Ternary structural assembly of BiOCl/TiO2/clinoptilolite composite: Study of coupled mechanism and photocatalytic performance

Novel BiOCl/TiO2/clinoptilolite composite was prepared via a homogeneous precipitation and calcination-crystallization process in this study. Through structural design and spatial assembly, the ternary composite based on clinoptilolite layer as well as the TiO2 nano particles and BiOCl nano sheets was successfully synthesized. The prepared composite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS), N-2 isothermal adsorption-desorption test and electrochemical measurement, respectively. Compared with bare photocatalysts (i.e. TiO2 and BiOCI), the composite exhibited enhanced photoactivity under visible light irradiation towards rhodamine B (RhB). Based on the pseudo-first-order kinetic constants, the photocatalytic performance of BiOCl/TiO2/clinoptilolite composite is around 48 and 11 times higher than that of pure TiO2 and BiOCI, respectively. The enhanced photocatalytic properties of the composite should be attributed to the improved adsorption ability and the formation of the n-p heterojunction between BiOCI and TiO2, which is beneficial to establish the rapid adsorptiondesorption system and promote the efficient separation of the photogenerated electron-hole pairs. The excellent visible-light-driven performance makes the BiOCl/TiO2/clinoptilolite composite possible to be utilized in the field of industrial wastewater treatment. (C) 2019 Elsevier Inc. All rights reserved.