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Öğe A New Strategy for Photo-Electrochemical Reduction of Carbon Dioxide Using a Carbazole-BODIPY Based Metal-Free Catalyst(Wiley-V C H Verlag Gmbh, 2024) Ozdemir, Mucahit; Ulucay, Sude; Altinisik, Sinem; Koksoy, Baybars; Yalcin, Bahattin; Koyuncu, SermetIn this study, a cross-linked boron dipyrromethene (BODIPY) photocatalyst containing a carbazole donor group designed for photoelectrocatalytic carbon dioxide (CO2) reduction is synthesized and characterized. The BODIPY-based system, coated onto a platinum surface, is evaluated for its electrochemical and photocatalytic performance under light illumination. Cyclic voltammetry (CV) and chronoamperometry measurements reveals enhanced photocurrent responses, confirming the catalyst's ability to effectively drive CO2 reduction. Gas chromatography/mass spectrometry (GC-MS) analysis identifies the formation of ethanol (C2H5OH) as a major reaction product, showing that its yield increased with extended reaction times. Additionally, the photocatalyst demonstrates remarkable performance with significantly increasing turnover numbers (TON) and turnover frequencies (TOF) over time, indicating stable and sustained catalytic activity. With a Faradaic efficiency of 34.79% at a potential of -1.15 V, this BODIPY system exhibits both high activity and long-term stability. The combination of efficient electron transfer and visible light absorption by the carbazole-BODIPY donor-acceptor structure positions this system as a highly promising candidate for sustainable CO2 conversion applications.Öğe A new water-soluble naphthalene diimide as a highly selective fluorescent chemosensor for Cu(II) ion: Synthesis, DFT calculations, photophysical and electrochemical properties(Elsevier Science Sa, 2024) Abourajab, Arwa; Karsili, Pelin; Rashid, Rebwar; Dinleyici, Meltem; Pasaogullari, Nur; Altinisik, Sinem; Koyuncu, SermetThe highly selective, sensitive, and water-soluble fluorescent sensors are desideratum for optoelectronic, environmental, biological, and biomedical applications. An innovative fluorescence chemosensor, naphthalene diimide (3) with metal binding sites, was designed, synthesized and characterized. The chemosensor's optical, electrochemical, spectroelectrochemical, and morphological properties were investigated, and then the density functional theory (DFT) simulations were conducted. The selectivity of 3 for the metals Cu(II), Ag(I), Hg(II), Mg (II), Fe(III), Ca(II), Co(II), Zn(II), Pb(II) and Cd(II) were investigated through UV-visible and fluorescence spectroscopy techniques. 3 was highly selective and sensitive toward Cu(II) metal ions. The chemosensor can detect Cu(II) in water with a detection limit of 1.11 mu M, which is lower than the WHO standard and has good repeatability. Further investigations through the IR, DPV, AFM, UV-visible and fluorescence spectroscopies, SEM, EDX and TEM techniques confirmed the binding capabilities of the 3 with Cu(II).Öğe Aggregation-induced red-shift emission from self-assembled planar naphthalene diimide dye: Interlayer in a Schottky-type photodiode and DFT studies(Elsevier, 2024) Karsili, Pelin; Abourajab, Arwa; Dinleyici, Meltem; Altinisik, Sinem; Koyuncu, Sermet; Dolek, Gamze; Kus, MahmutIn this study, a planar, soluble, thin film-forming and self-assembled small naphthalene diimide (3) molecule with a subtle moiety at the imide-nitrogen was synthesized, and applied for the first time in literature as an interfacial layer between Al and p-Si layers in a Schottky-type photodiode. The morphology of the compound was examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thin film structure and morphology affected the optical and electrical properties. The energy levels of the highest occupied molecular orbitals and lowest unoccupied molecular orbitals of 3 were calculated as -6.14 eV and -4.02 eV, corresponding to the band gap of 2.12 eV consistent with density functional theory (DFT) results. Differential scanning calorimetry (DSC) studies revealed a relatively high Tg value at 208 degrees C, indicating high-temperature applicability of the crystalline structure. The I-V measurements of Al/3/p-Si heterostructure were performed under dark and various light power intensities. The current steadily rose with each incremental 20 mW increase in light intensity. The reverse current increased almost 10-fold at 100 mW/cm2 illumination compared to dark measurement. The photodiode's responsivity, photosensitivity, and detectivity factors were elucidated. The photodiode's characteristic values, such as Io, n, phi b, and Rs, were obtained as 3.50 x 10-6 A, 8.24, 0.588 eV and 2.266 k Omega, respectively. The fabricated Schottky-type diode showed promising results for the optoelectronic field. The compound's perfect solubilities in a wide range of solvents, processability, excellent chemical and photochemical stabilities, and exciting optical, thermal and electrochemical properties make it an ideal candidate for thin film and molecular electronics applications.