Synthesis of a novel one-dimensional BiOBr-Bi4O5Br2 heterostructure with a high quality interface and its enhanced visible-light photocatalytic activity

Herein, a novel rod-like BiOBr-Bi4O5Br2 heterostructure with a high quality interface was synthesized by calcining a BiOBr precursor in air at 450 degrees C for 2 h. Bi4O5Br2 nanosheets grew on the rod-like BiOBr made of nanosheets. The content of the loaded Bi4O5Br2 can be controlled by adjusting the concentration of glucose during the preparation of BiOBr precursors. The photocatalytic activity of the as-made products was evaluated by the degradation of rhodamine B (RhB). The results show that the BiOBr-Bi4O5Br2 heterostructure displays outstanding photocatalytic activity as compared to the pure phase BiOBr and Bi4O5Br2, and 100% RhB (20 mg L-1) can be degraded within 5/10 min under solar/visible-light irradiation. This enhanced photocatalytic performance is ascribed to the synergistic effect of the suitable band alignment of BiOBr and Bi4O5Br2 and the formation of a high quality interface between BiOBr and Bi4O5Br2. Radical scavenger experiments prove that the photogenerated holes and O-center dot(2)-play a key role in the photo-degradation process. This study would offer a simple route for the design and fabrication of one-dimensional junction structures with high interface quality for photocatalytic applications.