Effect of the donor units on the properties of fluorinated acceptor based systems


Creative Commons License

Çakal D., Akdağ A., Cihaner A., Önal A. M.

Dyes and Pigments, vol.185, 2021 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 185
  • Publication Date: 2021
  • Doi Number: 10.1016/j.dyepig.2020.108955
  • Journal Name: Dyes and Pigments
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: Electropolymerization, Electrochromism, Dihedral angle, Benzothiadiazole, Furan, Thiophene, Selenophene, LOW-BANDGAP POLYMERS, ELECTROCHROMIC POLYMER, CONJUGATED POLYMERS, BENZOTHIADIAZOLE, PERFORMANCE, THIOPHENE, COPOLYMERS, MOLECULES, CONTRAST

Abstract

© 2020 Elsevier LtdA new series of monomers in the donor-acceptor-donor array, namely 5-fluoro-4,7-di(furan-2-yl)benzo[c][1,2,5]thiadiazole (F2BT-F), and 5-fluoro-4,7-di(selenophen-2-yl)benzo[c][1,2,5] thiadiazole (S2BT-F), bearing 5-fluorobenzo[c][1,2,5]-thiadiazole as the acceptor moiety and furan and selenophene as the electron donating groups was synthesized and polymerized electrochemically. To compare heteroatom effect, thiophene analogue of newly synthesized F2BT-F and S2BT-F namely, (5-fluoro-4,7-di(thiophen-2-yl)benzo[c][1,2,5] thiadiazole (T2BT-F)) and its corresponding polymer were also synthesized. Effect of donor units on the electrochemical and optical properties of fluorinated acceptor based systems was investigated in terms of the effect of different sized heteroatoms in five-membered rings on the dihedral angle and planarity. Theoretical calculations also suggested a deviation from planarity upon fluorination. Moreover, electrochemically obtained polymers possess low bandgap values (1.62 eV–1.68 eV for PF2BT-F and PS2BT-F, respectively) and exhibited electrochromic properties with relatively low switching times.