Copolymers derived from 3-hexylthiophene and 3-methoxythiophene as potential active layers for polymeric electrochromic devices

Abstract

Three copolymers based on 3-substituted polythiophenes were synthesized. All copolymers, poly(3-hexylthiophene-co-3-methoxythiophene) P(3HT-co-3MOT), with different ratios between the 3HT and 3MOT units (2:1, 2:1, and 1:2), were characterized by FT-IR, UV-Vis, thermal analysis (TG), cyclic voltammetry, and chronoabsorptometry. The characterizations confirmed the successful formation of the materials, as well as a reversible color change from orange to blue (electrochromism). The optical and spectroelectrochemical studies showed that adjusting the ratio between the monomer units in the polymer chain can be a viable strategy for fine-tuning both the maximum absorption wavelength of the materials and their electrochromic response time.