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Citation - WoS: 94
Citation - Scopus: 95
A 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, Fatih
A 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.
Citation - WoS: 11
Citation - Scopus: 12
Ag Nanostructures on a Poly(3,4-Ethylenedioxythiophene) Film Prepared With Electrochemical Route: a Controllable Roughened Sers Substrate With High Repeatability and Stability
(Pergamon-elsevier Science Ltd, 2012) Dogan, Uzeyir; Kaya, Murat; Cihaner, Atilla; Volkan, Murvet
A simple, reliable and reproducible one-step electrochemical method for the preparation of surface-enhanced Raman-active polymer-mediated silver nanoparticles (Ag NPs) on planar indium tin oxide (ITO) coated glass substrates was reported. Poly(3,4-ethylenedioxythiophene) (PEDOT) film was used as a support material for dispersing nanostructured silver nanostructures on the surface homogeneously, since 3,4-ethylenedioxythiophene (EDOT) monomer polymerizes regioregularly. The optical properties and morphologies of the silver substrates have been investigated by ultraviolet-visible (UV-vis) spectroscopy and field emission scanning electron microscopy (FE-SEM). The UV-vis and FE-SEM results revealed that the Ag nanostructures separately appeared on the PEDOT coated ITO after reduction. The effect of the thickness of PEDOT polymer film, reduction potential of silver, the concentration of silver ion solution and the amount of silver particle on the polymer film on the SERS response were studied as well as repeatability and temporal stability of prepared substrates. Brilliant cresyl blue (BCB) has been used as Raman probes to evaluate the properties of the new SERS substrates. Signals collected over multiple spots within the same substrate resulted in a relative standard deviation (RSD) of 9.34%, while an RSD of 11.05% was measured in signals collected from different substrates. The SERS-active substrates were robust and stable which lost only 5.71% of initial intensity after 1 month. (C) 2012 Elsevier Ltd. All rights reserved.
Citation - WoS: 7
Citation - Scopus: 9
Pyrrole Coupling Chemistry: Investigation of Electroanalytic, Spectroscopic and Thermal Properties of N-Substituted Poly(bis-Pyrrole) Films
(Royal Soc Chemistry, 2013) Mert, Olcay; Demir, Ayhan S.; Cihaner, Atilla
An etheric member of N-linked polybispyrroles (PolybisPy) based on 1-(3-(2-(2-(3-(1H-pyrrol-1-yl)propoxy)ethoxy)ethoxy)propyl)-1H-pyrrole (1) was electrochemically synthesized for the versatile investigation of its exciting electrochromic and ion receptor properties. It has been fully characterized by electroanalytic, spectroscopic, thermal, and four-probe techniques. It was thereby found that P1 shows strong stability, and a reversible redox process as well as a good electrochromic material property; transparent yellow in the neutral state, light pink in the intermediate state, and blue in the oxidized state. Also, the corresponding polymer (P1) exhibited a selective voltammetric response towards Na+ among the alkali series in an organic medium. Moreover, P1 film was employed for the detection of Ag+ ions in the solution with cyclic voltammetry without precipitants or complexing ligands, and SEM images confirmed the deposition of metallic silver on the film surface. These prominent features also make P1 a good candidate for many practical uses, such as the recovery of metals and ion sensors.
Citation - WoS: 2
Citation - Scopus: 3
Impedance 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.
Citation - WoS: 30
Citation - Scopus: 31
A New Low-Voltage Polymeric Electrochromic
(Elsevier Sci Ltd, 2010) Pamuk, Melek; Tirkes, Seha; Cihaner, Atilla; Algi, Fatih
Design, synthesis, and properties of a novel donor-acceptor-donor type low-voltage-driven green polymeric electrochrome, P1, which is based on 8-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-11-(2,3-dihydrothieno[3,4-b][l,4]dioxin-7-yl)acenaphtho[1,2-b]quinoxaline (1) are highlighted. It is noted that P1 has an ambipolar (n- and p-doping processes) character in 0.1 M tetrabutylammonium hexafluorophosphate/dichloromethame solution and switches to a transmissive blue state upon oxidation. Furthermore, this new polymeric electrochromic candidate exhibits high redox stability, high coloration efficiency and/or contrast ratio, high percent transmittance (%T) and low response time (1.0 s) with a band gap of 1.10 eV-1.25 eV. (C) 2009 Elsevier Ltd. All rights reserved.
Citation - WoS: 5
Citation - Scopus: 6
An Electrochromic Polymer Based on Cyclopenta[2,1-B;3,4 Effect of a Single Atom Alteration on the Electrochemical and Optical Properties of the Polymer Backbone
(Elsevier Science Sa, 2020) Tutuncu, Esra; Varlik, Bengisu; Kesimal, Busra; Cihaner, Atilla; Ozkut, Merve Icli
An electrochromic polymer, namely "poly(2,6-(3,3-didecyl-3,4-dihydro-2H-thieno [3,4-b] [1,4]dioxepin-6-yl)-4,4-dioctyl-4H-cyclopenta[2,1-b;3,4-b']dithiophene)" (P1), was electrochemically synthesized successfully, and its electrochemical and optical properties were investigated. The band gap of the polymer P1 was calculated as 1.77 eV with -5.45 eV Highest Occupied Molecular Orbital (HOMO) and -3.68 eV Lowest Unoccupied Molecular Orbital (LUMO) energy levels. The polymer P1 is bluish purple when neutralized and highly transparent greenish purple when oxidized. This color change was observed around 1.4 s between its redox states and optical contrast ratio was found to be as 49 % and 53 % with 234 cm(2)/C and 239 cm(2)/C coloration efficiencies at 590 nm and 634 nm, respectively. Moreover, the properties of this polymer were compared to its analogues and also during this comparison the effect of alteration of a single atom in the pendant unit was tried to be understood.
