Preparation method of titanium oxide coated diamond powder

The invention discloses a preparation method of titanium oxide coated diamond powder, and belongs to the field of diamond powder surface treatment. The method comprises the following steps: putting pretreated diamond powder and Ti (SO4) 2 into ethanol, and magnetically stirring to obtain a Ti (SO4) 2 ethanol saturated solution containing the diamond powder; the mixed solution is put into a low-temperature constant-temperature box, magnetic stirring is conducted after the mixed solution is cooled to the ultralow temperature ranging from-50 DEG C to-100 DEG C, the solubility of Ti (SO4) 2 in ethyl alcohol is greatly reduced, Ti (SO4) 2 is crystallized and separated out on the surface of diamond powder, the mixed solution is filtered and separated at the ultralow temperature, and diamond powder with the surface coated with a Ti (SO4) 2 film is obtained; and the diamond powder coated with the Ti (SO4) 2 film is heated to 500-600 DEG C, so that Ti (SO4) 2 is decomposed into TiO2, and the diamond powder coated with