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Article Polysulfur Copolymer as a Support Material for the Preparation of a Novel Multifunctional Photocatalytic Composite Material(Springer, 2025) Kesimal, Busra; Guner, Zuhal Vanli; Cihaner, Atilla; Kaya, MuratOne-step addition of magnetic nanoparticles and titanium dioxide nanoparticles into polysulfur copolymer as cheap and available support was reported for the first time to prepare the magnetically separable heterogeneous catalyst, PolyS-MNP-TiO2. The photocatalytic activities of the PolyS-MNP-TiO2 composite material and its constituents were examined in the methylene blue (MB) degradation, textile-based wastewater simulant, exposed to solar light. Detailed characterization of the catalysts was performed with SEM, TEM, and EDX measurements. The photocatalytic activity of the resulting composite was figured out in the removal of methylene blue dye by using a solar simulator. Significantly, the as-prepared PolyS-MNP-TiO2 exhibits exceptional photocatalytic activity and total degradation of dye molecules was achieved in 60 min. Additionally, the prepared novel photocatalyst showed enhanced stability and reusability due to the magnetic behavior of the composite material and the same portion of catalyst was used in five successive tries without apparent loss in catalytic activity by eliminating long and work-loaded processes like filtration and centrifugation.Article Citation - WoS: 30Citation - Scopus: 32Effect of Fluorine Substituted Benzothiadiazole on Electro-Optical Properties of Donor-Acceptor Type Monomers and Their Polymers(Elsevier Sci Ltd, 2020) Cakal, Deniz; Ercan, Yunus Emre; Onal, Ahmet M.; Cihaner, AtillaA series of trimeric monomers bearing thiophene donor units and fluorinated analogues of benzothiadiazole acceptor units was synthesized via donor-acceptor-donor approach and polymerized electrochemically in order to investigate the effect of fluorine atom on electro-optical properties of both monomers and their corresponding polymers. All monomers exhibited solvatochromic and fluorescent properties. The introduction of fluorine atom into the conjugated backbone increased the oxidation potentials. Upon moving from nonfluorinated to fully fluorinated analogues, the oxidation potential shifts anodically from 1.30 V to 1.7 V. As in the case of monomers, the fluorine atom substitution also resulted in a decrease in the HOMO energy level of the corresponding polymers, leading to an increase in the electrochemical band gap energy (1.71-1.97 eV). This result can be attributed to deviations from planarity and also to decrease in the effective conjugation length. The polymeric film also exhibited electrochromic properties under various external potentials. Switching time and coloration efficiency values decreased with increasing number of fluorine atom substitution.Article Citation - WoS: 18Citation - Scopus: 19Effect of Furan, Thiophene and Selenophene Donor Groups on Benzoselenadiazole Based Donor-Acceptor Systems(Elsevier Science Sa, 2016) Karabay, Lutfiye Canan; Karabay, Bads; Karakoy, Merve Serife; Cihaner, AtillaA series of the monomers called 4,7-di(furan-2-yl)benzo[c][1,2,5]selenadiazole (OSeO), 4,7-di(thiophen-2-yl)benzo[c]11,2,5]selenadiazole (SSeS) and 4,7-di(selenophen-2-yl)benzo[c][1,2,5]selenadiazole (SeSeSe) was synthesized via a donor-acceptor-donor (D-A-D) approach. Benzoselenadiazole was used as an acceptor unit and furan, thiophene and selenophene were used as donor units. The effects of chalcogen atoms (0, S, and Se) in furan, thiophene and selenophene were investigated systematically on the properties of the monomers and their corresponding polymers (POSeO, PSSeS and PSeSeSe, respectively), which were polymerized electrochemically via potentiodynamic or potentiostatic methods. The monomers OSeO, SSeS and SeSeSe exhibited low oxidation potentials of 1.15, 1.25 and 1.19 V vs. Ag/AgCl, respectively. Intramolecular charge transfer interaction between donor and acceptor units was demonstrated from the emission spectra of the monomers. Also, the optical studies showed that the ambipolar and electrochromic polymers POSeO, PSSeS and PSeSeSe have low band gaps of 1.57, 1.47 and 1.45 eV, respectively. (C) 2016 Elsevier B.V. All rights reserved.Article Citation - WoS: 7Citation - Scopus: 6Side Chain Effect on the Electrochemical and Optical Properties of Thieno[3,4-c]pyrrole-4,6-dione Based Donor-Acceptor Donor Type Monomers and Polymers(Royal Soc Chemistry, 2023) Cakal, Deniz; Arabaci, Elif Demir; Yildirim, Erol; Cihaner, Atilla; Onal, Ahmet M.In organic pi-conjugated materials, side chains play great roles that impact far beyond solubility. In this work, we mainly focused on the synthesis of new donor-acceptor-donor (D-A-D) type conjugated monomers and their corresponding polymers appending thieno[3,4-c]pyrrole-4,6-dione (TPD) acceptor with a new side chain, fluorene (Fl), to investigate the side chain effect. In this context, to reveal the precise effect of the side chains on the optical and electrochemical properties of the monomers and polymers synthesized in this work, four series of D-A-D monomers, each containing a TPD core unit with a different side chain, are compared and discussed in relation to each other. Notably, it was discovered that the