Preparation and properties of CdS/Au composite nanorods and hollow Au tubes

Abstract

1-dimensional (1D) metal-semiconductor nano-scale composite superstructures based on Au nanoparticles and CdS nanorods were prepared. The outer surface of CdS nanorods was modified with mercapto-ethylamine (MEA) in advance. With the aid of MEA, dense and uniform Au nanoparticles were deposited onto the external wall of CdS nanorods through in situ chemical reduction of AuCl4 − ions. Those Au nanoparticles induced further electroless deposition and a continuous layer of Au was formed on CdS nanorods. Stable hollow Au tubes were obtained after the inner CdS cores were etched by HCl. UV-Vis, FL, XPS, EDX, TEM and SEM measurements were carried out to characterize the produced materials. The quenching of the defect emission of CdS in CdS-nanorod/Au-nanoparticle hybrid superstructures was detected, which was ascribed to the energy transfer from the exciton of CdS to surface plasma resonance level of Au.