The Studies On Sn²+ Doped Nano-TiO₂ Functional Coatings

Because of special characters, nano-technology has been a field of growing interest in recent years. Nano-composite coating exhibiting many function and high performance,which can be manufactured by adding appropriate nano-particles into polymer and this can be applied to many fields. As an eco-material,TiO₂ plays more and more important role in the environment contamination disposal for the characterization of nontoxicity, high photo-catalytic ability , stabilization of physical and chemical property, cheap, et al.Especialy,nano-TiO₂ coatings for paint is a major development in research direction. But the performance of nano-TiO₂ is needed to be improved. In this article, metallic ion doping is a effective method to enhance the photocatalytic degradation and antibacterial activity.In this article, environmental protection type nano-TiO₂ modified coatings were prepared. Such factors as calcinations temperature, pH were investigated for photodegradation of methyl orange. Meanwhile the doping amount of TiO₂/Sn²⁺, the initial concentration of illumination time have important effect on the degradation of formaldehyde which were determined. The results of degrading formaldehyde by nano-sized coatings demonstrate that Sn²⁺ co-doped TiO₂ nanocoatings can treat formaldehyde in air effectively. The degrading methyl orange can reach 62.21% when the calcinations temperature is 300℃.When the particle content of TiO₂/Sn²⁺is 9%,degradation rate of the coating on formaldehyde after 12hours is average 76.94%.In a certain extent,the greater the initial concentration of formaldehyde, the effect on the degradation of formaldehyde is better. The samples were characterized by X-ray diffraction (XRD) and UV-Vis optical property analysis etc.Though calculating the amount of bacteria, the nano-TiO₂ modified coatings antibacterial performance was studied in the nanometer doped powder with different content which is 5% TiO₂,5% TiO₂/Sn²⁺,7% TiO₂/Sn²⁺,9% TiO₂/Sn²⁺ respectively using. The results suggested nano-titanium dioxide content of the larger,better bactericidal effect, and 9% when the largest and bactericidal rate of 91.95% can be achieved. Meanwhile antibacterial performance is a slowly process with increasing time for TiO₂/Sn²⁺ coatiings. In addition to, temperature has little influence on antibacterial performance so that coatings can be applied well in any conditions.