Electrochromic copolymers of 2,5-dithienyl-N-substituted-pyrrole (SNS) derivatives with EDOT: Properties and electrochromic device applications

2,5-dithienyl-N-substituted-pyrrole (SNS) derivatives are one of the most preferred conjugated systems for obtaining conducting polymers since they have low oxidation potential and ease of electrochemical polymerization. SNS backbone can be substituted from the nitrogen atom on the pyrrole unit and resulting SNS derivatives allow fine tuning on the spectroelectrochemical properties. Moreover, copolymerization of SNS derivatives leads to further tuning or enhancement on the features of the obtained copolymer. 3,4-Ethylenedioxythiophene (EDOT) is the most promising conjugated unit used in copolymerization of conjugated systems. In this review, electrochemically synthesized conducting copolymers of SNS derivatives with EDOT in the literature were collected and discussed. According to N-substitutions, SNS derivatives in copolymers were grouped into four sections: phenyl-, amine-, alkyl-, and crosslinked- substituted derivatives. In each section, the effect of different substitutions and amount of EDOT incorporation on the electrochromic properties of the resulting copolymers were both evaluated in the text and summarized in the tables. Electrochromic device applications, if exist, of related copolymers were also discussed. Here, an overview is presented of available electrochromic copolymers for SNS derivatives with EDOT, providing a perspective for scientists aiming to design new SNS derivatives for copolymerization.