In situ synthesis and photocatalytic performance of WO3/ZnWO4 composite powders

Abstract

The WO₃/ZnWO₄ composite powders were synthesized through an in situ reaction process with tunnel structure K₁₀W₁₂O₄₁·11H₂O filiform crystallites used as a precursor. At first, Zn²⁺ ions was intercalated into the K₁₀W₁₂O₄₁·11H₂O crystal by exchanging K⁺ ions, then these Zn²⁺-exchanged samples were transformed into WO₃/ZnWO₄ composite powders during heat-treatment. The formation reaction and structure of these samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectrometer (EDS). The results showed that the WO₃/ZnWO₄ composite powders consisted of WO₃ nanoparticles and ZnWO₄ nanorods. Photocatalytic experiments exhibited an excellent photocatalytic performance for the degradation of methylene blue (MB) and the degradation efficiency was about 95% after 70 min under simulated sunlight.