Synthesis, characterization and application of CdS/ZnO nanorod heterostructure for the photodegradation of Rhodamine B dye

Abstract

CdS/ZnO photocatalyst were prepared by two steps via hydrothermal and photochemical method for the photodegradation of Rhodamine B (RhB) dye. The structural and morphological features of both pure ZnO nanorod and CdS/ZnO heterostructures were carefully characterized using various techniques including UV/Vis spectroscopy, XRD, SEM, EDX and EIS. The UV/Vis absorption spectra revealed that absorption performance of heterostructure is extended toward the visible light regions. Photocatalytic activity of both ZnO nanorod and CdS/ZnO heterostructures were investigated for the photodegradation of RhB dye. It was found that CdS/ZnO heterostructure prepared with 30 min light illumination shows the best photocatalytic efficiency than the one at 15 min and pure ZnO nanorod. The better and enhanced photocatalytic efficiency of CdS/ZnO heterostructure was ascribed to the high charge separation efficiency. The maximum photocatalytic efficiency of 85% was achieved within 8 h with the CdS/ZnO-30 min photocatalyst. This work revealed that composite such as CdS/ZnO heterostructure has better photocatalytic efficiency that pure ZnO nanorod. Keywords: Photocatalyst, Nanorod, Photodegradation, Rhodamine B, Hydrothermal