A fast switching, low band gap, p- and n-dopable, donor-acceptor type polymer

Gunbas G. E., ÇAMURLU P., Akhmedov I. M., TANYELİ C., ÖNAL A. M., Toppare L.

JOURNAL OF ELECTROANALYTICAL CHEMISTRY, vol.615, no.1, pp.75-83, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 615 Issue: 1
  • Publication Date: 2008
  • Doi Number: 10.1016/j.jelechem.2007.11.035
  • Journal Name: JOURNAL OF ELECTROANALYTICAL CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.75-83
  • Keywords: donor-acceptor polymers, electrochromism, n- and p-dopable polymers, NIR, electrochemical polymerization, ELECTROCHROMIC PROPERTIES, CONDUCTING COPOLYMERS, CONJUGATED POLYMERS, THIOPHENE, DERIVATIVES, FILMS, DIODES, REDOX, UNITS
  • Middle East Technical University Affiliated: Yes

Abstract

A new electrochromic polymer, poly(2,3-diplienyl-5,7-bis(3,4-ethylenedioxy-2-thienyl)thieno[3,4-b]pyrazine) (PGS) is electrochemically synthesized and its electrochromic properties are reported. PGS showed well defined electrochemical characteristics with a relatively low oxidation potential of 0. 18 V vs Ag/Ag+. Polymer also exhibited a definite redox couple at applied cathodic potentials, indicating n-doping characteristic of the polymer. Spectroelectrochemistry and previously unattempted technique, ESR data was utilized to confirm the existence of dual type pi-pi* transitions centered at 522 nm and 1062 nm. The polymer exhibits multi-color electrochromism where three distinct colors are achievable by varying the redox state of the polymer between saturated red-purple color, blue and colorless-gray in neutral, n- and p-doped states, respectively. Copolymerization as a facile method to tune the electrochromic properties of the material was also realized in the presence of 2,2'-bis(3,4-ethylenedioxythiophene) (BiEDOT). Both polymers exhibit very short switching time (0.4 s) and express more than 45% change in the transmittance in the near-IR region, which could make these polymers useful in applications in NIR electrochromic devices. (c) 2007 Elsevier B.V. All rights reserved.