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The pure anatase phase nanometer TiO2 powder were prepared by sol–gel method using tetrabutyl titanate, absolute ethyl alcohol and glacial acetic acid as starting materials, and using anhydrous potassium pyrophosphate and sodium pyrophosphate as dispersants. TEM micrographs and XRD results show that the particle-size distribution range is between 25 and 40 nm. The pure anatase phase nanometer TiO2 powder exhibit good ultraviolet shielding properties in a wavelength range of 280~380nm and good permeability in the visible region, which can be used to prepare ultraviolet shielding materials in low cost and high performance.