Search

As a decoration method, coupling a photocatalyst with semiconductor quantum dots has been proven to be an efficient strategy for enhanced photocatalytic performance. Herein, a novel BiOCl nanosheet decorated with Bi 2 O 3 quantum dots (QDs) was first synthesized by a facile one-step in situ chemical deposition method at room temperature. The as-prepared materials were characterized by multiple means of analysis. The Bi 2 O 3 QDs with an average diameter of about 8.0 nm were uniformly embedded on the surface of BiOCl nanosheets. The obtained Bi 2 O 3 QDs/BiOCl exhibited significantly enhanced photocatalytic performance on the degradation of the rhodamine B and ciprofloxacin, which could be attributed to the band alignment, the photosensitization effect and the strong coupling between Bi 2 O 3 and BiOCl. In addition, the dye photosensitization effect was demonstrated by the monochromatic photodegradation experiments. The radical trapping experiments and the ESR testing demonstrated the type II charge transfer route of the heterojunction. Finally, a reasonable photocatalytic mechanism based on the relative band positions was discussed to illustrate the photoreaction process. These findings provide a good choice for the design and potential application of BiOCl-based photocatalysts in water remediation., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Two-dimensional vertically aligned Bi 2 O 3 nanosheets over carbon paper (CP) were prepared via an in situ growth approach. Bi 2 O 3 /CP exhibits a robust photocatalytic activity, as well as renewability and flexibility. With Rhodamine B and 2,4-dichlorophenol used as target pollutants, the rate constant of Bi 2 O 3 /CP was 3.72 × 10 -3 min -1 and 6.93 × 10 -3 min -1 under visible-light irradiation for 2 h, respectively. The improved activity was attributed to the synergistic effects of the hierarchical structure of Bi 2 O 3 and the conductive substrate, CP; the former provided efficient catalytic sites for the pollutants and absorbed more of the light scattered among the nanosheets, while the latter is beneficial to the photogenerated electron transfer., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Herein, defect intrinsic hexagonal boron nitride (h-BN) quantum sheets (QS) and bismuth oxide (Bi 2 O 3 ) QS were prepared from bulk materials by ball milling and solvent stripping, respectively. The h-BN/Bi 2 O 3 heterostructure was fabricated via a facile self-assembly method. The structure and performance of samples were systematically characterized. As expected, the layered h-BN QS is tightly coated on the surface of Bi 2 O 3 QS in a face-to-face stacking structure and interconnected by strong interface interactions. The introduction of h-BN QS can significantly enhance the separation efficiency of the photogenerated carriers of h-BN/Bi 2 O 3 . The experimental results show that the photocatalytic activity of h-BN/Bi 2 O 3 is markedly improved. The first-order reaction rate constant of the 3wt%-BN/Bi 2 O 3 sample is 3.2 × 10 -2 min -1 , about 4.5 times that of Bi 2 O 3 QS. By means of the active species capture test, it is found that the main oxidation species are holes (h + ), followed by hydroxyl radicals (˙OH). Based on the surface charge transfer characteristics, the photogenerated carrier transfer and separation efficiency can be improved by coupling h-BN and a Bi 2 O 3 semiconductor to the Schottky heterojunction, and the strong interaction between heterogeneous interfaces also enhances the surface catalytic reaction efficiency, which improves dramatically the photocatalytic performance., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)