High-performance self-cleaning coatings are highly desired by the industry and market.Herein,we synthesized two kinds of ultrafine TiO2 nanocrystals,one is anatase dots with a diameter of 5 nm,and the other is rutile rods with 1.5 nm in width and 7 nm in length.The prepared TiO2 nanocrystal is highly dispersed and stable in water over a month.The coating can be fabricated via a simple spraying method,displaying excellent optical properties and photocatalytic performance on self-cleaning and surrounding environment remediation.The transmittance of glass remains 80％—90％for visible and near-infrared light after 30 cycles of spray.RhB solution(50 mg/L)was applied to the coating surface and form a solid RhB layer was formed,which can be completely removed in 30 min's light irradiation.RhB aqueous solution(100 mL,5 mg/L)was purified after 180 min by a 10 cmx 10 cm glass,on which the coating was sprayed 30 times.The concentrations of formaldehyde and PM 2.5 in surrounding air displayed a significant decrease along 50 min's monitoring.This high-performance coating shows great potential for constructing functional coating on various substrates for industrial applications.