Hierarchical assembly of BiOCl nanosheets onto bicrystalline TiO2 nanofiber: enhanced photocatalytic activity based on photoinduced interfacial charge transfer.

One-dimensional ternary hierarchical heterostructures based on BiOCl nanosheets and bicrystalline TiO2 nanofiber frameworks that consist of anatase-rutile (AR) mixed phase TiO2 nanoparticles were successfully designed by combining the electrospinning technique and solvothermal method. The BiOCl nanosheets were uniformly grown onto the electrospun TiO2 nanofibers, and the density of the secondary BiOCl nanosheets could be controlled by adjusting the precursor concentration. Photocatalytic tests displayed that the ternary BiOCl/TiO2 (AR) hierarchical heterostructures possessed a much higher degradation rate than the bare bicrystalline TiO2 (AR) nanofibers, BiOCl/TiO2 (A) or BiOCl/TiO2 (R) composite. It is mainly attributed to the photogenerated interfacial charge transfer based on the photosynergistic effect of the heterojunctions, which results in the high separation efficiency of photogenerated electron-hole pairs.