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Citation - WoS: 45
Citation - Scopus: 45
An Ambipolar Low Band Gap Material Based on Bodipy and Edot
(Elsevier Science Bv, 2009) Algi, Fatih; Cihaner, Atilla
A novel donor-acceptor type conducting polymer based on BODIPY dye as acceptor and EDOT units as donor parts is synthesized electrochemically. The unique combination of BODIPY and EDOT units provides an ambipolar (n- and p-doping processes) low band gap material (4). This is the first example of p-n junction in an organic pi-conjugated material where BODIPY unit is incorporated directly in the main chain. Furthermore, the polymer film exhibits electrochromic behavior upon p-doping: a color change from light violet (neutral) to indigo (oxidized). (C) 2009 Elsevier B.V. All rights reserved.
Citation - WoS: 24
Citation - Scopus: 25
A 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.
Citation - WoS: 45
Citation - Scopus: 47
An Electroactive Polymeric Material and Its Voltammetric Response Towards Alkali Metal Cations in Neat Water
(Pergamon-elsevier Science Ltd, 2008) Algi, Fatih; Cihaner, Atilla
The syntheses and characterization of a unique system based on thiophene, pyrrole and benzo-15-crown-5 (SNS-Crown) and its corresponding polymer (PSNS-Crown) are reported. Furthermore, selective, clear and reversible voltammetric responses of the conjugated polymer (PSNS-Crown) film towards the alkali series Li+, Na+ and K+ in both neat water and organic media (ethanol) are described. (c) 2008 Elsevier Ltd. All rights reserved.
Citation - WoS: 30
Citation - Scopus: 31
Synthesis and Properties of 4,4-Difluoro (bodipy)-Based Conducting Copolymers
(Elsevier, 2009) Cihaner, Atilla; Algi, Fatih
The 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.
Citation - WoS: 94
Citation - Scopus: 100
A New Soluble Neutral State Black Electrochromic Copolymer Via a Donor-Acceptor Approach
(Elsevier, 2010) Icli, Merve; Pamuk, Melek; Algi, Fatih; Onal, Ahmet M.; Cihaner, Atilla
Two donor-acceptor systems, 2-decyl-4,7-bis(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-2H-benzo[d][1,2,3]triazole (1) and 4,7-bis(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-2,1,3-benzoselenadiazole (2) are explored in order to attain a low bandgap black polymer electrochrome, which is highly difficult to attain due to the complexity of designing such materials. Electrochemical polymerization of 1 and 2 in 1:4 monomer feed ratio was performed in a mixture of acetonitrile and dichloromethane solution containing 0.1 M tetrabutylammonium hexafluorophosphate. It was found that electropolymerization provides a processable neutral state black copolymer, (P(1-co-2)), which absorbs virtually the whole visible spectrum (400-800 nm). (P(1-co-2)) is the first low bandgap (1.45 eV) electropolymerized material, which switches from black color (L = 14.3, a = 0.29, b = 0.35) in the neutral state to transmissive grey (L = 39.2, a = 0.29, b = 0.33) in the oxidized state with 15.3% of the transmittance change at 522 nm. Furthermore, it exhibits excellent operational and/or environmental stability under ambient conditions. (c) 2010 Elsevier B.V. All rights reserved.
Citation - WoS: 143
Citation - Scopus: 157
Donor-Acceptor Polymer Electrochromes With Tunable Colors and Performance
(Amer Chemical Soc, 2010) Icli, Merve; Pamuk, Melek; Algi, Fatih; Onal, Ahmet M.; Cihaner, Atilla
To 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.
Citation - WoS: 143
Citation - Scopus: 149
A Novel Neutral State Green Polymeric Electrochromic With Superior N- and P-Doping Processes: Closer To Red-Blue (rgb) Display Realization
(Wiley-v C H verlag Gmbh, 2008) Cihaner, Atilla; Algi, Fatih
Two donor-acceptor systems, 4,7-di-2-thienyl-2,1,3-benzoselenadiazole (TSeT) and 4,7-di-2,3-dehydrothieno[3,4-b][1,4]dioxin-5yl-2,1,3-benzoselenadiazole (ESeE) are synthesized and electropolymerized to give polymers PTSeT and PESeE, respectively. One of the polymers, PTSeT, is blue-green in the neutral state and soluble, exhibiting a deep-red emission color. The other, PESeE, is the first 2,1,3-benzoselenadiazole-based neutral state green polymer with a narrow bandgap (1.04eV). Furthermore, PESeE has superior and durable n- and p-doping processes. Beyond the stability and the robustness, both of the polymer films exhibit multi-electrochromic behavior.
Citation - WoS: 14
Citation - Scopus: 14
A novel terthienyl based polymer electrochrome with peripheral BODIPY
(Elsevier Sci Ltd, 2012) Algi, Fatih; Cihaner, Atilla
Design, synthesis and electropolymerization of a new hybrid material based on terthienyl system bearing BODIPY appendage are reported. This electrochemically polymerized unique combination readily gives an electrochromic polymer with a narrow optical band gap (1.71 eV). The electrochrome exhibits purple color when neutralized and sky blue color when oxidized in a monomer-free electrolyte solution containing 0.1 M tetrabutylammonium tetrafluoroborate dissolved in acetonitrile. Spectroscopic and electrochemical features of the electroactive polymer electrochrome indicate that it is a promising candidate for electrochromic device and display applications. (C) 2012 Elsevier Ltd. All rights reserved.
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: 65
Citation - Scopus: 67
An Electrochromic and Fluorescent Polymer Based on 1-(1
(Elsevier Science Sa, 2008) Cihaner, Atilla; Algi, Fatih
A 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.

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