Photo-catalyst micro-particles and its preparing method, photocatalyst and preparing method and use

This invention relates to a photocatalyst particle with copper-coated nano titanium dioxide and a preparation method thereof, simultaneously relates to a photocatalyst, a preparation method thereof and its application. The preparation method comprises the following steps: adding a metal copper salt, a surfactant, a reductant into a TiO2 sol, and under the UV irradiation, using the nano titanium dioxide as an inducer of the photochemical reaction, generating the metal copper particle through photoreduction reaction in the surface of the nano titanium dioxide, and obtaining the composite material with copper-coated nano TiO2. This invention not only solves the aggregation problem of TiO2 nano particles, but also overcomes the defects that the traditional photocatalyst must act under the illumination conditions because the copper-coated nano TiO2 has long-term metal ions release effects, and has a good antibacterial antifungal function under a dark condition, so that the application is wider.