Facile solvothermal synthesis of BiOCl–TiO2 heterostructures with enhanced photocatalytic activity

Abstract

BiOCl–TiO₂ heterostructures with different Bi to Ti molar ratios were synthesized via a facile one-pot solvothermal process. The as-synthesized BiOCl–TiO₂ heterostructures included TiO₂ nanoparticles deposited on the surface of BiOCl nanoplates. X-ray photoelectron spectroscopy results revealed the TiO₂ of BiOCl–TiO₂ heterostructures doped with Bi³⁺, reduced the band gap energy of the sample. The photocatalytic efficiencies were evaluated by degradation of methylene blue dye under simulated sunlight illumination. Results indicated that the BiOCl–TiO₂ heterostructures with Bi : Ti = 1 : 3 exhibited the highest photocatalytic efficiency, which is 73.5 times and 8.5 times higher than that of single phase BiOCl and TiO₂, respectively. In addition, the radical species involved in the degradation process have been investigated by scavenger experiments. Finally, a new mechanism for the photocatalytic action of the BiOCl–TiO₂ heterostructures was put forward.