Novel electrochromic copolymers based on 3-3′-dibromo-2-2′-bithiophene and 3,4 ethylene dioxythiophene

A novel electrochromic material of poly(3-3?-dibromo-2-2?-bithiophene) (P(DBT)) and new electrochromic copolymers of 3,4-ethylenedioxythiophene and 3-3?-dibromo-2-2?-bithiophene prepared from different monomer feed ratios were synthesized by using electroanalytical methods. Homopolymerization and copolymerization were achieved in the medium of 0.1 M LiClO4/ACN solvent-electrolyte couple. Cyclic voltammetry (CV), atomic force microscopy (AFM), fourier transform infrared spectroscopy and ultraviolet and visible (UV-Vis) absorption spectroscopy were used to characterize corresponding homopolymer and copolymers. Electrochemical, morphological and optical properties of copolymers were alternated depending on changing the monomer feed ratio in the copolymer structure. Furthermore, electrochromic properties of the all polymers were also investigated. © 2017 Elsevier Lt

Çok fonksiyonlu yeni polifloren sentezi & donör akseptör tipi polifloren türevleri.

Explosive materials have always been attracting the attention of scientists. Various explosives either in pure bulk form or as admixtures are synthesized and investigated from different points of view. However, because of dangerous character of these materials, their syntheses and properties have to be forecasted by theoretical studies. The new research trends of explosive materials generally include the designs of novel derivatives of well–known explosives to improve their detonation performances (heats of explosion, detonation velocities and detonation pressures) and thermal stabilities and decrease their sensitivities towards friction, electric spark, shock and impact either experimentally or theoretically. NTO (5–nitro–2,4–dihydro–3H–1,2,4–triazol–3–one) and PATO (3–picrylamino–1,2,4–triazole) are very important secondary explosives that take place in the literature for many years in terms of their explosive properties. In this thesis study, new species of these explosives have been designed to enhance their detonation performances (ballistic properties) and to lower their sensitivities and reactivities computationally. Additionally, aromatic nitration reactions and their mechanisms for unprotonated and protonated PATO species have been analyzed. The ab initio quantum chemistry methods, Hartree–Fock (HF) and Density Functional Theory (DFT), have been used in the calculations with Pople basis sets. Novel NTO and PATO tautomeric species have been designed and investigated to enlighten the effects of tautomerism on their quantum chemical properties and detonation performances in the gas phase. Various aromatic nitration mechanisms (carbon and nitrogen mono–nitration mechanisms) of unprotonated tautomeric PATO species as well as PATO have been designed in gas phase and the reaction states (pre–transition states, transition states, intermediates and nitration products) have been detected belonging to these mechanisms. Nitrations in solution phase have also been analyzed. The reaction states have been detected for carbon and nitrogen mono–nitrations of protonated PATO species in the gas phase. The detonation performances of unnitrated and nitrated PATO products have been presented.Ph.D. - Doctoral Progra

Fluorene based electrochromic conjugated polymers: A review

This review briefly describes electrochromic conductive polymers containing fluorene in the main chain or as a subunit/core. According to the arrangement of the fluorene unit and its chemical location on the chain, polyfluorene family was expressed in three classes; fluorene EC homopolymers, copolymers and functional EC polymers. With its sometimes surprising properties and countless advantages, fluorene monomer has many contributions to the electrochromic conductive polymer chain. Although there are many fluorene derived polymers in the literature that have been functionalized and/or used in various applications, this review only found it appropriate to focus on conductive electrochromic polymers with possessing fluorene chemical units. For this purpose, it has been tried to review and comment on fluorene polymers by comparing their chemical, electrochemical and optical properties in a logical framework. One of the biggest problems of electrochromic conductive polymer researchers is to analyze how the redox and electrochromic properties of polymers, which consist of a functional group, change according to the position on the conjugated polymer chain. For this reason, it is thought that the contribution and guideness of this study to the literature will be considerable

Poly(3,4-ethylenedioxythiophene) electrode grown in the presence of ionic liquid and its symmetrical electrochemical supercapacitor application

