Preparation Of Air Purifying Flexible Materials In Situ Synthesis At Low Temperature

In recent years, along with the rapid development of domestic economy and hiking living standards, people in china have paid more attention to the indoor decoration. The use of decorative materials, furniture and household products almost invariably gives rise to the presence of volatile organic compounds (VOCs) in indoor air. In the view of advantage in terms of large specific surface area, easy-fabricating, rich in resource and low cost, the photocatalystic air-purificating fabric prepared for the degradation of indoor VOCs has became the hotspot of investigation.In this study, the situ synthesis method at low temperature had been applied to prepare the air purifying fiber materials. Cotton fabric was chosen as the support for TiO2 photocatalysts. First, tetraethoxysilane(TEOS) layers, the mesoporous transition layers with large specific surface area, were coated on cotton fabric. Then the nano-size TiO2 layers were coated on at low temperature in situ synthesis. The produced cotton fabric has high photocatalytic degradation ability without any pollution. The photocatalysts on the fabric were characterized by TGA, SEM, EDS, AFM, XRD and Raman Spectra, respectively. Their photocatalytic degradation for formaldehyde were tested in static system. The main content of this work were presented as follow:1. The nano-TiO2 was coated directly to the cotton fabric surface at low temperature in situ synthesis, the effect of different synthesis parameters on the growth of the different properties of TiO2 had been tested. The result of SEM, EDS showed that a layer of particles covered the surface of cotton fabric smoothly, and existed Ti,O elements were confirmed. With the further analysis by XRD and Raman Spectra, the crystal structures of photocatalyst over the cotton fabric were ensured of anatase type, and the average size of TiO2 particles is about 16 nm. Tensile strength of cotton fabric indicated that the warp strength decreased 20.07% and the weft strength decreased 16.07%. The photocatalytic activity was examined by the air purifying material under ultraviolet light photocatalytic formaldehyde in static system. The result showed that in static system the formaldehyde reduction with photocatalytic oxidation is 100%.2. The cotton fabric was immersed in the TEOS solution, and the intermediate protective layer of SiO2 was pretreated to the surface of cotton fabric in situ synthesis. On which the air purifying material, nano-TiO2 was coated by the secondary in situ synthesis. In the same way, the result of SEM, EDS and AFM showed the state of the surface of cotton fabric, and Si, Ti and O elements were observed. The pattern of XRD and Raman Spectra showed that the crystal structures of photocatalysts over the cotton fabric are also of anatase type, and the average size of TiO2 particles is about 10 nm. Tensile strength indicated that the warp strength increased 20.82% and the weft strength increased 21.10%. The photocatalytic activity was examined by the air purifying material under ultraviolet light in static system. The result showed that in static system the formaldehyde reduction with photocatalytic oxidation is almost the same with the former one. The antioxidant capacity and flexibility of cotton fabric were both improved.The air purifying material prepared has a good photocatalytic activity. And it is expected to be applied to real life by improving its preparation process, which would create more social and economic profits.