Hydrothermal synthesis and photocatalytic properties of WO3 nanorods by using capping agent SnCl4·5H2O

Hexagonal tungsten trioxide (h-WO3) nano-rods of different sizes are prepared via hydrothermal synthesis using a capping agent of SnCl4·5H2O. The size of the synthesized WO3 nanoparticles can be controlled by changing concentration of the capping agent SnCl4·5H2O alone. We also investigate microstructures and optical properties of the WO3 nanorods and propose a synthesis mechanism for the nanorods. The photocatalytic activities of the h-WO3 nanorods are evaluated by degradation of Rhodamine-B (RhB), revealing that these nanorods exhibit excellent photocatalytic properties. The capping agent SnCl4·5H2O is found to be critical to governing sizes and properties of the h-WO3 nanorods. Our results demonstrate that functional nano-crystallites with tunable size and morphology can be synthesized via a facile hydrothermal synthesis process by adjusting the concentration of capping agent alone. Such a facile hydrothermal synthesis process should be applicable to other types of nanomaterials and relevant to a wide range of applications.