A kind of economical, environment-friendly and controllable synthesis of Nb3O7F nanowalls and their photocatalytic properties

Niobium oxyfluoride (Nb3O7F) with excellent optoelectronic properties holds great promise for applications in photocatalysis, hydrogen production and solar cell. However, how to avoid volatile, pungent & corrosive hydrofluoric acid (HF) in Nb3O7F production is always an important issue. Here, we demonstrate a facile hydrothermal approach to prepare Nb3O7F nanowalls without adding HF. Different characterization tools have been used to analyze the phase, microstructure and photocatalytic properties. The calculated UV-vis and XPS spectra show that the bandgap (Eg) of Nb3O7F nanowalls is about 3.03 eV and valence-band maximum (VBM) is about 1.82 eV. The photocatalytic experiments show that Nb3O7F nanowalls with good stability and repeatability exhibit higher visible-light activity for degrading methylene blue (MB) than commercial P25.