Novel Nb₃O₇F/WS₂hybrid nanomaterials with enhanced optical absorption and photocatalytic activity

Coping with increasing environmental issues, niobium oxyfluoride (Nb₃O₇F), as a novel semiconductor, is a promising photocatalyst due to its outstanding electronic and optoelectronic properties. However, the photocatalytic performance of Nb₃O₇F is restricted in practical application due to its weak optical absorption and low carrier separation. In this work, Nb₃O₇F/WS₂hybrids with superior optical absorption and photocatalytic activity have been successfully synthesized by a facile two-step sol-hydrothermal technique. UV-vis spectra show that WS₂not only exhibits enhanced optical absorption in the range of 420-1100 nm but extends the absorption edge, and tends to narrow the band gap of the Nb₃O₇F photocatalyst. Photocatalytic experiments indicate that introducing WS₂into Nb₃O₇F markedly enhances the photocatalytic activity in the degradation of methylene blue dyes under visible-light irradiation. Nb₃O₇F/WS₂photocatalysts exhibit the highest activity with 98.9% decoloration efficiency in 70 min, while pure Nb₃O₇F only achieves 67.9% in the same time and achieves its final decoloration ratio after 150 min. The excellent photocatalytic activity can be directly ascribed to more exposed active sites, higher carrier separation efficiency, and faster carrier transfer. The results may open up a new avenue for the design and preparation of novel and highly efficient photocatalysts.