An ultrafast electrochromic display is fabricated based upon well defined nanotube arrays of poly (3,4-ethylenedioxythiophene), PEDOT (see Figure). The thin nature of the nanotube walls (10-20 nm) offers a short ion-diffusion distance, which results in an ultrafast switching rate (color-switching time < 10 ms). The arrayed long nanotube structure furnishes strong coloration.