Low-temperature molten salt process for the synthesis of NaBi7P2O16 nano-plates with excellent photocatalytic activity

Abstract

In this work, a facile low-temperature molten salt route for the synthesis of NaBi7P2O16 nano-plates has been demonstrated without needing any templates or surfactants, in which Na3PO4·12H2O was employed to act as the medium, as well as the reactant. The crystal structure and morphology of the products were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The experiments suggested that the Na3PO4·12H2O content has great effect on the microstructure of NaBi7P2O16. The pure rhombic phase of NaBi7P2O16 with plate-like shape can be obtained at a molar ratio of 1:10 between Bi(NO3)3·5H2O and Na3PO4·12H2O. The photocatalytic activity of NaBi7P2O16 nano-plates was investigated by the degradation of rhodamine B (RhB) and methyl orange under ultraviolet light irradiation. NaBi7P2O16 nano-plates exhibited better photocatalytic activity than that of commercial P25 photocatalyst, which was attributed to the more positive of valence band and the large negative charge of PO43− ions in NaBi7P2O16. Moreover, NaBi7P2O16 nano-plates possess desirable photochemical stability, which favors practical application for removing contaminants in water. This work provides a green way for synthesizing high-performance photocatalysts.