Effect of Calcination Temperature on the Properties of Visible-Light-Active TiO2 Self-Cleaning Surfaces

• Main Authors: Ninuk-Liana Lay, 賴玉玲
• Other Authors: Yu-Min Yang
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/56532250502170713881

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 97 === Transparent and self-cleaning surfaces in this work are defined as surfaces with visible-light-active, antireflective, and self-cleaning properties. They were prepared by electrostatic layer-by-layer (ELbL) assembly technique using MPT-428 particles, which are commercial Fe-doped TiO2 photocatalyst, and SiO2 nanoparticles. On the other hand, self-cleaning surfaces in this work were prepared by spin coating method using BA-PW 25 particles, which are commercial nitrogen-doped TiO2 photocatalyst. All the thin films were calcinated with four different calcination temperatures under air to study the effect of calcination temperature on the characteristics of the thin films. The experimental results revealed that the transparent and self-cleaning surfaces fabricated by ELbL assembly have linear growth behavior, high transmittance, low refractive index and uniform surface morphology. The photocatalytic activity and surface wetting sustainability of all the thin films were evaluated by monitoring the absorbance of methylene blue adsorbed thin film during visible light illumination and by measuring the change of water contact angle with dark storage time, respectively. The best photocatalytic activity and surface wetting sustainability of the transparent and self-cleaning surfaces can be realized by the highest number of bilayer and the lowest calcination temperature. On the other hand, the self-cleaning surfaces indicated visible-light-active photocatalysis but nonuniform surface morphology. Experimental results also revealed that the calcination temperature had insignificant effect on the photocatalytic activity and surface wetting sustainability of self-cleaning surfaces. However, the self-cleaning surfaces can maintain water contact angle less than 10o even after storing in the dark place for 20 days.