Poly(3,4-dioxythiophene) soft nano-network with a compatible ion transporting channel for improved electrochromic performance

Abstract

Different compared to optoelectronics based on electron transformation, ion transport plays important roles in electrochromic applications. To improve ion transport properties, a novel poly(3,4-dioxythiophene) dimer (PM-BTE) was electropolymerized by an alkoxyl connected 3,4-dioxythiophene dimer and fully characterized. The PM-BTE soft nano-networks exhibit excellent electrochromic properties, which show reversible oxidization and reduction accompanied from dark blue to brown yellow, have an optical contrast ΔT = 38.8%, coloration efficiencies of 263.5 cm² C⁻¹ at 900 nm, low switching voltages and a response of time 1.8 s, with excellent stability and colour persistence. The electrochromic performance is well promoted compared with that of PEDOT (one-fold in coloration efficiency and 60% in response time for the best), which was found to be a result of the as formed PM-BTE films showing a soft nano-network and providing a compatible ion transport channel.