Influence of side chains on electrochromic properties of green donor-acceptor-donor polymers
Artikel i vetenskaplig tidskrift, 2011

Three solution processable cathodically coloring green electrochromic polymers, based on 2,3-diphenyl-5,7-di(thiophen-2-yl)thieno[3,4-b]pyrazine, have been synthesized by oxidative FeCl3 polymerization. The polymers were designed with solubilizing alkyl and oligoethylene oxide side chains to achieve solubility and processability. All three polymers have a small electrochemical bandgap (1.8-1.9 eV) and low oxidation potentials. Spectroelectrochemical studies of polymer films on ITO reveal that the alkyl side chains in head-to-head position on the polymer backbone promote a defined high-energy absorption peak and suppress tailing of charge-carrier absorption into the visible region. Kinetic studies, based on transmission measurements applying a square-wave potential between reduced and oxidized states, show that the polymer with exclusively oligoethylene oxide side chains (P3) had the fastest response times, monitored at the low-energy absorption maxima. The best performing polymer (P1) showed a good optical contrast in the visible region with a Delta T of 26% at 700 nm. An initial test of the electrochemical stability showed that the oligoethylene oxide containing polymers had superior stability over 500 full switches.

distributions

design

realization

oxidized state

solar-cells

Electrochromism

Conjugated polymer

maldi-ms

copolymers

Spectroelectrochemistry

neutral state

MALDI-TOF

FeCl3-polymerization

polymerization

processable green

Författare

Stefan Hellström

Chalmers, Kemi- och bioteknik, Polymerteknologi

Tianqi Cai

Chalmers

East China University of Science and Technology

Olle Inganäs

Linköpings universitet

Mats Andersson

Chalmers, Kemi- och bioteknik, Polymerteknologi

Electrochimica Acta

0013-4686 (ISSN)

Vol. 56 10 3454-3459

Ämneskategorier

Kemi

DOI

10.1016/j.electacta.2010.11.018

Mer information

Senast uppdaterat

2018-09-10