Effect of Dithienopyrrole Unit on Electrochromic and Optical Properties of Benzotriazole‐Based Conjugated Polymers

Abstract

A series of benzotriazole (BTz)‐ and dithienopyrrole (DTP)‐based three polymers; poly[2‐(2‐dodecyl‐2H‐benzo[d][1,2,3]triazol‐4‐yl)‐4‐hexyl‐4H‐dithieno[3,2‐b:2′,3′‐d]pyrrole] (P1), poly[2‐ (5‐(2‐dodecyl‐7‐(thiophen‐2‐yl)‐2H‐benzo[d][1,2,3]triazol‐4‐yl)thiophen‐2‐yl)‐4‐hexyl‐4H‐dithieno[3,2‐b:2′,3′‐d]pyrrole] (P2), and poly[2‐(5‐(2‐dodecyl‐7‐(4‐hexylthiophen‐2‐yl)‐2H‐benzo[d][1,2,3]triazol‐4‐yl)‐3‐hexylthiophen‐2‐yl)‐4‐hexyl‐4H‐dithieno[3,2‐b:2′,3′‐d]pyrrole] (P3) was synthesized via Stille coupling. To investigate the effect of the π‐bridges on the electrochromic properties of BTz‐based polymers, thiophene and 3‐ hexylthiophene was incorporated between BTz and DTP moiety. Different π‐bridges affected the HOMO and LUMO energy levels, coloration efficiency, switching time, and optical contrast.

Synthesis and electrochromic properties of triphenylamine containing copolymers: Effect of π-bridge on electrochemical properties

“…Our group have designed and synthesized a series of D–A‐type polymers with BTz as the acceptor unit together with fullerene, benzene, thiophene, dithienopyrrole, and stilbene as the donor units for investigating electrochemical and spectroelectrochemical features. In an attempt to extend the family of the TPA‐comprising conducting polymers, here we designed, synthesized, and compared three new TPA‐ and BTz‐containing D–π–A‐type polymers ( P1 , P2 , P3 ) with conjugated bridges (thiophene and benzene) between the TPA donor and BTz acceptor entities.…”

D-A-D Compounds Combining Dithienopyrrole Donors and Acceptors of Increasing Electron-Withdrawing Capability: Synthesis, Spectroscopy, Electropolymerization, and Electrochromism

“…Moreover, the color of the studied polymers can be significantly modulated by the acceptor unit selection, as demonstrated not only in this research but also in previous reports. 74,75 Thus, the studied polymers are promising visible and NIR electrochromes. Below, detailed descriptions of the electrochromic properties of the polymers tested are presented.…”

Fabricating multicolored electrochromic devices using conducting copolymers

“…In common with several other research groups, this route is convenient for the preparation of 'trimeric' thiophene-pyrrole-thiophene derivatives substituted at the N atom of the pyrrole ring [15][16][17][18]. This strategy yields centrosymmetric polymer precursors and seeks to minimize the steric influence of the central substituent through the addition of the thiophene spacers.…”