Utilization of novel bithiazole based conducting polymers in electrochromic applications

• Published in: Smart materials and structures 2012-02, Vol.21 (2), p.25019-1-8
• Main Authors: Camurlu, Pinar, Gültekin, Cemil
• Format: Article
• Language: English
• Subjects: Applied sciences; Conducting polymers; Copolymers; Devices; Electrical, magnetic and optical properties; Electrochromism; Energy gaps (solid state); Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Properties and characterization; Switching; Synthesis; Utilization
• ISSN: 0964-1726; 1361-665X
• DOI: 10.1088/0964-1726/21/2/025019

In this paper we disclose the synthesis of a novel monomer (2,2′-di-pyrrol-1-yl-[4,4′]bithiazolyl, PyDBTH) and the optoelectronic properties of the resultant conducting polymers. PyDBTH was synthesized via the Clauson-Kaas reaction of 2,2′-diamino-4,4′-bithiazole with 2,5-dimethoxytetrahydrofuran in acetic acid which was characterized by 1H, 13C-NMR, FTIR and MS analyses. Homopolymerization and copolymerization (in the presence of 3,4-ethylenedioxythiophene) were achieved in a tetrabutylammonium hexafluorophosphate (TBAPF6) dichloromethane system. The electrochemical and electrochromic properties of the homopolymer and copolymers were examined by cyclic voltammetry, FTIR, spectroelectrochemistry and kinetic studies. Depending on the synthesis conditions, the bithiazole based polymers exhibited optical band gaps ranging from 2.60 to 1.75 eV and the copolymers displayed multichromism within a wide span of the visible spectrum. The copolymers revealed short switching times and useful optical contrast of 0.6 s and 54%, respectively. Due to its favorable electrochromic properties, utilization of bithiazole based polymers in electrochromic devices was also investigated. These devices exhibited low switching voltages and switching times with reasonable stability under atmospheric conditions.