
WO3 powder can be used to prepare an electrochromic device in form of a tungsten trioxide electrochromic film. The reason why the obtained device has the electrochromic effect is that the tungsten trioxide nano film has the surface effect. More details, please visit: http://www.tungsten-powder.com/tungsten-oxide.html It is reported that the electrochromic effect was first observed on alkali-halogen crystals. Light absorption was observed when a voltage was applied to the two electrodes fabricated on the alkali halide crystal and heated to about…