Synthesis of Bi/BiOCl/PVP hybrids with efficient photocatalytic activity

Bi/BiOCl/PVP hybrids were synthesized via a one-pot solvothermal method. Its comprehensive analysis used combination of techniques such as x-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), x-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance (DRS) and photoluminescence spectroscopies (PL). Both the the light absorption capacity and charge separation efficiency of BiOCl were improved by bismuth deposition and PVP modification. The bandgap narrowing in Bi/BiOCl/PVP resulted from the band edge red-shift, which was demonstrated by experimental observations and theoretical calculations. The prepared Bi/BiOCl/PVP hybrids showed much higher efficiency than TiO2 (Degussa P25) in removal of Rhodamine B (RhB) under visible light irradiation, and acidic condition was superior in RhB degradation. Holes and peroxyl radicals were proved as the predominantly active oxidant. The proposed Bi/BiOCl/PVP hybrid opened a new strategy for the photoactivity enhancement of BiOCl.