Using room temperature ionic liquid to fabricate PEDOT/TiO2 nanocomposite electrode-based electrochromic devices with enhanced long-term stability

In this work, poly(3,4-ethylenedioxythiophene)(PEDOT) was electrochemically incorporated with nano- and mesoporous TiO2 films to form PEDOT/TiO2 nanocomposite electrochromic electrodes. TiO2 films were introduced to enhance the interfacial adhesion of the polymers to the substrates and thus increase the long-term stability of electrodes of electrochromic devices (ECDs). Room temperature ionic liquid (RTIL)- 1-butyl-3-methyl-imidazolium tetrafluoroborate ([BMIM]BF4) was employed to serve as electrolyte during the entire fabrication processes. With these efforts, the ECDs were found to retain up to 95% of their optical response and electroactivity after 10,000 deep, and double potential steps, exhibiting enhanced long-term stability.