WOS:000427373000014Poly(3,4-ethylenedioxythiophene) polymer film (PEDOT-IL) was electrosynthesized in the ionic liquid (IL) 1-ethyl-3-methylimidazolium hydrogen sulphate (EMIMHSO4) medium, which also contains 0.1 M LiClO4 in ACN. For comparison reasons in terms of structure and electrode capacitance performance, PEDOT film was also synthesized electrochemically without IL. The SEM results show that PEDOT-IL film has more porous surface and fine textures with nanometer-diameter than PEDOT polymer. Different electrochemical methods including galvanostatic charge-discharge (CD) experiments, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) were carried out to investigate the applicability of the system as a redox supercapacitor for both polymers. PEDOT-IL electrode shows higher optimum specific capacitance than PEDOT film. Additionally, the symmetrical supercapacitor was assembled from two PEDOT-IL electrodes in LiClO4/ACN medium and exhibited a maximum specific capacitance of 107 F g(-1), an energy density of 11.5 Wh kg(-1) at a power density 13 kW kg(-1), and an excellent cycle life of 96% specific capacitance retention after 1000 cycles.Karamanoglu Mehmetbey UniversityKaramanoglu Mehmetbey University [KMU-BAP-38-M-16]We gratefully acknowledge financial support from Karamanoglu Mehmetbey University (KMU-BAP-38-M-16)

Synthesis and characterization of an electrochromic copolymer based on 9, 10-di (furan-2-yl)anthracene and 3,4-ethylenedioxythiophene

In this study, a new copolymer, which is a combination of two chemical structure (9,10-di(furan-2-yl)anthracene and 3,4-ethylenedioxythiophene was synthesized via electrochemical synthesis methods in the electrolyte medium of 0.1 M TBAPF6/ ACN solution. PEDOT homopolymer was also electrosynthesized for comparator experiments of the polymer formations in the same medium. The characterizations of polymers were achieved with general optical and electrochemical characterization techniques. The corresponding electrochromic copolymer shows blue and lilac color in its neutral and oxidized states, respectively. The copolymer has an optical band gap of 1.65 eV and 24% optical contrast at 500 nm with a high coloration efficiency (170 cm2 /C) and a fast switching time (1.0 s). © 2022 TUBITAK. All rights reserved

Electrosynthesis of a new indole based donor-acceptor-donor type polymer and investigation of its electrochromic properties

WOS:000393253000009The purpose of this research is to synthesize a novel monomer, namely, 1-mety1-2,3-di(thiophen-2-y1)-1H-indole (DTI) and to present optical and electrochemical characterization of its corresponding polymer film, P(DTI). The donor thiophene unit was matched with acceptor indole unit in consideration of donor acceptor-donor approach in order to achieve DTI monomer. This monomer was electropolymerized in the medium 0.1 M LiClO4/Ethanol:ACN solution mixture and a conductive indole based polymer, P(DTI) was obtained. The spectroelectrochemical studies show that P(DTI) has a band gap of 2.45 eV and a color change from pale green to dark green with a switching time of 0.9 s during oxidation and a high coloration efficiency (286 cm(2)/C) at 830 nm. Furthermore, P(DTI) shows good environmental and redox stability with a retention of 85% after 1500th switching. (C) 2016 Elsevier B.V. All rights reserved.Karamanoglu Mehmetbey UniversityKaramanoglu Mehmetbey University [06-M-15]; Yuzuncu Yil UniversityYuzuncu Yil University [FBA-2016-5201]The authors gratefully acknowledge the financial support from Karamanoglu Mehmetbey University (Grant No: 06-M-15) and Yuzuncu Yil University (Project No. FBA-2016-5201)

A comprehensive overview of carbazole-EDOT based electrochromic copolymers: A new candidate for carbazole-EDOT based electrochromic copolymer

In recent years, there has been an increase in the demand for the synthesis of carbazole-EDOT based electrochromic copolymers since this combination of structures facilitates the obtaining of a free standing film on the working electrode and improves the electrochromic properties of the polycarbazole (PC) polymer. In this study, carbazole-EDOT based copolymers with electrochromic properties in the literature were classified into three groups and the effect of changing the carbazole/EDOT order on the polymer chain on the electrochromic properties of the obtained copolymer was tried to be revealed. Moreover, as an example, a new candidate for carbazole-EDOT based electrochromic random copolymer was introduced. Carbazole and EDOT monomers were copolymerized electrochemically in nonacidic medium for a clear and basic comparison. The electrochemical and spectroelectrochemical studies show that the corresponding copolymer, poly(C-co-EDOT), contains freestanding property on working electrode and shows multielectrochromic property. The copolymer gave a λmax value at about 545 nm with a band gap of 1.74 eV. As expected, EDOT monomer inserting to the polycarbazole chain improves electrochemical and optical properties of homopolymer PC. The electrochromic performance of new copolymer was also compared with its homopolymers components (polymer of carbazole (C) and EDOT) and carbazole-EDOT based electrochromic random copolymers in literature. The experiments showed that poly(C-co-EDOT) was an electroactive material with higher coloration efficiency (CE) (258 cm2/C at 900 nm) than that of PC and carbazole-EDOT based random copolymers in literature. DFT theoretical and experimental calculations were also achieved in order to find HOMO and LUMO energy levels besides band gap and compared with each other. No such a theoretical calculation related electrochromic PC polymer and that kind of random electrochromic copolymer has ever been encountered in the studies carried out so far. Since this research is a baseline study for the valuable design of carbazole-EDOT based electrochromic copolymer, it is thought to shed light on the scientists who will work on this subject in the future

