
Nano grain size tungsten trioxide may be used in the preparation of heat insulation coating so that it may be applied in different places where high heat insulation and high transmittance of visible light are required. It is the photochromic property of WO3 that make it can be applied in the field of heat insulation. In recent years, powder and film are the main research directions of photochromic property of tungsten trioxide. Adopting hydrothermal synthesis method and using sodium tungstate…