Fabrication of ZnWO₄-CdS heterostructure photocatalysts for visible light induced degradation of ciprofloxacin antibiotics

ZnWO₄-CdS heterostructure photocatalysts have been successfully synthesized by hydrothermal method with assembling CdS on the surface of ZnWO₄. The obtained composite photocatalysts were characterized by X-ray diffraction, transmission electron microscopy, Raman, thermo-gravimetric analysis, UV-vis diffuse reflectance spectroscopy, photoluminescence and photocurrent measurement. The results show that the interface between ZnWO₄ and CdS is well formed, and the CdS nanoparticles are uniformly distributed onto ZnWO₄ nanorods which could facilitate charge transfer and reduce recombination of photo-generated electrons and holes. Compared with pure ZnWO₄ and CdS, the as-prepared heterostructure photocatalysts exhibit excellent photostability and photodegradation ability of ciprofloxacin (CIP) under visible light irradiation.