Öğe Black-to-Transmissive Electrochromic Switching PEDOT-co-poly(N-ethylcarbazole) via a Sustainable and Facile In Situ Photo(co)polymerization Method(Amer Chemical Soc, 2024) Tabak, Tugberk; Altinisik, Sinem; Ulucay, Sude; Koyuncu, Sermet; Kaya, KeremIt is a great challenge to obtain black-to-transmissive switches using one type of polymer. Therefore, the color blending/mixing theory has been previously applied by many research groups to produce black-to-transmissive materials (BTMs) through the (electro)chemical copolymerization of several monomers. However, these (electro)chemical copolymerization methods exhibited numerous drawbacks in terms of sustainability. In this work, for the first time, the synthesis of an electrically conductive (bromide-doped) poly(3,4-ethylenedioxythiophene)-poly(N-ethylcarbazole) (PEDOT-co-PECz) copolymer was demonstrated using an in situ and sustainable photopolymerization technique. Spectrally and microscopically characterized copolymers were then deposited onto ITO/glass using spray coating. The copolymer film demonstrated to switch from a black state (L*: 38.16; a: -0.33; b: -2.89) to a transmissive state (L* = 83, a* = -3, b* = -6) with a contrast of 31.6% Delta T at 650 nm in fast response times (2.28-4.38 s). The results highlight the importance of this advanced method for the sustainable and fast fabrication of smart windows.Öğe Boosting Photocatalytic Metal-Free Hydrogen Production of Viologen-Based Covalent Organic Frameworks(Amer Chemical Soc, 2024) Altinisik, Sinem; Yildiz, Gizem; Patir, Imren Hatay; Koyuncu, SermetIn the pursuit of efficient and sustainable methods for photocatalytic hydrogen generation from water, covalent organic frameworks (COFs) have risen to prominence. Serving as a crucial link between organic flexibility and synthetic tunability, COFs present themselves as highly promising candidates for visible light-driven hydrogen production. Herein, we demonstrated that donor-acceptor (D-A) type viologen-derived COF containing 1,4-bismethylbenzene linker (COF-MB-TPCBP) as a noble metal-free catalyst could achieve a high hydrogen production rate of up to 4 mmol g(-1) h(-1) under visible light irradiation. Moreover, the adsorption of COF-MB-TPCBP onto the TiO2 semiconductor surface has led to an approximate 1.35-fold enhancement in efficiency value. This strategy could contribute to the development of innovative, metal-free COFs for hydrogen evolution through solar energy conversion by refining the associated structure.Öğe Comparative Study of Electrochromic Supercapacitor Electrodes Based on PEDOT:PSS/ITO Fabricated via Spray and Electrospray Methods(Amer Chemical Soc, 2024) Catoglu, Fahri; Altinisik, Sinem; Koyuncu, SermetPEDOT:PSS stands out as a leading commercial conducting polymer due to its excellent water dispersibility, controllable miscibility, adjustable conductivity, and ability to form films through various techniques. This study investigates the electrochemical and electrochromic performance of electrodes prepared by depositing PEDOT:PSS onto ITO surfaces by using two distinct methods: conventional spray coating and electrospray deposition. Detailed characterization of the prepared electrodes was performed by using atomic force microscopy, scanning electron microscopy, Fourier-transform infrared, and Raman spectroscopy techniques. Our findings reveal that electrodes fabricated via electrospray deposition (PEDOT:PSS/ITO electrode_2) significantly outperform those made by spray coating (PEDOT:PSS/ITO electrode_1). Specifically, electrode_2 exhibits a capacitance of 1678.60 mu F cm-2, compared to 826.14 mu F cm-2 for electrode_1, at a current density of 10 mu A cm-2. PEDOT:PSS electrodes exhibit areal energy densities of 0.41 and 0.84 mW h cm-2, along with power densities of 4.96 and 4.97 mu W cm-2, respectively. Moreover, electrode_2 demonstrates a high coloration efficiency of 84.32 cm2 C-1 and fast response times of 1.36 s for coloration and 0.98 s for bleaching. This study highlights the advantages of electrospray deposition over traditional methods, showcasing the potential of electrospray-prepared PEDOT:PSS electrodes for use in multifunctional energy storage devices.