Preparation and enhanced visible-light photocatalytic performance of TiO2/CdS hierarchical film

The construction of a hierarchical structure is considered an effective way to improve the photocatalytic efficiency in its practical application. In this paper, a TiO2/CdS hierarchical film has been fabricated on a Ti substrate by simple successive ionic layer adsorption and reaction between CdCl2 and Na2S solution. The samples are characterized by x-ray diffraction, UV–vis diffuse reflectance spectroscopy, x-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and transmission electron microcopy. It is revealed that a combination of TiO2 hierarchical film and CdS nanoparticles effectively reduced the recombination rate of electrons and holes, resulting in enhanced photocatalytic properties. Phenol solution underwent the highest photocatalytic degradation of 98.7% after 120 min of visible light exposure, and it was above 90% after ten cycles. Noticeably, the TiO2/CdS-5 hierarchical film exhibits excellent photocatalytic activity and reusability. This significant improvement lays the foundation for the development of new hierarchical functional materials that enable efficient photocatalytic applications.