Chemical precipitation synthesis and optical properties of ZnO/SiO2 nanocomposites

SiO(2) nanowires, made from natural chrysotile, were used to synthesize zinc oxide (ZnO)/SiO(2) composites by chemical precipitation. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy, and Fourier transform infrared. Their optical properties were studied by a ultraviolet-vis spectrophotometer and a fluorescence spectrophotometer. Structural analysis revealed that the crystal size of ZnO crystallites is < 20 nm, and the leached SiO(2) nanowires were amorphous. TEM analysis showed that the size of ZnO particles in SZ8 was mainly in the range from 15 to 20 nm and dispersed uniformly on the surface of SiO(2) nanowires. The photoluminescence spectra showed that ZnO/SiO(2) composites have stronger emitting intensity at the blue-green band than pure ZnO synthesized under the same reaction conditions. Therefore, the composites will be of great interest in the application of luminescence material. The as-prepared ZnO/SiO(2) composites can be used as photocatalysts for waste water treatment because they separate much more easily away from solution.