Color control in π-conjugated organic polymers for use in electrochromic devices

The π-conjugated organic polymers combining mechanical flexibility, and ease in band-gap/color-tuning via structural control, along with the potential for low-cost scalability and processing, are attractive in the fast-growing area of plastic electronics. Combining high contrast ratios, fast response times, and narrow potential windows of application with the perspective for long-term optical stability, processable electrochromic polymers (ECPs) are now impacting the development of both transmissive and reflective EC technologies. The next generation of electrochromic polymers should intend to address a number of essential aspects including the compromise between solution-processability and film-to-substrate adhesion upon repeated switching. Correct use and implementation of the existing characterization toolbox for polymer electrochromism will be a key variable in the overall equation leading to widespread applications of this fascinating technology.