10.1021/acsami.6b11321.s001
Yolanda Alesanco
Yolanda
Alesanco
Ana Viñuales
Ana
Viñuales
Germán Cabañero
Germán
Cabañero
Javier Rodriguez
Javier
Rodriguez
Ramón Tena-Zaera
Ramón
Tena-Zaera
Colorless to Neutral Color
Electrochromic Devices Based on Asymmetric Viologens
American Chemical Society
2016
PVA-borax gel polyelectrolytes
i.e
application
easy-to-make neutral-grayish color ECDs
electrochromic devices
electrochromic technology
neutral-grayish colorations
neutral-colored state
device architecture
Neutral Color Electrochromic Devices
viologen
Asymmetric Viologens Electrochromic materials
study reports
2016-10-11 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Colorless_to_Neutral_Color_Electrochromic_Devices_Based_on_Asymmetric_Viologens/4055583
Electrochromic
materials have extensively been investigated because of their potential
fields of application, with a significant growing interest in expanding
the provided colorations. However, among all palette of colors, colorless
electrochromic devices (ECDs) that provide neutral-grayish colorations
with a simple configuration remain a key challenge. The present study
reports on the synthesis of asymmetrically 1-alkyl-1′-aryl-substituted
viologens and their incorporation in PVA-borax gel polyelectrolytes
for ECDs that constitute the simplest device architecture (glass/TCO/EC
gel/TCO/glass). We demonstrate herein that these EC gels based on
single asymmetric viologens provide more neutral-colored state than
their corresponding symmetric viologens (<i>a</i>* and <i>b</i>* ≤ |15|), while maintaining satisfactory colorless
bleached state (%<i>T</i><sub>b</sub> > 70% in the whole
visible range), transmittance changes (i.e., ∼60%) and cyclability
(i.e., ∼15 000 cycles). Additionally, the effect of
the solvent on the observed coloration has also been investigated.
This easy-to-make neutral-grayish color ECDs may significantly extend
the potential of the electrochromic technology, because they adapt
better aesthetically to the surrounding environment, as they are easier
to implement in different applications.