Preparation of hollow cone-like ZnO/CoFe2O4 heterostructures and their photocatalytic properties

Heterostructures of hollow cone-like ZnO/CoFe₂O₄ nanocomposites (NPs) are successfully fabricated by a two-step hydrothermal route with the assistance of Si substrate as the template. The material structure, composition, morphology as well as the magnetic property have been investigated via scanning electron microscopy, transmission electron microscopy, an X-ray diffractometer and a vibrating sample magnetometer. Photocatalytic performance was also examined. The NPs have a bone-structure of ZnO coated with CoFe₂O₄ NPs, which have a cone-like feature with a diameter of 200-300 nm and 200 nm in the hole with a large surface-to-volume ratio. It is the special heterostructures that bring about a novel high surface area leading to highly efficient photo-degradation in visible light and recyclability because of ferromagnetism. The degradation of tetracycline of NPs reaches 81.03% in 120 min.