Sonochemical synthesis and characterization of magnetic separable Fe3O4/Ag composites and its catalytic properties

A Fe3O4/Ag composite, with high efficiency in the degradation of rhodamine B was synthesized through a simple sonochemical method. These composites were obtained from sonication of Ag(NH3)(2)(+) and (3-aminopropyl)triethoxysilane (APTES)-coated Fe3O4 nanoparticles solution at room temperature in ambient air for 1 h. A formation mechanism was proposed and discussed. This sonochemical method is attractive since it eliminated the use of any reductants, which is necessary to transform the Ag+ to the Ag-0. In comparison to high temperature or high pressure experimental processes, this method is mild, inexpensive, green and efficient. The M-H hysteresis loop of these Fe3O4/Ag composite microspheres indicates that the composite spheres exhibit superparamagnetic characteristics at room temperature. Furthermore, these composites can be recycled six times by magnetic separation without major loss of activity. Thus, these Fe3O4/Ag composites can be served as effective and convenient recyclable catalysts for practical application. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.