Abstract
Synthesis of 3-(4-fluorophenyl)thieno[3,2-b]thiophene (FPhTT) and 3,3’-(4- fluorophenyl)dithieno[3,2-b;2’,3’-d]thiophene (FPhDTT) were achieved starting from 3-bromothiophene and 3,4-dibromothiophene, respectively. They were electropolymerized and the resulting polymers P[FPhTT] and P[FPhDTT] were characterized by diverse electrochemical methods such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), galvanostatic charge-discharge (GCD), electrochemical quartz crystal microbalance (EQCM) and spectroelectrochemical measurements. Mechanism of electropolymerization of the monomers was supported by DFT level calculations. Band gaps of P[FPhTT] and P[FPhDTT] were calculated as 1.63 and 1.77 eV, respectively, from the onset absorptions of the absorption spectra. From EIS measurements, the highest capacitance values of P[FPhTT] and P[FPhDTT] were calculated to be 39.4 and 281.7 Fg1−, respectively, when the applied potentials were equal to their oxidation peak potentials. Surface characterization of the P[FPhTT] and P[FPhDTT] films on ITO electrodes were performed by atomic force microscope (AFM) and the results suggested that P[FPhDTT] had more porous surface. GCD results indicated that P[FPhDTT] had higher energy density than P[FPhTT], possibly due to its porous structure. According to the ECD results, P[FPhTT] has more stable optical properties. As a conclusion, P[FPhDTT] might be suggested for energy storage applications while P[FPhTT] could be suitable for electrochromic devices.
Original language | English |
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Article number | 138837 |
Journal | Electrochimica Acta |
Volume | 390 |
DOIs | |
Publication status | Published - 10 Sept 2021 |
Bibliographical note
Publisher Copyright:© 2021
Funding
In this work, TT and DTT structures possessing Ph group having strong electron-withdrawing F atom, FPhTT and FPhDTT , were synthesized, polymerized and characterized by electrochemical and spectrophotometric measurements. Electrochemical polymerization and molecular orbitals of the monomers were supported by DFT calculations using Gaussian 09 program. Morphological properties of P[FPhTT] and P[FPhDTT] films on ITO electrodes were characterized by AFM. We thank The Scientific and Technological Research Council of Turkey (TUBITAK) for grants to Sebahat Topal and Sema Topal (TUBITAK BIDEB 2211A), and also thank The Higher Education Council of Turkey (YOK) (Ph.D. 100/2000 YOK) for for grants to Sebahat Topal. In addition, we would like to thank Istanbul Technical University Scientific Research Projects (Project No: 42325) and Unsped Global Logistics for their financial support. We are indebted to National Center for High Performance Computing (UHeM) under grant number <4007702020> (Sebahat Topal project: editmb) for the computational chemistry studies.
Funders | Funder number |
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Higher Education Council of Turkey | 100/2000 YOK |
National Center for High Performance Computing | |
TUBITAK | BIDEB 2211A |
YOK | |
Ulusal Yüksek Başarımlı Hesaplama Merkezi, Istanbul Teknik Üniversitesi | |
Türkiye Bilimsel ve Teknolojik Araştirma Kurumu | |
Istanbul Teknik Üniversitesi | 42325 |
Keywords
- 3,3’-(4-Fluorophenyl)dithieno[3,2-b;2’,3’-d]thiophene
- 3-(4-Fluorophenyl)thieno[3,2-b]thiophene
- Capacitive and electrochromic behavior
- DFT
- EQCM
- Electropolymerization