Electrochromism is the phenomenon displayed by some color changing materials when a burst of charge is applied.
Viologens (Vio) are cathodic electrochromic materials, and triphenylamines (TPA) are anodic electrochromic materials.
Here, we reported a new electrochromic compound composed of Vio, TPA and phosphonic acid groups, thus the
molecules can be anchored on electrode, which will lead to faster switching speed and high stability. An electrochromic
device was assembled using the new Vio as primary electrochromes and Prussian blue as secondary electrochromes. The
device exhibits high transparency. In addition, it shows fast switching speed and good stability.