Bi ₂O ₃ quantum-dot decorated nitrogen-doped Bi ₃NbO ₇ nanosheets: In situ synthesis and enhanced visible-light photocatalytic activity

The Bi ₂O ₃ quantum dots decorated nitrogen doped Bi ₃NbO ₇ nanosheets (Bi ₂O ₃/N-Bi ₃NbO ₇) were successfully synthesized via a facile in situ hydrothermal process as a straightforward protocol. The peony-like N-Bi ₃NbO ₇ hierarchical architectures decorated with surface enrichment of Bi ₂O ₃ quantum dots were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectra, UV-vis diffuse reflectance spectrum and photoluminescence spectra. The as-prepared Bi ₂O ₃/N- Bi ₃NbO ₇ heterostructures exhibited higher photocatalytic activities in the decomposition of model pollutants under visible-light irradiation than N-Bi ₃NbO ₇ nanosheets in the absence of any expensive metal components and co-catalysts, which could be attributed to the enhanced light absorbance multiple reflections in the heterostructures, the enhanced photosensitizing effect of the surface enriched Bi ₂O ₃ quantum dots and the strong interaction between Bi ₂O ₃ and N-Bi ₃NbO ₇. Furthermore, the Bi ₂O ₃/N-Bi ₃NbO ₇ heterostructures exhibited strong durability that may be ascribed to the high hydrothermal stability of the flower-like structure and the inhibition of Bi ₂O ₃ leaching owing to its tight chemical bonding with N-Bi ₃NbO ₇ nanosheets.