Abstract: A new coupling electrochromic solution was investigated by introducing titanium ion into viologen solution. The solution-based electrochromic device was assembled by using this coupling solution. The transmittance of this electrochromic device decreased from 80% to 20% in the wavelength of 600nm, which was characterized by UV-Vis spectra. The bleaching time of this electrochromic device was less than 2s and this electrochromic device had a character of self-erasing process.

Key words: electrochromic devices, coupling solution system, viologen, bleaching time