BiOBr@UiO-66 photocatalysts with abundant activated sites for the enhanced photodegradation of rhodamine b under visible light irradiation

In this work, bismuth bromideoxide (BiOBr), a typical visible-light photocatalyst, was coated with Zr-based MOFs (UiO-66) to prepare the BiOBr@UiO-66 photocatalysts with different mole ratios by the solvothermal method. The core-shell BiOBr@UiO-66 photocatalysts with abundant activated sites was obtained due to the modification of UiO-66 on the surface of BiOBr. The structure and properties of the BiOBr@UiO-66 photocatalysts were characterized by several methods. The 30% BiOBr@UiO-66 photocatalysts exhibited the biggest photodegradation rate constant (k = 0.0669 min- 1) for RhB under visible-light irradiation than pure BiOBr (k = 0.0281 min- 1) and UiO-66 (k = 0.0041 min-1). Additionally, the 30% BiOBr@UiO-66 photocatalysts exhibited the enhanced photocatalytic activity and stable recyclability due to the effective electron-hole separation and synergistic effect. The photocatalytic mechanism of the BiOBr@UiO-66 photocatalysts for RhB, which contained a photosensitization process, was discussed with the trapping experiment of active species and the proposed energy band alignments.

Automated summary

In this study, core-shell BiOBr@UiO-66 photocatalysts were successfully prepared, with the 30% mole ratio showing a high photodegradation rate constant, enhanced photocatalytic activity, and stable recyclability. The photocatalytic mechanism for RhB was discussed, highlighting the effective electron-hole separation and synergistic effect of the BiOBr@UiO-66 photocatalysts.