Synthesis and Electropolymerization of a Selenophene Based Chemiluminescent Monomer and Its Use in Blood Detection
(Elsevier Sci Ltd, 2025) Balci, Burcu; Cakal, Deniz; Cihaner, Atilla
A new selenophene based trimeric chemiluminescent compound, namely 5,7-di(selenophen-2-yl)-2,3-dihydrothieno[3,4-d]pyridazine-1,4-dione (S2T-Lum), was synthesized in two steps via electron donor-acceptor-donor approach. Its chemiluminescent reaction with hydrogen peroxide was investigated in an alkaline solution in the presence of various catalysts such as different metal ions, hemin and blood samples and the results were compared with its thiophene analogue (T2T-Lum) and luminol. It was found that S2T-Lum was very sensitive to copper(II) and iron(III) ions, and blood samples. Also, it can be easily concluded that S2T-Lum as a new member of luminol type compounds is a potential candidate for the detection of blood findings in forensic science. Furthermore, S2T-Lum has an irreversible oxidation peak at 1.28 V vs Ag/AgCl, which is responsible from its electropolymerization. S2T-Lum was successfully polymerized electrochemically via potentiodynamic electrolysis without cleavage of its chemiluminescent active appendage. To the best of our knowledge, its corresponding polymer PS2T-Lum film is the first member of selenophene based luminol type electroactive polymers.
Citation - WoS: 8
Citation - Scopus: 8
Improvement of Optical Properties and Redox Stability of Poly(3,4-Ethylenedioxythiophene)
(Elsevier Sci Ltd, 2018) Ertan, Salih; Cihaner, Atilla
In order to improve the optical properties and redox stability of poly(3,4-ethylenedioxythiophene) (PEDOT) without changing its electrochemical and electrochromic behaviour, it was supported with alkyl-substituted polyhedral oligomeric silsesquioxane (POSS) cage. The corresponding copolymers were obtained electrochemically via potentiostatic or potentiodynamic methods and compared to the parent homopolymers. Electrochemical polymerization of EDOT and POSS containing EDOT called EDOT-POSS in various monomer feed ratios was performed in an electrolyte solution of 0.1 M TBAPF(6) dissolved in a mixture of dichloromethane and acetonitrile (1/3: v/v). Just as PEDOT, the copolymers represented the similar band gap (1.61 eV), redox and electrochromic behaviors. On the other hand, when compared to the parent PEDOT, the presence of POSS cages in the copolymer backbone improved the redox stability and optical properties of PEDOT such as higher percent transmittance change (65% at 621 nm), higher transparency at oxidized state, lower switching time (similar to 1.0 s) and higher coloration efficiency (463 cm(2)/C for 95% switching) as well as higher electrochemical stability (86% of its electroactivity retains after 1750 cycles under ambient conditions).
Citation - WoS: 8
Citation - Scopus: 8
Electropolymerization and Ion Sensitivity of Chemiluminescent Thienyl Systems
(Pergamon-elsevier Science Ltd, 2009) Asil, Demet; Cihaner, Atilla; Onal, Ahmet M.
Redox driven chemiluminescent (CL) compounds based on thienyl and pyridazine systems, namely 2,3-dihydrothieno(3,4-d)pyridazine-1,4-dione (T-Lum) and 5,7-di-thiophen-2-yl-2,3-dihydrothieno[3,4-d]pyridazine-1,4-dione (TTT-Lum), were synthesized. Soluble compounds both in organic media and basic aqueous solution were found to give CL and electroluminescent (EL) reactions by the treatment of oxidants (H2O2 and KMnO4) and by an external potential pulse on the working electrode, respectively. Furthermore, the CL reaction can be speeded up by Fe3+ ion or blood samples. On the other hand, one of the compounds. TTT-Lum, can be polymerized successfully via electrochemically both in 0.1 M LiClO4/acetonitrile containing 5% of borontrifluoro diethylether (BF3-Et2O) and neat BF3-Et2O solution. The corresponding polymer film (PTTT-Lum) bearing CL units has a very stable and a well-defined reversible redox couple. Also, the electrochromic polymer film has a band gap of 1.74 eV and exhibits EL behavior. (C) 2009 Elsevier Ltd. All rights reserved.
Synthesis and Characterization of a Luminol Based Chemiluminescent Trimeric System
(Springer/plenum Publishers, 2023) Kesimal, Busra; Balci, Burcu; Cakal, Deniz; Onal, Ahmet M.; Cihaner, Atilla
A luminol based chemiluminescent trimeric system, namely 2,3-dihydro-5,8-di(thiophen-2-yl)phthalazine-1,4-dione (T2B-Lum), bearing thiophene rings as donor units and 2,3-dihydrophthalazine-1,4-dione as an acceptor unit was synthesized in two steps via donor-acceptor-donor approach using two different methods. It was found that T2B-Lum emits chemiluminescent light when exposed to H2O2 in a basic medium, and the presence of substituents and the type of aromatic ring bearing chemiluminescent active group have a direct effect on the compound's sensitivity. Among the members of a large family of metal ions, fluorescent and chemiluminescent T2B-Lum exhibited high sensitivity to Cu2+ and Fe3+ ions. Except for other metal cations (silver(I), cadmium(II), cobalt(II), iron(III), lithium(I), magnesium(II), manganese(II), nickel(II), zinc(II)), it has been observed that T2B-Lum is mostly sensitive to copper(II) ions with a detection limit value of 2.2 x 10(- 3) M. On the other hand, T2B-Lum was also found to exhibit a high sensitivity to extremely dilute aqueous solutions (e.g., 1:50.000 dilution) of blood samples, making it a promising candidate for use in forensic applications.

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