Novel α-Fe2O3/CdS Cornlike Nanorods with Enhanced Photocatalytic Performance

Various semiconductors have been studied as photocatalysts for photocatalytic degradation of pollutants in aqueous solutions. As one of the promising visible-light-driven semiconductor photocatalysts, alpha-Fe2O3 has advantages of low cost and stability. However, its application is inhibited by the poor separation of photogenerated electron-hole pair. In this work, hybrid structures were prepared to improve the performance of alpha-Fe2O3. CdS nanoparticles were overgrown on the preformed single-crystalline alpha-Fe2O3 nanorods by a simple and mild one-step wet-chemical method, resulting in alpha-Fe2O3/CdS cornlike nanocomposites. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy showed the alpha-Fe2O3/CdS core/shell heterostructure of the nanocomposite with high crystallinity. Furthermore, the cornlike nanocomposites exhibited superior photocatalytic performances under visible light irradiation over the pure alpha-Fe2O3 nanorods and CdS nanoparticles. The photocatalytic activity of the composites is superior to the previously-reported pure alpha-Fe2O3 nanomaterials, and the performance is comparable to both the commercial TiO2 (P25) which is used under UV irradiation and the newly developed alpha-Fe2O3/SnO2 photocatalyst under visible light irradiation. The enhanced performance is associated with the larger surface area of the cornlike structure, the crystalline nature of the materials and the synergy in light absorption and charge separation between alpha-Fe2O3 and CdS. As such, our alpha-Fe2O3/CdS cornlike nanocomposites may be promising to be used as visible-light-driven high-performance photocatalyst.