Hydrothermal Synthesis of Urchin-like Bi2S3 Nanostructures for Superior Visible-light-driven Cr(VI) Removal Capacity

摘要

In this work, large amounts of urchin-like Bi2S3 nanostructures assembled from radially oriented nanorods were prepared by a simple hydrothermal method. The as-prepared Bi2S3 nanostructures possess an orthorhombic crystal structure with a high crystallinity. More importantly, the obtained Bi2S3 nanostructures are spherical architectures composed of large quantities of nanorods with highly active sites. This attractive architecture can provide a large active surface area for photo-catalysis. The photodegradation of Cr(VI) under visible light irradiation indicated that 95% of Cr(VI) was degradated within 30 min using the as-prepared Bi2S3 nanoparticle as a photo-catalyst. Further investigations revealed that the pH value of the solution has a significant effect on the photocatalytic reduction ability as well. Significantly, the kinetic constant of urchin-like Bi2S3 nanostructures for Cr(VI) degradation is about 100 times that of Bi2S3 nanoflowers and commercial P25. Furthermore, the photocurrent of urchin-like Bi2S3 nanostructures is still higher than that of Bi2S3 nanoflowers. We believed that the urchin-like Bi2S3 nanostructures are promising materials for Cr(VI) photoreduction.