Tungsten oxide powder may be applied for producing thermal insulation masterbatch, which will have excellent weather resistance, high temperature resistance, high transparency, high heat insulation and environmental protection. Tungsten oxide is also an inorganic electrochromic material. At present, the market application of electrochromic materials is limited to small-sized products such as automatic anti-glare automobile rearview mirrors and aircraft portholes. In order to realize the wide-area use of electrochromic materials in the field of building curtain walls, it is necessary to…