Synthesis and characterization of BiOCl‐CoWO 4 nanocomposites with improved photocatalytic activity

We have synthesized novel BiOCl‐CoWO 4 heterostructured nanocomposites through chemical precipitation route with different amount of CoWO 4 using KCl as Cl source at a temperature of 100°C, 4 hours. X‐ray diffraction, transmission electron microscopy, UV‐visible NIR spectroscopy, photoluminescence spectroscopy, N 2 adsorption‐desorption isotherms, and electrochemical impedance spectroscopy were performed to gain the crystal structure, morphology, optical properties, surface area, and charge separation of the prepared photocatalysts. BiOCl‐CoWO 4 composites demonstrated the diffraction peaks of both monoclinic CoWO 4 nanoparticles and tetragonal BiOCl indicating the formation of the nanocomposite. TEM observations have shown that CoWO 4 nanoparticles were deposited on the BiOCl surface. Photoluminescence, fluorescence lifetime study, and Electrochemical impedance spectroscopy responses of materials indicated a good separation efficiency of charge carriers in BiOCl‐CoWO 4 ‐1. The photodegradation efficiency of the prepared materials was assessed by the decomposition of rhodamine B (RhB) dye solution under sunlight irradiation. Among the synthesized materials, the BiOCl‐CoWO 4 ‐1 composite photocatalyst exhibited maximum photocatalytic activity. Thus the resulting heterostructure favored the efficient charge and energy transfer between BiOCl and CoWO 4 nanoparticles across the interface. The investigations from the radical scavenger tests showed that photogenerated h + , O 2 ∙ − , and • OH radicals were involved in the photodegradation of RhB.