Both p and n-Dopable, Multichromic, Napthalineimide Clicked Poly(2,5-dithienylpyrrole) Derivatives

Abstract

Herein we disclose construction and characterization of both p- and n-dopable, multichromic 2,5-dithienylpyrrole (SNS) based electrochromic films and demonstrate usefulness of click chemistry on functionalization of SNS derivatives to enhance optoelectronic properties of the resultant polymer. For this purpose, 1,8-naphthalimide containing monomer (SNS-Napth) was synthesized through click chemistry for the first time. SNS-Napth was subjected to electrochemical polymerization and electrochromic properties of the resultant polymer was investigated in detail. Additionally, 16 different copolymers were synthesized by controlling electrochemical copolymerization conditions such as feed ratio, electrochemical polymerization method and potential. All the polymers revealed ambipolar redox behavior where reversible n- and p-type doping was achieved in cathodic and anodic regime, respectively. The homopolymer had a bandgap of 3.15 eV and displayed yellow-blue color variation upon doping. Copolymers, on the other hand, displayed multichromic behavior where a direct correlation between polymerization conditions (feed ratio, polymerization potential) and spectral behavior, color was determined. Among all copolymers, the ones which were synthesized in excess EDOT medium displayed higher reversibility and shorter switching times whereas amplification of polymerization potential seems to be ineffective in terms of switching times.

Multichromic polymers based on pyrene clicked thienylpyrrole

“…Compared with its pioneers such as PSNS‐N 3 ( E g = 2.50 eV), PSNS‐Fc ( E g = 2.61 eV) and PSNS‐naphth ( E g = 3.15 eV), P(SNS‐pyrene) revealed a higher bandgap, which emphasizes the impact of the size of the anchored group on the bandgaps of PSNS derivatives. During oxidation P(SNS‐pyrene) displayed a color transition from light green to blue whereas PSNS‐N 3 , PSNS‐Fc and PSNS‐naphth revealed yellow to blue coloration. In order to quantify and describe physically the human color perception, colorimetry studies on P(SNS‐pyrene) were performed and the relevant data are provided in Table .…”

“…The presence of vibronic features in the absorption spectrum is considered to be related to the high degree of order which was reinforced by the planar group, pyrene. Among many PSNS derivatives, including PSNS‐naphth and PSNS‐pyrene, the only polymer that possessed vibronic features was P(SNS‐pyrene). This might be related not only to the presence of the planar group but also to the presence of flexible alkyl chains that allow for suitable orientation and enhance the degree of order of the polymer.…”

“…The reaction has significantly low yield in the case of bulky and/or acceptor groups. To overcome this problem we have recently synthesized a clickable SNS derivative which provides a major opportunity for diversification of the SNS structure with interesting functional groups such as ferrocene and 1,8‐naphthalimide . In fact, all these studies have revealed the effectiveness of the approach and resulted in novel PSNS derivatives with enhanced optoelectronic properties, including reversible n‐type doping.…”

A Low Band Gap Benzimidazole Derivative and Its Copolymer with 3,4-Ethylenedioxythiophene for Electrochemical Studies

“…In literature, this strategy was applied for different CPs to improve the mentioned properties. [3][4][5][6][7][8] Due to outstanding electrochemical properties such as; low oxidation potential, good stability and low bandgap, EDOT is one of the excellent candidates for electrochemical copolymerization. 23 As a result, in this study copolymerization technique was applied to improve the electrochemical properties of this novel monomer (BIMN) by insertion of EDOT unit.…”

“…[3][4][5] Over the last two decades conducting polymers (CPs) have received considerable attention due to their electrochemical and optical properties, [6][7][8] low cost, tunable band gaps [3][4][5] and fast switching times. 9 Modification of bandgap of conducting polymer is a crucial strategy to achieve desirable electrochromic properties.…”