Electrosynthesis of Electrochromic Polymer Membranes Based on 3,6-Di(2-thienyl)carbazole and Thiophene Derivatives

Chung-Wen Kuo; Jui-Cheng Chang; Jeng-Kuei Chang; Sheng-Wei Huang; Pei-Ying Lee; Tzi-Yi Wu

doi:10.3390/membranes11020125

Electrosynthesis of Electrochromic Polymer Membranes Based on 3,6-Di(2-thienyl)carbazole and Thiophene Derivatives

Membranes (Basel). 2021 Feb 9;11(2):125. doi: 10.3390/membranes11020125.

Authors

Chung-Wen Kuo¹, Jui-Cheng Chang^{2

3}, Jeng-Kuei Chang⁴, Sheng-Wei Huang¹, Pei-Ying Lee², Tzi-Yi Wu²

Affiliations

¹ Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 80778, Taiwan.
² Department of Chemical Engineering and Materials Engineering, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan.
³ Bachelor Program in Interdisciplinary Studies, National Yunlin University of Science and Technology, Yunlin 64002, Taiwan.
⁴ Department of Materials Science and Engineering, National Chiao Tung University, No. 1001 University Road, Hsinchu 30010, Taiwan.

Abstract

Five carbazole-containing polymeric membranes (PDTC, P(DTC-co-BTP), P(DTC-co-BTP2), P(DTC-co-TF), and P(DTC-co-TF2)) were electrodeposited on transparent conductive electrodes. P(DTC-co-BTP2) shows a high ΔT (68.4%) at 855 nm. The multichromic properties of P(DTC-co-TF2) membrane range between dark yellow, yellowish-green, gunmetal gray, and dark gray in various reduced and oxidized states. Polymer-based organic electrochromic devices are assembled using 2,2'-bithiophene- and 2-(2-thienyl)furan-based copolymers as anodic membranes, and poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonic acid) (PEDOT-PSS) as the cathodic membrane. P(DTC-co-TF)/PEDOT-PSS electrochromic device (ECD) displays a high transmittance change (ΔT%) (43.4%) at 627 nm as well as a rapid switching time (less than 0.6 s) from a colored to a bleached state. Moreover, P(DTC-co-TF2)/PEDOT-PSS ECD shows satisfactory optical memory (the transmittance change is less than 2.9% in the colored state) and high coloration efficiency (512.6 cm² C^-1) at 627 nm.

Keywords: cycling stability; dual-type electrochromic device; electrochromic behavior; spectroelectrochemical property; transmittance.