Characteristics of dual‐type electrochromic devices based on poly(ethylene oxide) copolymers

Abstract

Dual‐type polymer electrochromic devices based on [(3‐thienyl)methylmethacrylate]‐co‐[p‐vinyl benzyloxy poly(ethylene oxide)]/polythiophene and thiophene‐capped poly(ethylene oxide)/polythiophene and ethylene dioxythiophene were constructed via electropolymerization. Spectroelectrochemistry, switching ability and stability of the devices were investigated using UV‐visible spectrophotometry and cyclic voltammetry. These devices exhibit low switching voltages and short switching times with reasonable switching stability under atmospheric conditions. Copyright © 2006 Society of Chemical Industry

Matched‐dual‐polymer electrochromic lenses, using new cathodically coloring conducting polymers, with exceptional performance and incorporated into automated sunglasses

“…[92][93][94] Electrochemical and Electrochromic Properties of the Dual-Polymer Lenses and Comparison of Well-Matched and Poorly Matched CP Pairs As briefly noted above, nearly all complimentarily coloring (dual-polymer) CP electrochromics reported thus far in the literature. [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71] have used CPs that are relatively poorly matched electrochemically and electrochromically. One, exemplary manifestation of poor matching is that, in a 2-electrode device, at an applied potential at which one CP is in its fully oxidized form, its complimentary CP is not in its fully reduced form.…”

“…To the best of published knowledge, [75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90][91][92][93][94] this is the best observed thus far in a dual-polymer electrochromic device based on CPs. (Again, it is emphasized, further that our data are "real-life," taken with air in the reference compartment of the spectrometer, in contrast to nearly all of the data reported in the literature, [24][25][26][27][28][29][30][31][32][33][34][35][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69]…”

“…To the best of our knowledge and based on an extensive search of the literature, the electrochromic lenses and sunglasses we report herein represent the best visible‐region electrochromic performance for dual‐polymer CP electrochromic systems to date. They also are, to our knowledge, the first practical implementation in working sunglasses, that is, they represent practical, functional, and applied polymers.…”

“…[44][45][46][47][48][49][50][51][52] A subset of CP electrochromic systems, those based on "complimentarily coloring" or "dual-polymer" CPs, have seen more recent development and have been extensively described. [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71] In these systems, a "cathodically coloring" CP on one electrode is paired with an "anodically coloring" CP on the other, so that they reinforce each other in lightening and darkening. Some improvements in cyclability [i.e., number of light/ dark (L/D) cycles before degradation] and switching time is also observed in these systems.…”

“…Complimentarily coloring, dual-polymer electrochromic devices ("lenses") made with these new monomers constituting the cathodically coloring polymer (used singly as well as in the form of copolymers), paired with several anodically coloring poly(aromatic amines), which we had reported on earlier, 23,44,45,48 again used singly as well as in the form of copolymers. The cathodically and anodically coloring polymer pairs in these devices are shown to be nearly "perfectly" matched electrochemically and electrochromically, in contrast to nearly all prior art [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71] where the cathodically and anodically coloring polymers are poorly matched. The resulting electrochromic lenses display very high L/D contrast (typically up to 70/7% or 50/0.5% Transmission, integrated over the visible spectrum ("real-life," against air reference, not substrate reference, see below), very high cyclability (>10 K cycles) and very long (multiple-years) shelf life.…”