What is the photocatalyst?
Photocatalyst absorb and convert light energy into useful chemical energy, which can decompose a wide range of organic pollutants in the environment. Nevertheless, photocatalyst won・t decrease or deactive itself in this photocatalytic process.
What is the stuff of photocatalyst?
Fine TiO2 (titanium dioxide) nanoparticle is the main stuff of photocatalyst due to its chemical stability, nontoxicity, and high photocatalytic reactivity.
The structure of TiO2
TiO2 is a N type semiconductor. According to the molecule structure, TiO2 compound has an anatase (A-), rutile(R-) or brookite (B-) structure of which the anatase structure has the highest photocatalytic activity.
The functions of TFC・s photocatalyst
1. Sterilize (germs and mildew)
2. Decompose a wide range of organic compounds including odorous components into harmless compounds such as CO2 and H2O to purify air and water.
3. Decontaminate and self-clean the materials attached on the surface.
The principles of photocatalyst
Light absorbed by the TiO2 excites the electrons from the valence band to the conductive band of TiO2, resulting in the separation of electrons (e-) and holes (h+). These electrons and holes can react with oxygen (O2) and water (H2O) to generate O2- and OH free radicals. These free radicals having high reactivity can decompose the organic compounds by the redox reaction.
The test of TFC・s photocatalyst 1. Particle size
The particle size is the most important aspect related to the photocatalytic reactivity. When the particle size of the TiO2 is bigger than 100 nanometer, the photocatalytic performance is much less than that of nanograde TiO2.
TFC・s photocatalyst was detected by the MICROTRAC UPA-150 and HORIBA LB-500 particle analyzer to measure the particle size. TFC・s photocatalyst is a nanograde product, which average particle size ranges from 50~70 nm.
2. Sterilization test
The staphylococcus sterilization test of TFC・s photocatalyst was carried out by TTU bioengineering department. 99.5% germs were killed on TFC・s photocatalytic film after 300 Lux, one hour exposed under common daylight lamp.
3. Responsive test of light wavelength
A SHIMADZU UV-2401PC UV-VIS Recording Spectrophotometer was used to measure the wavelength absorbing responds. All of the TiO2 photocatalyst made by other companies absorbs light in ultraviolet range, but the TFC・s photocatalyst absorbs the light from ultraviolet to visible range. So TFC・s photocatalyst may operate the photocatalytic process under the ultraviolet and visible light.
Where can we use TFC・s photocatalyst?
The photocatalyst can be used in surface of any substrate that can be in touch with light, for example, the surfaces inside and outside of buildings, cars, electric equipments, furniture and etc.