Öğe Enhanced Photocatalytic Hydrogen Evolution by Star-Shaped Viologen-Sensitized TiO2 Nanoparticles(Amer Chemical Soc, 2023) Turgut, Kubra; Altinisik, Sinem; Yanalak, Gizem; Koyuncu, Sermet; Hatay Patir, ImrenViologens are well-suited for serving as electron-transfer mediators in redox systems due to their low reduction potential and ability to form stable radical cations. Because of this feature, viologens can play a key role in modifying semiconductors toward enhanced photocatalytic performance. Herein, a series of hybrid photocatalysts composed of TiO2 nanoparticles and star-shaped viologen derivatives with different alkyl chains [TPCBP-X_TiO2; X: ethyl (E), butyl (B), hexyl (H) and octyl (O)] were prepared for the photocatalytic hydrogen evolution from water under visible-light irradiation. The TPCBP-X molecules not only provide photosensitization of TiO2 nanoparticles in the visible-light region but also act as an efficient electron-transfer mediator for the transfer of photoinduced electrons to TiO2 and Pt. Among these photocatalysts, TPCBP-E_TiO2 exhibited a 1.013 mmol g(-1) h(-1) H-2 evolution rate with an apparent quantum yield (AQY) of 20.15% (470 nm), which dramatically improved hydrogen evolution activity among the other structures [TPCBP-X_TiO2 (X; B, H, O)] due to the more porous and uniform surface, resulting in its low barrier effect for electron transfer. In addition, in the presence of a Pt cocatalyst, TPCBP-E_TiO2 yielded a H-2 evolution rate of 17.7 mmol g(-1), which is about 2.2 times higher than that of pure TPCBP-E_TiO2 (8.1 mmol g(-1)) after 8 h of visible-light illumination.Öğe From Plant Oils to High-Performance Supercapacitor Electrode: Poly(guaiazulene) via Photopolymerization(Wiley, 2024) Ermis, Sena; Altinisik, Sinem; Catoglu, Fahri; Yagci, Yusuf; Sari, Erdem; Jockusch, Steffen; Koyuncu, SermetDue to the increasing global demand for electrical energy, the fabrication of advanced energy storage devices, such as supercapacitors (SCs), with outstanding performance is of paramount importance. Herein, the facile light-induced synthesis of a conjugated conductive polymer, namely, poly(guaiazulene) (PGz) is reported on, using a naturally available, low-cost monomer, guaiazulene (Gz). PGz and PGz_rGO (obtained by combining PGz with reduced graphene oxide (rGO)) exhibited high-performance supercapacitor (SC) electrode properties, including remarkable specific capacitance (52.75 F g-1 at 0.24 A g-1 and 258.6 F g-1 at 5.00 A g-1, respectively), excellent cycling stability (97.1% and 94.0% stability after 5000 cycles), high power density (95.5 and 2118.8 W kg-1), and, most importantly, high energy density (5.81 and 30.57 Wh kg-1). These superior features are attributed to the hierarchical porous nature and high electrical/ionic conductivities of the photochemically obtained PGz. Contrary to previous techniques that require harsh reaction conditions, such as carbonization and coupling reactions, the reported photopolymerization involves solely the irradiation of an ethyl acetate solution of a Gz-organic photoinitiator (2-bromoacetophenone) mixture. The photochemical synthesis described here provides a powerful method to produce a sustainable and high-performance SC electrode material, offering a great alternative to commercial SCs. Light-induced synthesis of a conjugated conductive polymer, namely, poly(guaiazulene) (PGz) possessing superior supercapacitor electrode performance is achieved by a sustainable method involving solely the UV-A irradiation of ethyl acetate solution of guaiazulene (a naturally occurring monomer) and an organic photoinitiator, phenacyl bromide. The reported method offers a sustainable alternative to commercial carbon-based supercapacitors. imageÖğe New metallophthalocyanines including benzylphenoxy groups and investigation of their organic-field effect transistor (OFET) features(Elsevier Sci Ltd, 2022) Ozdemir, Mucahit; Altinisik, Sinem; Koksoy, Baybars; Canimkurbey, Betul; Koyuncu, Sermet; Durmus, Mahmut; Bulut, MustafaIn this study, metal and metal-free novel phthalocyanines containing peripheral and non-peripheral tetra 2-ben-zylphenoxy groups were synthesized. The