Synthesis, characterization, and dispersion behavior of ZnO/Ag nanocomposites

ZnO/Ag nanocomposites that are composed of quasi-spherical nanoparticles with diameters of several nanometers have been successfully generated by a two-step liquid precipitation method. The as-prepared ZnO/Ag nanocomposites were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HRTEM). The dispersion behaviors of the ZnO/Ag nanocomposites in isopropanol with using nonionic dispersants such as stearic acid, PVP K17, and PVP K30 were investigated by conventional sedimentation method, dynamic light scattering method (DLS) and TEM observation. Both the PVP K17 and PVP K30 could disperse the ZnO/Ag nanoparticles effectively in isopropanol. It is proposed that the nonionic dispersants could form absorbed PVP molecule layers on the surfaces of the ZnO/Ag nanoparticles, prohibiting their agglomeration and enhancing their dispersion stability in isopropanol. This work is helpful for further investigating the potential applications of ZnO/Ag nanocomposites in the fields of medical plastics and sterilization. (C) 2012 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.