Browsing by Author "Carbas, Buket Bezgin"

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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]thia-diazole and ProDOT
(2022) Ergun, Emine Gill Cansu; Carbas, Buket Bezgin
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 elec-trochemical 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.
A classified and comparative review of Poly (2,5-dithienyl-N-substituted-pyrrole) derivatives for electrochromic applications
(2022) Carbas, Buket Bezgin; Ergun, Emine Gul Cansu
Poly(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.
Electrochromic copolymers of 2,5-dithienyl-N-substituted-pyrrole (SNS) derivatives with EDOT: Properties and electrochromic device applications
(2022) Ergun, Emine Gul Cansu; Carbas, Buket Bezgin
2,5-dithienyl-N-substituted-pyrrole (SNS) derivatives are one of the most preferred conjugated systems for obtaining conducting polymers since they have low oxidation potential and ease of electrochemical polymerization. SNS backbone can be substituted from the nitrogen atom on the pyrrole unit and resulting SNS derivatives allow fine tuning on the spectroelectrochemical properties. Moreover, copolymerization of SNS derivatives leads to further tuning or enhancement on the features of the obtained copolymer. 3,4-Ethylenedioxythiophene (EDOT) is the most promising conjugated unit used in copolymerization of conjugated systems. In this review, electrochemically synthesized conducting copolymers of SNS derivatives with EDOT in the literature were collected and discussed. According to N-substitutions, SNS derivatives in copolymers were grouped into four sections: phenyl-, amine-, alkyl-, and crosslinked- substituted derivatives. In each section, the effect of different substitutions and amount of EDOT incorporation on the electrochromic properties of the resulting copolymers were both evaluated in the text and summarized in the tables. Electrochromic device applications, if exist, of related copolymers were also discussed. Here, an overview is presented of available electrochromic copolymers for SNS derivatives with EDOT, providing a perspective for scientists aiming to design new SNS derivatives for copolymerization.
Toward Camouflage Colors by Electrochemical Copolymerization
(2023) Ergun, Emine Gul Cansu; Carbas, Buket Bezgin
In this paper, a new electrochromic copolymer containing 6,9-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-1,2,3,4-tetrahydrophenazine (EBE) and 4-(9-benzyl-9H-carbazol-3-yl)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazole (CBT) in the main chain was reported. The homopolymers, (Poly(EBE) and Poly(CBT)), were also prepared via electrochemical polymerization and their electrochemical, spectroelectrochemical and electrochromic properties were analyzed in order to compare their properties with those of copolymer (Poly(EBE-co-CBT)). The copolymer exhibited good switching property for military camouflage necessities with color change from hues of brown to green. Furthermore, it has been tried to analyze the effects of combination of two donor-acceptor-donor (DAD) type monomers with different symmetries on the copolymer properties. A viable strategy for electrochromic adaptive camouflage was presented. New electrochromic copolymer film containing 6,9-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-1,2,3,4-tetrahydrophenazine and 4-(9-benzyl-9H-carbazol-3-yl)-7-(thiophen-2-yl)benzo[c][1,2,5]thiadiazole in the main chain was synthesized using electrochemical polymerization technique. The resulting copolymer film matched the military camouflage necessities with having color changes from hues of brown to green. Moreover, an "asymmetric and symmetric donor-acceptor-donor type monomeric combination" in an electrodeposited copolymer film was first time presented.image