Characterization and visible light photocatalytic activity of cucurbit[n]urils/CdS-MoS2

Abstract

In order to reduce the impact of CdS photogenerated electron-hole recombination on its photocatalytic performance, a narrow band gap semiconductor MoS2 and organic macromolecular cucurbit[ n]urils (Q[ n]) were used to modify CdS. Q[ n]/CdS-MoS2 ( n=6, 7, 8) composite photocatalysts were synthesized by hydrothermal method. Infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, ultraviolet-visible and photoluminescence spectrum were used to characterize the structure, morphology and optical properties of the products, and the catalytic degradation of the solutions of methylene blue, rhodamine B and crystal violet by Q[ n]/CdS-MoS2 composite catalyst was investigated. The results showed that the Q[ n] played a regulatory role on the growth and crystallization of CdS-MoS2 particles, Q[ n]/CdS-MoS2 ( n=6, 7, 8) formed flower clusters with petal-like leaves, the flower clusters of petal-like leaves increased the surface area and active sites of the catalyst, the Q[ n]/CdS-MoS2 barrier width decreased, the electron-hole pair separation efficiency was improved in the Q[6]/Cds-MoS2. Q[ n] makes the electron-hole pair to obtain better separation and migration. The Q[6]/CdS-MoS2 and Q[7]/CdS-MoS2 have good photocatalytic activity for methylene blue, and the catalytic process is based on hydroxyl radical principle.