dioxepine), and poly(3,3-dibenzyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine) were synthesized electrochemically and the effect of substituents and heteroatoms on the electrochromic properties were investigated for the similar systems. All polymers show electrochromism from a colored state when neutralized to transmissive when oxidized. Although, increasing bulky size (PProDOT-Np-2) causes lower coloration efficiency (CE) as well as lower optical contrast, the replacement of S atom by Se atom resulted in a lower band gap polymer with a higher CE than its thiophene analog. (c) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 50: 615- 621, 2012Article Citation - WoS: 2Citation - Scopus: 2Synthesis, Properties, and Electrochemistry of a Photochromic Compound Based on Dithienylethene and Prodot(Tubitak Scientific & Technological Research Council Turkey, 2015) Algi, Melek Pamuk; Cihaner, Atilla; Algi, FatihThe synthesis, photochromic features, and electrochemistry of a novel material based on dithienylethene (DTE) and 3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepine (didecyl-ProDOT) units are described. It is noteworthy that 1,2-bis (5-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-2-methylthiophen-3-yl)cyclopent-1-ene can be efficiently switched between open and closed states by light in both solution and in the solid poly(methyl metacrylate) (PMMA) matrix. It is also found that the emission of this novel compound can be switched on and off upon irradiation.Article Citation - WoS: 36Citation - Scopus: 42Synthesis, Spectroscopy and Electrochemical Behaviors of Nickel(ii) Complexes With Tetradentate Shiff Bases Derived From 3,5-bu2t<(Pergamon-elsevier Science Ltd, 2005) Kasumov, VT; Özalp-Yaman, S; Tas, ENickel(II) complexes of a series of N,N'-polymethylenebis(3,5-Bu'(2)-salicylaidimine) ligands containing 2,4-di-Bu'(2)-phenol arms, NiLx, were synthesized and their spectroscopic and redox properties were examined. The UV-vis, H-1 NMR spectroscopic and magnetic results indicate that complexes NiL1-NiL4 unlike NiL5 and NiL6 have a square-planar structure in the solid state and in solution. Cyclic voltammograms of NiLx (x= 1-4) complexes displayed two-step oxidation processes. The first oxidation peak potentials of all Ni(II) complexes corresponds to the reversible one-electron oxidation process of the metal center, yielding Ni(III) species. The second oxidation peak of the complexes was assigned as the ligand based oxidation generating a coordinated phenoxyl radical species. (c) 2005 Elsevier B.V. All rights reserved.Article Citation - WoS: 34Citation - Scopus: 35Soluble Alkyl Substituted Poly(3,4-Propylenedioxyselenophene)s: a New Platform for Optoelectronic Materials(Wiley-blackwell, 2011) Atak, Samed; Icli-Ozkut, Merve; Onal, Ahmet M.; Cihaner, AtillaOptical and electrochemical properties of regiosymmetric and soluble alkylenedioxyselenophene-based electrochromic polymers, namely poly(3,3-dibutyl-3,4-dihydro-2H-seleno pheno [3,4-b][1,4]dioxephine) (PProDOS-C(4)), poly(3,3-dihexyl-3,4-dihydro-2H-selenopheno[3,4-b][1,4]dioxephine) (PProDOS-C(6)), and poly(3,3-didecyl-3,4-dihydro-2H-selenopheno[3,4-b][1,4]dioxephine) (PProDOS-C(10)), are highlighted. It is noted that these unique polymers have low bandgaps (1.57-1.65 eV), and they are exceptionally stable under ambient atmospheric conditions. Polymer films retained 82-97% of their electroactivity after 5000 cycles. The percent transmittance of PProDOS-C(n) (n = 4, 6, 10) films found to be between 55 and 59%. Furthermore, these novel soluble PPro-DOS-C(n) polymers showed electrochromic behavior: a color change form pure blue to highly transparent state in a low switching time (1.0 s) during oxidation with high coloration efficiencies (328-864 cm(2) C(-1)) when compared to their thiophene analogues. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 4398-4405, 2011
