Preparation and characterization of nano-sized zinc oxide loaded on hollow SiO2 and study of photocatalytic activity

In recent years, synthesized ZnO with different morphologies have considerable interest for scientific research due to their importance in mesoscopic physics and their potential applications. ZnO with various morphologies have been prepared such as nanospheres, one-dimensional structure (nanorods, nanowires and nanotubes), fractal shape (flower and prism) etc. The photocatalytic applications of various types of ZnO structures have been reported so far. In photocatalysis and surface chemistry, charge trapping extends the lifetime of photo generated electrons and holes and decreases their recombination rate. This is a desired effect because it enhances the quantum yield of the photocatalyst. In the other way, surfaces and defects associated with the surface have a major impact on the physical properties of polycrystals, when they get a few nanometers in size since the surface-to-volume ratio is large. The research of core/shell particles and hollow spheres with special physical and chemical properties have attracted great interest due to their potential applications in photonic crystals, In this work, we report synthesis of the nanosized ZnO particles on hollow silica matrix using zinc acetate and tetraethoxysilane as zinc and silica precursors. Characterization of the as prepared material, nanosized ZnO on the hollow silica was performed before and after selective removal of ZnO nanoparticles by scanning electron microscopy, energy dispersive X-ray spectroscopy (EDAX) and transmission electron microscopy (TEM). The results indicated that the SiO2/ZnO mixed hallow nanoparticles were Simit braed-like shape with average size of 20 nm and enhanced photocatalytic activity of the samples evaluated by degrading of the methyl orange (MO) under irradiation of UV light.