Photocatalyst is a kind of photocatalytic function of photosemiconductor materials represented by nanometer titanium dioxide, it is coated on the surface of the substrate, under the action of ultraviolet and visible light, produce strong catalytic degradation function: can effectively degrade toxic and harmful gases in the air;can effectively kill a variety of bacteria, and bacteria or fungi released by the toxin decomposition and harmless treatment;at the same time, it also has the function of removing formaldehyde, deodorizing, anti-fouling, purifying air and so on.

Nano photocatalyst under the light irradiation, the valence band electron is emitted to the conduction band, formed the electrons and holes, and the adsorption on the surface of O2 and H2O, generate superoxide anion free radicals, O2 - and hydroxyl radicals - OH, its free radicals have strong ability of oxidation decomposition can destroy organic matter of C-C bond, C-H bond, C-N bond, C-O bond, O-H bond, N-H bond, break down organic matter into carbon dioxide and water;at the same time, it destroys the cell membrane of bacteria, solidifies the protein of virus, and changes the living environment of bacteria and virus so as to kill bacteria and virus.