Hydrothermal synthesis of sphere-like BiOCl using sodium lignosulphonate as surfactant and its application in visible light photocatalytic degradation of rodamine B

The BiOCl-SL was prepared by a simple hydrothermal reaction between Bi(NO₃)₃·5H₂O and KCl using sodium lignosulfonate (SL) as a structure-directing agent. The standard tetragonal structure of the BiOCl has been confirmed by X-ray powder diffraction. The scanning electron microscopy results revealed that a suitable amount of SL is favorable for the formation of hollow sphere-Like BiOCl. The fourier transform infrared spectroscopy (FT-IR) of the BiOCl-SL showed the BiOCl samples have been cleaned thoroughly, and the following photocatalytic experiment will not be affected by SL. In comparison with the pure BiOCl, the UV–Vis diffuse reflectance spectroscopy (UV–Vis-DRS) of the BiOCl-SL showed a red shift of absorption edge. The Brunauer–Emmett–Teller surface area measurement indicated that the surface area of BiOCl-SL is much bigger than that of pure BiOCl. The photocatalytic activity of BiOCl was tested on the degradation of Rodamine B (RhB) under visible light irradiation, and the result showed that the BiOCl-SL-0.3 had excellent photocatalytic activity for RhB after visible light irradiation for 2 h.