From the mid-1970s to the early 1980s, most studies on the electrochromic properties of tungsten trioxide have focused on electronic display devices. However, due to the limitation of their lower color conversion rate, since then, research has been turning to new fields such as smart windows. Although the latter is less demanding for color response time than display devices, until now, this is still the focus of widespread concern.

In order to meet the current needs of people in different seasons and different periods of indoor lighting on the amount of light, the smart window that can dynamically adjust the solar light intensity and heat radiation has become the focus of recent research.

Nano cesium tungstate is a new material that has been discovered in recent years. It has been widely applied in the field of transparent heat insulation film, in automotive insulation film, building glass membrane, sunshade and heat insulation industries.