Grafting BiOCl nanosheets onto TiO2 tubular arrays to form a hierarchical structure with improved photocatalytic performance

A TiO2/BiOCl composite with a hierarchical structure was constructed by grafting BiOCl nanosheets onto a film of TiO2 nanotube arrays. The structure and morphology were characterised using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-vis diffuse reflection spectroscopy, and Raman spectroscopy. The activity of the composite photocatalyst for the photodegradation of methyl orange and pentachlorophenol was higher than that of either single-phase TiO2 or BiOCl. The improved photodecomposition performance can be mainly attributed to the enhanced separation efficiency of photo-induced electrons and holes, both at the interface and in the two semiconductors. The proposed grafting strategy for the formation of this hybrid photocatalyst can also be applied to other semiconductor candidates resulting in improved photo-electrochemical properties.