TPD acceptor unit can be modified with any functional group other than common alkyl chains to impart new functionalities by maintaining their superior optoelectronic properties. New types of side chains can be used to tune the physical characteristics, such as solubility, absorption, emission, and molecular packing. In this work, Fl-appended monomers as a new class of D-A-D type pi-conjugated molecules containing 3,4-ethylenedioxythiophene (EDOT (E)) and 3,4-propylenedioxythiophene (ProDOT (P)) donor units were studied and it was found that 1,3-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-5-(9H-fluoren-2-yl)-4H-thieno[3,4-c]pyrrole-4,6(5H)-dione (E(Fl)) and 1,3-bis(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-5-(9H-fluoren-2-yl)-4H-thieno[3,4-c]pyrrole-4,6(5H)-dione (P(Fl)) exhibited reasonable quantum yields and their corresponding polymers revealed ambipolar character with slightly lower band gap as compared to the previous analogues containing other side chains. Observed experimental results were elucidated by first principle calculations. In this paper, we discussed that using side chain engineering is an effective strategy for improving next-generation organic pi-conjugated materials with the desired properties.Article Citation - WoS: 20Citation - Scopus: 22Electrochemical and Optical Properties of an Azo Dye Based Conducting Copolymer(Tubitak Scientific & Technological Research Council Turkey, 2009) Cihaner, Atilla; Algi, FatihThe electrochemical and optical properties of a novel conducting copolymer called poly(2,5'-dimethyl-[4-(2,5-di-thiophen-2-yl-pyrrol-1-yl)-phenyl]azobenzene-co-(3,4-ethylenedioxythiophene)) (poly(1-co-EDOT)) are reported. Electrochemically synthesized poly(1-co-EDOT) based on the azo dye has a well-defined and reversible redox couple (0.37 V vs. Ag/AgCl) with good cycle stability. The copolymer film exhibits high conductivity (13 S/cm) as well as electrochromic behavior (magenta when neutralized and transmissive sky blue when oxidized). Furthermore, electro-optically active copolymer film has a low band gap of 1.79 eV with a pi-pi* transition at 555 nm.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: 5Citation - Scopus: 5Designing a Solution Processable Poly(3,4-Ethylenedioxyselenophene) Analogue(Amer Chemical Soc, 2018) Ertan, Salih; Cihaner, AtillaA new derivative (EDOS-POSS) of 3,4-ethylenedioxyselenophene integrated with alkyl-substituted polyhedral oligomeric silsesquioxane (POSS) cage was synthesized and characterized. The electroactive monomer was successfully polymerized via both chemical and electrochemical methods. The obtained polymer called PEDOS-POSS was solution-processable and soluble in common organic solvents like tetrahydrofuran, toluene, dichloromethane, and chloroform. PEDOS-POSS polymer exhibited electrochromic behavior: pure blue when neutralized and highly transparent when oxidized. When compared to the parent PEDOS (1.40 eV with lambda(max) = 673 nm), PEDOS-POSS polymer film has a somewhat higher band gap (1.50 eV with lambda(max) = 668 and 724 nm). Also, PEDOS POSS exhibited high optical contrast ratio (59%) and coloration efficiency (593 cm(2)/C for 95% switching) with a low switching time (0.7 s) due to the presence of POSS cage in the polymer backbone. In addition, PEDOS-POSS polymer film was highly robust and stable under ambient conditions (without purging the electrolyte solution with inert gas). Polymer films demonstrated high electrochemical stability; for example, it retained 76% of its electroactivity after 5000 cycles. Furthermore, the polymers exhibited fluorescent properties and exhibited a reddish orange emission centered about at 640 nm. Based on the findings, to the best of our knowledge, it can be concluded that the polymers are the first examples of soluble and fluorescent PEDOS derivatives. These promising properties make PEDOS-POSS polymer a potential material for bioapplications like imaging the cancer cells as well as optoelectronic applications.Article Citation - WoS: 21Citation - Scopus: 21Synthesis and Properties of a Novel Redox Driven Chemiluminescent Material Built on a Terthienyl System(Pergamon-elsevier Science Ltd, 2009) Atilgan, Nurdan; Algi, Fatih; Onal, Ahmet M.; Cihaner, AtillaA novel redox driven chemiluminescent material built on a terthienyl system, namely 5,7-di-ethylenedioxythiophen-2-yl-2,3-dihydro-thieno[3,4-d]pyridazine-1,4-dione (ETE-Lum), which is soluble in both organic media and basic aqueous solution was synthesized and characterized. Furthermore, its polymer, PETE-Lum, which is one of the most rare examples of chemiluminescent polymeric materials bearing a pyridazine unit, was obtained successfully by electrochemical means. Both of the materials give chemiluminescence either by treatment with oxidants (H2O2 and/or KMnO4) or by the application of a potential pulse. (C) 2009 Elsevier Ltd. All rights reserved.Article Citation - WoS: 30Citation - Scopus: 31A New Low-Voltage Polymeric Electrochromic(Elsevier Sci Ltd, 2010) Pamuk, Melek; Tirkes, Seha; Cihaner, Atilla; Algi, FatihDesign, 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.Article Citation - WoS: 5Citation - Scopus: 6An 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 IcliAn 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.
