Synthesis, characterization, and visible photocatalytic performance of Zn2GeO4 nanobelts modified by CdS quantum dots

摘要

Zn2GeO4 nanobelts modified by CdS quantum dots (Zn2GeO4/CdS) were prepared successfully by chemical bath deposition. The novel photocatalyst was characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance spectroscopy. It was found that Zn2GeO4/CdS consisted of uniform rhombohedral phase Zn2GeO4 nanobelts with highly dispersed cubic phase CdS quantum dots, and the Zn2GeO4/CdS exhibited strong visible light absorption at about 510 nm. The photocatalytic activities of the catalysts were evaluated by the discoloration of Rhodamine B under visible light illumination and were compared with that of pure Zn2GeO4 nanobelts. The results suggested that the composite photocatalyst had much higher photocatalytic activities than pure Zn2GeO4 nanobelts under irradiation of visible light. Meanwhile, no obvious deactivation of Zn2GeO4/CdS was observed after the three recycles experiments in photodegradation of RhB. The possible mechanism of visible light photocatalytic degradation is also proposed.