compounds were characterized by UV-Vis, FT-IR, H-1 NMR, and MALDI-TOF mass spectrometry as well as elemental analysis. These new phthalocyanines exhibited excellent solubility in most organic solvents, and their redox behavior was investigated in different solvents such as dimethyl sulfoxide (DMSO) and dichloromethane (DCM). The redox behavior of the peripheral and non-peripheral phthalocyanine compounds 1a -c and 2a -c was determined by cyclic voltammetry and in situ spec-troelectrochemistry. According to organic field-effect transistors (OFETs) measurements, the peripheral and non-peripheral phthalocyanine-cobalt complexes which have higher mobility than others were utilized top-gate bottom-contact OFETs fabrication. The output characteristics of the device show that its mobility is approximately 5 x 10(-2) cm(2)/Vs with p-type accumulation.Öğe Optimization of bioethanol production from sugar beet processing by-product molasses using response surface methodology(Springer Heidelberg, 2024) Altinisik, Sinem; Nigiz, Filiz Ugur; Gurdal, Savas; Yilmaz, Kadir; Tuncel, Necati Baris; Koyuncu, SermetBioethanol production from renewable biomass sources has garnered significant interest due to its potential as a sustainable alternative to fossil fuels. In this study, we investigated the optimization of bioethanol production from molasses, a by-product of the sugar production process using Saccharomyces cerevisiae through Response Surface Methodology (RSM). Initially, the fermentation process was optimized using RSM, considering four independent variables: substrate concentration, pH, temperature, and fermentation time. Subsequently, the effects of these variables on bioethanol yield were evaluated, and a quadratic model was developed to predict the optimum conditions. Analysis of variance (ANOVA) indicated a high coefficient of determination (R2) for the model, suggesting its adequacy for prediction. The optimized conditions for bioethanol production were determined as follows: substrate concentration of 200 g L-1, pH of 5.0, temperature of 30 degrees C and fermentation time of 72 h. Under these conditions, the predicted bioethanol yield was 84%. Overall, this study demonstrates the successful application of RSM for optimizing bioethanol production from molasses using S. cerevisiae, highlighting its potential as a promising feedstock for biofuel production.Öğe PEG-functionalized carbazole-based polymers for UV-protected hydrophilic glass coatings(Elsevier Science Sa, 2023) Altinisik, Sinem; Kortun, Arzu; Nazli, Ahmet; Cengiz, Ugur; Koyuncu, SermetThe UV-absorbing and non-fogging glass coatings containing carbazole-based conjugated backbone with different lengths of hydrophilic PEG subunit (KP-PEG) were produced. The characterizations of the polymers were carried out by using different techniques such as FT-IR, 1H NMR, GPC, TGA and DSC. Transmittance and thin-film morphology analyses, which are essential for UV protection and wettability, were investigated by UV-Vis absorption, AFM and TEM techniques, respectively. Transparent thin films prepared by the polymer solutions in chloroform were obtained by spin coating method at a scan rate of 2000 rpm. The wettability performance and antifogging properties of these surfaces were investigated depending on the PEG length in the polymer subunit. The water contact angle of the surfaces was improved to the range between 60 degrees and 29 degrees depending on the amount of PEG group. KP-PEG750 is the best polymer thin film in terms of having the highest roughness, optimum UV absorption and the low contact angle value.Öğe Photoinduced step-growth polymerizations of thiophene-carbazole based covalent organic polymer(Elsevier Sci Ltd, 2023) Celiker, Tugba; Altinisik, Sinem; Yagci, Yusuf; Koyuncu, SermetA novel metal-free photochemical method for the synthesis of porous conjugated polymers was used to inves-tigate the effects of introducing thiophene co-monomer to the carbazole-based polymer, 4,4 '-bis(3,6-di(thiophen-2-yl)-9H-carbazol-9-yl)-1,1 '-biphenyl (CBP-Th), in terms of its structural, optical, electrochemical and morphological properties. Irradiation of a CBP-Th monomer solution led to the formation of a dark-colored polymer, PCBP-Th, and the role of thiophene on polymerization was investigated, involving electron transfer between CBP-Th and the iodonium ion in the exciplex produced by proton release and radical coupling reactions. The UV-Vis spectra broadened and redshifted