One-pot preparation of Bi/BiOF/Bi2O2CO3 Z-scheme heterojunction with enhanced photocatalysis activity for ciprofloxacin degradation under simulated sunlight

Abstract

To improve the photocatalytic activity of BiOF under simulated sunlight irradiation, a ternary Bi-based Z-scheme heterojunction of Bi/BiOF/Bi₂O₂CO₃ nanosheets were prepared using one-pot hydrothermal technique, where N, N-dimethylformamide was used as carbon source for Bi₂O₂CO₃ and reductant for metal Bi, bismuth nitrate was employed as Bi source and NaF was used as F source. The photocatalytic activity of Bi/BiOF/Bi₂O₂CO₃ was improved greatly towards ciprofloxacin degradation with the reaction kinetic constant of 0.0649 min⁻¹, which was 7 and 3.5 times to that of BiOF and Bi₂O₂CO₃, respectively. The improved photocatalytic activity was ascribed to the surface plasmon resonance effect of metal Bi and the synergistic effects of BiOF/Bi₂O₂CO₃ Z-scheme heterojunction, which facilitated the migration of the photogenerated electron and inhibited the recombination of photogenerated e⁻/h⁺ pairs. The degradation mechanism and charge transfer pathway were confirmed. This work expands the application of BiOF-based photoactive materials in environmental field.