Preparation And Properties Of Photocatalytic Coatings

World Health Organization(NWHO)published the World Health Report clearly stated that formaldehyde is a major threat to human health,cancer risk,and its removal has become very critical to the health of the human body.TiO2 photocatalytic technology because of its strong ability to degrade the mild reaction conditions,lower energy consumption,but due to its own limitations and prone solvent the reunion.This paper study on modicication and dispersion of TiO2,and mix with coating to remove the formaldehyde.Metal-doped nanometer TiO2 powder was prepared by impregnation and sol-gel method,the TiO2 photocatalytic ability was examiened through the degeneration certain density formaldehyde experiment,the structural performance of composite photocatalyst which characterizaed by XRD,UV-Vis,FT-IR and SEM.Effects of TiO2 dispersed in aqueous solution,analyze the type and content of dispersant,pH value,and other factors as a means of dispersing,grinding time,ultrasonic time and ultrasonic power;TiO2 and coating were compounded,different amounts of light,film thickness and other factors affect the degradation rate of formaldehyde.The experimental results showed that:1.The Fe3+、La3+、Cu2+、Ce4+ doped TiO2 photocatalyst could improve photocatalytic performance.Impregnation method in 20℃,dipping time 2h,dipping the pH of the system is calcined at 6,roasting at 500 ℃ 2h,doped with 2.1%Cu2+ catalysts for formaldehyde degradation rate of 76%.And use of a scanning electron microscope(SEM),X-ray diffraction(XRD)and UV-Visible(UV-Vis)absorption spectra the M/TiO2 photocatalyst structure and performance characterization.SEM analysis found,the sample particles are mainly spherical particles,no significant difference in the appearance of the morphology;XRD analysis showed that,the M/TiO2(M = Fe3+、La3+、Cu2+、Ce4+)were antase and the existence of particle size was reduced from 41.081nm to 21.88nm,element doping less impact on the TiO2 structure;UV-Vis absorption spectra showed metal elements doped TiO2 response to the visible light region significantly enhanced.2.When the addition of Cu/TiO2 was 0.10g,dispersant OP-10 was 0.12mL,adjust the system pH value of 8,stirred for 1h,the ultrasonic power is 100W,the ultrasonic time of 40min,the dispersion was the best.3.Cu/TiO2 and coating were compounded by different ways,the results showed that the modified TiO2 first fully dispersed and then adding into the coating was better.When the Cu/TiO2 was 2.5%,the formaldehyde degradation was the best.When the coating was put under the xenon lamp,the formaldehyde degradation achieved to 70%,the photocatalytic coating with certain reusable performance.