Photocatalyst material has been serious attention in recent years, due to it has oxidative decomposition reaction and the hydrophilic phenomenon. If  the material is coated on the window glass in a large area, it is possible to increase the reaction area, and thus will bring more effective decomposition of pollutants or harmful gases; in addition, its super-hydrophilic phenomenon can make the glass always remain clean. Photocatalyst as a nano-scale transition metal oxide, the outdoor illumination of UV (ultraviolet) and indoor lighting which below 400nm band can stimulate it to produce catalytic reactions in general, without the need for additional waste of energy.

 

Titanium dioxide is an optical catalyst which is the most widely used with the quite good photocatalytic effect. Single titanium oxide film is typically transparent, which the penetrate power can even reach 80%; however, the penetrate power and reflection rate are completely reduced after being heated, on the contrary, the transmittance decreased with the increasing of film thickness. Experiment has found out that after doping tungsten trioxide, the surface of the composite film had a metal reflective shiny, which the reflection rate is greater than that of pure titanium dioxide film. Furthermore, after the heat treatment, the crystalline of tungsten oxide will have an effect with the more amount of oxygen, so that the original hazel film will become more transparent, and the less metallic luster. When it heated to 450°C, the entire film turned white, so, without affecting the optical properties of the premise of the film, to control the amount of tungsten oxide doped with an appropriate amount is necessary.

 

As an emerging nanotechnology come together with the chemical mechanisms of photo-catalysis, the photo-catalytic titanium dioxide-tungsten trioxide offers a new meaning of remediation and degradation on volatile organic compounds in the aqueous and airs streams. Photo-catalysis technologies are about to create new markets. The advantageous actions including biological contamination, self clean buildings, deodorizing, anti-bacterial action and anti-fogging resolving cleaning action. Photo-catalysis applied technologies now have been proving to be effective in many industrial applications in fact, the photo-catalysis technology has been widely applied in many fields to ease our chores and to cut our maintenance cost. Examples are the effect of purify NOx in the air, and metropolitan to reduce heat gain in the buildings result in super-hydrophilicity and vaporization heat of photo-catalysis.  

 

Since it is easy to generate oxygen vacancies between Ti and W, after doped with tungsten trioxide, the system itself will have soothing changed, like improving efficiency of charge separation, expanding the scope of its spectral response, increasing the available light frequency energy ect.; after providing the light energy, the bonded with water molecules is stimulated, and produce a hydrophilic, thereby enhance the photocatalytic activity of the original titanium dioxide photocatalyst.

 

Now that, since the titanium dioxide-tungsten trioxide photocatalyst composite film has been created, we can image that it maybe lead to a revolution of photocatalyst. In the future, we shall leave in a cleaner and fresher environment because of the burden using of photocatalytic products.