due to the elongation of conjugation and solid-state pi-pi in-teractions by extra thiophene additive after the polymerization process. The addition of thiophene co-monomer also resulted in decreasing the onset potentials and thus slightly raised HOMO positions determined by the DPV technique. In theoretical calculations, it has been observed that the charge distribution of PCBP-Th at HOMO is over the entire conjugated structure and it has localization in thiophene-thiophene bridges at LUMO. Since the thiophene co-monomer changes the intermolecular distance, the thermal stability of PCBP-Th polymers de-creases and accordingly increases the amorphous characters. According to AFM, TEM and SEM images, intro-ducing the thiophene co-monomer led to the formation of larger clusters, resulting in a more pronounced surface texture on both the powders and thin films.Öğe Reactive Extraction of Betaine from Sugarbeet Processing Byproducts(Amer Chemical Soc, 2023) Altinisik, Sinem; Zeidan, Hani; Yilmaz, M. Deniz; Marti, Mustafa E.Betaine from natural sources is still preferred over its synthetic analogue in secondary industries. It is currently obtained by expensive separation means, which is one of the main reasons for its high cost. In this study, reactive extraction of betaine from sugarbeet industry byproducts, that is, molasses and vinasse, was investigated. Dinonylnaphthalenedisulfonic acid (DNNDSA) was used as the extraction agent, and the initial concentration of betaine in the aqueous solutions of byproducts was adjusted to 0.1 M. Although maximum efficiencies were obtained at unadjusted pH values (pH 6, 5, and 6 for aqueous betaine, molasses, and vinasse solutions, respectively), the effect of aqueous pH on betaine extraction was negligible in the range of 2-12. The possible reaction mechanisms between betaine and DNNDSA under acidic, neutral, and basic conditions were discussed. Increasing the extractant concentration significantly increased (especially in the range of 0.1-0.4 M) the yields, and temperature positively (but slightly) affected betaine extraction. The highest extraction efficiencies (similar to 71.5, 71, and 67.5% in a single step for aqueous betaine, vinasse, and molasses solutions, respectively) were obtained with toluene as an organic phase solvent, and it was followed by dimethyl phthalate, 1-octanol, or methyl isobutyl ketone, indicating that the efficiency increased with decreasing polarity. Recoveries from pure betaine solutions were higher (especially at higher pH values and [DNNDSA] < 0.5 M) than those from vinasse and molasses solutions, indicating the adverse influence of byproduct constituents; however, the lower yields were not due to sucrose. Stripping was affected by the type of organic phase solvent, and a significant amount (66-91% in single step) of betaine in the organic phase was transferred to the second aqueous phase using NaOH as the stripping agent. Reactive extraction has a great potential for use in betaine recovery due to its high efficiency, simplicity, low energy demand, and cost.Öğe Sequential and Simultaneous Photoinduced Radical and Step- Growth Polymerizations of Carbazole Functional Styrene(Amer Chemical Soc, 2022) Celiker, Tugba; Altinisik, Sinem; Vaitusionak, Aliaksei; Kostjuk, Sergei V.; Koyuncu, Sermet; Yagci, YusufPhotoinduced radical and step-growth polymerizations of carbazole functional styrene (vinyl phenyl carbazole, VPC) by sequential and one-pot strategies have been investigated. The obtained polymers were characterized by FTIR, H-1-NMR, GPC, UV-Vis, PL, CV, and BET analyses. The theoretical charge distribution and HOMO-LUMO calculation by DFT were well-matched with those obtained from optical and electrochemical measurements. In the sequential approach, visible light-induced free-radical photopolymerization of VPC by using bisacyl phosphineoxide results in the formation of linear polymers with side-chain carbazole moieties. The resulting polymers exhibit a smooth surface as a consequence of decreasing crystallinity. As evidenced by TEM analysis, the subsequent photoiniated step-growth polymerization of the carbazole groups by using diphenyliodonium hexafluorophosphate (DPI) yields hyperbranched and cross-linked polymers with the microspheres on the surface. In the one-pot approach, concomitant photoinitiated free-radical and step-growth polymerizations by using DPI results in the formation of cross-linked polymers with dispersed distribution. The total nitrogen uptake of VPC-based polymers by using Brunauer-Emmett-Teller (BET) surface area was found to be between about 150 and 190 m(2)/g at 77 K.