Polycarbazole Electropolymerization Materials with Excellent Electrochromic Performance Based on Phenothiazine/Phenoxazine Group. Issue 18 (3rd August 2022)

• Record Type: Journal Article
• Authors: Huang, Qidi; Chen, Jianai; Shao, Xiongchao; Dong, Yujie; Li, Weijun; Zhang, Cheng
• Is Part Of: Macromolecular chemistry and physics. Volume 223:Issue 18(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-03
• Subjects: carbazole -- electrochemical polymerization -- electrochromic -- organic small molecules -- well‐defined structures; Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.202200059
• Languages: English
• ISSNs: 1022-1352

Abstract

Abstract: Electrochromic small molecules suffer from the difficult film processibility and serious dissolvability at their oxidation state, which greatly limit their applications in electrochromic areas. Here, well‐defined electrochemical polymer structures, pCZ‐FSQ and pCZ‐FEQ, are obtained by taking advantage of the unique electrochemical dimerization of carbazole, and low redox‐potential phenothiazine and phenoxazine groups are introduced as an electrochromic color‐changing unit with the interruption of conjugation between them via an alkyl chain linkage. The obtained polymer films pCZ‐FSQ and pCZ‐FEQ are composed of the independent dimeric carbazole and organic small molecule units. Finally, they exhibit outstanding electrochromic properties with optical contrast of more than 50%, switching time of less than 1 s, excellent stability (over 500 cycles of optical stability), and ultrahigh coloration efficiency (276 cm 2 C −1 for pCZ‐FSQ, 384 cm 2 C −1 for pCZ‐FEQ). This is thought to be greatly attributed to the well‐defined electrochemical polymer structures with dual electrochromic color‐changing properties of both phenothiazine/phenoxazine and dimeric carbazole. This can also provide some implications for the future in‐depth study of small molecule electrochromism and the solution to the problem of difficult processing of small molecules. Abstract : Taking advantage of the fact that carbazole electropolymerization can only form dimers, organic polymer films pCZ‐FSQ and pCZ‐FEQ with well‐defined structures, which exhibit excellent electrochromic properties due to structural controllability, are obtained; meanwhile, the problem of poor processability of electrochromic organic small molecules is also solved well.