▎ 摘　　要

CdS nanoparticles (NPs) on the edges of reduced graphene oxide (RGO) sheets are prepared. Carboxyl groups at the periphery of RGO sheets are converted to amine groups and a free-radical polymerization initiator is anchored to the RGO sheets. Poly(2-vinyl pyridine) (P2VP) brushes on RGO sheets are synthesized by in situ free-radical polymerization. Upon the addition of cadmium ions into the dispersion of RGO-P2VP nanocomposites in methanol, P2VP brushes form complexes with Cd2+, and CdS NPs protected by P2VP can be prepared upon the addition of sodium sulfide. A transmission electron microscope (TEM), Fourier Transform Infrared absorption spectra (FT-IR) and thermogravimetric analysis (TGA) are employed to characterize the composites. TEM results provide direct evidence for the location of CdS NPs at the periphery of RGO sheets. Fluorescence results indicate that there is a strong interaction between CdS NPs and RGO sheets. The synthesized composites show strong optical limiting ability. (C) 2013 Elsevier B.V. All rights reserved.