Enhanced Electrochromic Properties by Using a CeO₂ Modified TiO₂ Nanotube Array Transparent Counter Electrode

A new kind of electrochromic device composed of a CeO2 modified TiO2 nanotube array counter electrode and a working electrode of P3MeT film was reported. The counter electrode was fabricated by electrodepositing CeO2 nanoparticles onto the walls of anodized TiO2 nanotubes. The CeO2 modified TiO2 nanotube array counter electrode keeps a high transparency under working voltage. The charge capacity of CeO2 modified TiO2 nanotube array has an increase of 30% than that of un-modified TiO2 nanotube array electrode. Compared with the electrochromic device with a TiO2 nanotube array film electrode, the CeO2 modified TiO2 nanotube counter electrode based EC device has a fast decoloration time of 0.8 s. The fast response attributes to the high effective surface area and the fast charge transportation along the nanotube walls.