D‐A type hybrid polymers based on EDOT and various benzodiazoles for electrochromic materials

Abstract

Two donor units (D)‐acceptor units (A) type monomers were synthesized by Stille coupling reaction, and then three D‐A type hybrid polymers based on 3,4‐ethylenedioxythiophene and various benzodiazoles were synthesized by electrochemical polymerization. Spectroelectrochemical and kinetic studies of these polymers showed that all polymer films exhibited excellent electrochromic behavior, obvious optical contrast, and excellent stability. Among them, the response time of P3 film was the shortest (tc = 1.6 s, tb = 2.2 s), the coloring efficiency of P2 film was the highest (CE = 333 cm2·C−1), and the stability of P1 was the best (the ΔT loss of P1 after 1000 s cycles is only 2.3%). Therefore, these data prove that these new polymers have great potential in applications as electrochromic materials.

Electrochromic Insight on Electro‐Deposited Copolymers of Push‐Pull Conjugated Systems with 3,4‐Ethylenedioxythiophene (EDOT) and Other Conjugated Units

“…During the literature survey, we recognized a lack of theoretical works especially in electro-deposited copolymer studies (In the scope of this review, only 2 copolymers supported their experimental results by theoretical work. [58,59] While this is the case, a brief discussion about basic theoretical aspects of push-pull CP design may serve as a guide for the readers. In the light of theoretical studies, planarization of the polymer chain is important to decrease the band gap.…”

“…copolymers via electrochemical techniques. [59] The electrochemical and electrochromic properties were significantly improved via copolymerization with EDOT unit. The copolymer films showed promising electrochromic and optical properties with great stability.…”

“…Hou et al. synthesized two push‐pull type conjugated monomers (benzothiadiazole‐hexylthiophene ( 18‐a ) and benzoselenodiazole‐hexylthiophene ( 18‐b ) via Stille coupling reaction, and then prepared benzodiazoles and EDOT comprising copolymers via electrochemical techniques [59] . The electrochemical and electrochromic properties were significantly improved via copolymerization with EDOT unit.…”