Öğe Solar light driven photochromic membranes with viologen additives in PVDF/PVP matrix(Frontiers Media Sa, 2024) Tohtayeva, Jahan; Altinisik, Sinem; Akgun, Mert; Nigiz, Filiz Ugur; Koyuncu, SermetThis study explores the synthesis and characterization of photochromic Polyvinylidenefluoride/Polyvinylpyrrolidone (PVDF/PVP)-based membranes, prepared through an in situ thiol-ene click reaction by incorporating viologen derivatives with different counter ions. Viologens are well-known for their light-sensitive properties and ability to change color, making them useful in various optoelectronic applications. The membranes developed in this study exhibit significant improvements in their interactions with light as a result of improved morphology and enhanced ionic conductivity (approximate to 4 x 10-4 S cm-1) with higher porosity (Ra: 11.26-33.76 nm) compared to conventionally prepared membranes. These membranes show the ability to block almost all ultraviolet (UV) and a 90% of visible light after irradiation. Thanks to these properties, the membranes undergo visible color changes when exposed to sunlight, making them suitable for photochromic and thermochromic applications. The findings of this study could contribute to the development of innovative coating materials that enhance energy efficiency, potentially being applied to buildings, automotive windows, and other surfaces.Öğe Tetra-Carbazole based electroactive donor-acceptor dyes: Effect of the phenyl bridging unit on the electrochromic performance(Elsevier Sci Ltd, 2022) Doyranli, Ceylan; Altinisik, Sinem; Ozdemir, Mucahit; Koyuncu, SermetIn this study, a new Donor-Acceptor-Donor (D-A-D) electroactive molecules (HCQM1 and HCQM2) containing 9H-carbazole and 9-phenyl-9H-carbazole as donor along with quinoxaline (HQ) as acceptor were synthesized and then coated on Indium Tin Oxide/Glass (ITO/Glass) surface by the electrochemical oxidation process. The HOMO-LUMO band gap values obtained by electrochemical oxidation and reduction onsets were calculated as 2.64 and 2.68 eV, respectively. On the other hand, UV-Vis absorption measurements showed that the charge transfer band of HCQM1 was detected at 500 nm with 50 nm red shift upon compared with the HCQM2. According to AFM results, it is seen that the roughness of the poly(HCQM2) film is higher than the poly(HCQM1) film. Finally, the polymer film of HCQM2 showed multi-electrochromic color change (yellow, green, and dark blue) upon the oxidation process. When the electrochromic performance of the HCQM1 and HCQM2 polymer films was compared, it was discovered that the HCQM2 with phenylene spacer unit has better stability and a higher percentage transmittance change (& UDelta;T%) between neutral and oxidized states.Öğe Tuning the Electrochromic Properties of Fluorinated Benzochalcogenodiazole Based Donor-Acceptor Polymers(Wiley-V C H Verlag Gmbh, 2020) Colak, Betul; Altinisik, Sinem; Koyuncu, Fatma Baycan; Canimkurbey, Betul; Koyuncu, SermetIn this study, a series of benzochalcogenodiazole based donor acceptor monomers namely 4,7-bis(4-hexyl-2-thienyl)-2,1,3-benzothiadiazole (TST), 5,6-difluoro-4,7-bis(4-hexyl-2-thienyl)-2,1,3-benzothiadiazole (TST2) and 4,7-bis(4-hexyl-2-thienyl)-2,1,3-benzoselenadiazole (TSeT) were synthesized by Stille reaction and then directly polymerized on to Indium Tin Oxide coated glass (ITO/Glass) surface by electrochemical polymerization process. According to UV-Vis measurements, a 20 nm blue shift was detected at low energy band after fluorination of TST (TST2). Besides, a 40 nm red shift was observed by changing S to Se on the benzochalcogenodiazole moiety (TSeT). Thus, the optical band gaps were varied as 2.32, 2.45 and 2.16 eV for TST, TST2 and TSeT, respectively. According to AFM results, rougher surface was observed in the PTSeT thin film than that of PTST and PTST2. Thin films of electrodeposited polymers onto ITO/glass surface displayed ambipolar multi-electrochromic behavior both anodic and cathodic region. The ambipolar charge distribution was also observed in the theoretical DFT calculations. When the electrochromic performance of the polymer films was compared to each other, it was seen that the PTST2 has a better stability and higher the percentage transmittance change (Delta T%) at near-IR regime between neutral and oxidized states.
