Preparation Of Core-shell Nano-composites And Its Applications

The unique characteristics of the core-shell nano-materials were widely used in various aspects. It not only played a role in the core-shell materials, but also played its role as the shell application of functional materials. Wherein, the magnetic iron oxide as the core could be composited easily by other function materials, because of its magnetic and the larger surface area. Anatase titanium dioxide was often used as a shell, because it had better photocatalytic properties and environmentally friendly. In order to increase the catalytic properties and play its unique properties of the core-shell materials, a layer of silver material was usually composited on their surface. In addition, the paper also studied the different materials as the core-shells were composited with silver nano-composite materials to study their photocatalytic properties.Firstly, the large-size polystyrene microspheres were synthesized by a simple microemulsion method. After that, the composite microspheres with the polystyrene microspheres as the core and titanium dioxide as the shell were the sol-gel method. The hollow titanium dioxide was synthesized by the calcination. TiO2@Ag hollow microspheres were synthesized by precious metal silver nanoparticles coated on the surface of the hollow titania which as a template. In order to study the photocatalytic properties of the composite materials, Rhodamine6G and Methylene Blue as analog sources, and explore its degradation mechanism.The magnetic Fe3O4nano-materials with a uniform particle size and the larger surface area were prepared by hydrothermal method. The core-shell magnetic Fe3O4@TiO2composites were prepared by sol-gel method with magnetic Fe3O4as a template. Fe3O4@TiO2@Ag nano-composites were prepared by the reduction of silver nitrate with Fe3O4@TiO2as a core. The possible synthesis mechanism was discussed. And methylene blue and R6G substrate were acted as acanalog pollution to explore the photocatalytic properties of the composites.The PS@TiO2core-shell microspheres were prepared by a sol-gel method with the polystyrene microspheres as templates, PVP as dispersant and the tetrabutyl titanate as the titanium source. The PS@TiO2@Ag core-shell composite microspheres were prepared with the PS@TiO2microspheres as templates and glucose as reductant. In order to examine the photocatalytic ability of these two core-shell composites, organic dye methylene blue was degraded by photocatalytic degradation experiments.