A portable electrochromic display window (7 cm x 5 cm) has been constr
ucted using a polyaniline-coated SnO2 glass plate and an AlCl3(aq) mel
t. The window colour can be switched from dark green to yellow or colo
urless by applying a small voltage of -0.5 to 2.5 V. It exhibits a fas
t response time (ms) and a long cycle life (1000).