Correlation between the band gap, elastic modulus, Raman shift and melting point of CdS, ZnS, and CdSe semiconductors and their size dependency

Sulfur vacancy-tailored NiCo2S4 nanosheet arrays for the hydrogen evolution reaction at all pH values

Sulfur vacancy-tailored NiCo₂S₄ nanosheet arrays as efficient electrocatalysts for the hydrogen evolution reaction at all pH values.

Novel Nb3O7F/WS2 hybrid 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/WS2 hybrids with superior optical absorption and photocatalytic activity have been successfully synthesized by a facile two-step sol-hydrothermal technique. UV-vis spectra show that WS2 not 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 WS2 into Nb3O7F markedly enhances the photocatalytic activity in the degradation of methylene blue dyes under visible-light irradiation. Nb3O7F/WS2 photocatalysts 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.

CNTs-Modified Nb3O7F Hybrid Nanocrystal towards Faster Carrier Migration, Lower Bandgap and Higher Photocatalytic Activity

Novel semiconductor photocatalysts have been the research focus and received much attention in recent years. The key issues for novel semiconductor photocatalysts are to effectively harvest solar energy and enhance the separation efficiency of the electron-hole pairs. In this work, novel Nb₃O₇F/CNTs hybrid nanocomposites with enhanced photocatalytic activity have been successfully synthesized by a facile hydrothermal plus etching technique. The important finding is that appropriate pH values lead to the formation of Nb₃O₇F nanocrystal directly. A general strategy to introdue interaction between Nb₃O₇F and CNTs markedly enhances the photocatalytic activity of Nb₃O₇F. Comparatively, Nb₃O₇F/CNTs nanocomposites exhibit higher photodegradation efficiency and faster photodegradation rate in the solution of methylene blue (MB) under visible-light irradiation. The higher photocatalytic activity may be attributed to more exposed active sites, higher carrier migration and narrower bandgap because of good synergistic effect. The results here may inspire more engineering, new design and facile fabrication of novel photocatalysts with highly photocatalytic activity.

Finite size and length effects on bandgap of CdSe nanorods

E _g(D, L) function of CdSe nanorods versus L and D.

Size- and temperature-dependent Young's modulus and size-dependent thermal expansion coefficient of thin films

Surfaces of nanomaterials play an essential role in size-dependent material properties.