Chasing the black electrochromism: A new electrochromic copolymer based on 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[c][1,2,5]thiadiazole and ProDOT

Absorbing all the visible light, in other words, neutral state black electrochromics has a great importance for certain applications such as smart windows, electronic papers, car rear views or displays. In this study, it was focused on a combination of monomers that can absorb entire the visible region. Poly(4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[c][1,2,5]thiadiazole) (PEDAD) is a neutral state green polymer and has a dual absorption band before and after 500 nm, corresponding red and blue regions of the visible spectrum. On the other hand, polymer of dihexyl-3,4-propylenedioxythiphene (PProDOT) has an 400–700 nm optical absorption band with having a maximum at 584 nm. In the light of this information, a new copolymer, consisting of 4,7-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)benzo[c][1,2,5]thiadiazole and ProDOT, was synthesized via electrochemical techniques, to trap the entire visible region. 1:1 eq. of monomer feed was used and a neutral state very-dark copolymer was obtained. The copolymer showed enhanced optical contrast coming from PProDOT, (of having 44% transmittance) and lower band gap coming from PEDAD (of having 1.32 eV). In the oxidized state, the copolymer exhibited transmissive blue, coming from both homopolymers. © 2022 Elsevier Ltd

A new electrochromic copolymer composed of 4,7-di(thiophen-2-yl)benzo[c] [1,2,5] thiadiazole and 3,4-ethylenedioxythiophene

WOS:000876350600014A new electrochromic copolymer based on 4,7-di(thiophen-2-yl)benzo[c] [1,2,5]thiadiazole and 3,4-ethylenedioxythiophene was successfully obtained via the electrochemical polymerization method in the medium of electrolyte solution, which consists of 0.1 M tetrabutylammonium hexafluorophosphate and dichloromethane. In order to compare the electrochemical and chemical properties of the copolymer, the benzothiodiazole derivative and 3,4-ethylenedioxythiophene (EDOT) monomers, which are parts of the copolymer, are electrochemically polymerized, separately in the same environment and concentration with the copolymer. Poly(4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole) (P(TBT)) and poly(3,4-ethylenedioxythiophene) (PEDOT) polymers were obtained. Before starting the electrochemical synthesis, the initial oxidation potentials of the monomers that form the copolymer were compared via the cyclic voltammeter method in this solvent electrolyte medium. Then, electrochemical and spectroelectrochemical characterizations of electrochemically synthesized polymers and copolymers were performed. New copolymer shows metallic blue and centaury blue in its neutral and oxidized states, respectively with a low band gap of 1.32 eV. Moreover, the copolymer has a 59% optical contrast and high coloration efficiency (324 cm2C-1) at 585 nm with a switching time of 2.2 s

A classified and comparative review of Poly (2,5-dithienyl-N-substituted-pyrrole) derivatives for electrochromic applications

WOS:000826870600002WOS:000822992800005PubMed ID:35714424Poly(2,5-dithienyl-1-substituted-pyrrole) derivatives are one of the important classes for conducting polymers, exhibiting versatile electrochromic property besides used material in a broad range of smart applications. This review offers an overview of various SNS derivatives, mostly for electrochromic applications. In this compilation, the designed, synthesized and electrochemically and optically characterized conducting polymers of SNS derivatives in the literature up to today have been classified and comparatively discussed. The polymers of the SNS derivatives collected here have been prepared mostly by electrochemical techniques. According to N-substitutions form pyrrole unit, P(SNS) derivatives were grouped into five sections: N- alkyl-, phenyl-, amine/amide, homo/heterocyclic-, and crosslinked substituted derivatives. Each section mainly includes the structure-property relationship and the comparison of the effect of substitutions on the electrochromic properties of the resulting polymers