Synthesizing tertiary silver/silica/kaolinite nanocomposite using photo-reduction method: Characterization of morphology and electromagnetic properties

Silver was loaded on silica/kaolinite by photo-reduction technique. The present study investigated the effects of the UV irradiation on different characteristics of the particles employing X-ray diffraction (XRD), Fourier-transform infrared spectra (FTIR), UV-vis spectrophotometer (UVS), Brunauer-Emmett-Teller specific surface area method (BETM), zeta potential measurement (ZPM), thermal gravimetric analysis (TGA), scanning electron microscope (SEM), electron dispersive X-ray spectrometer (EDX) and electromagnetic transition instrument (ETI). XRD, FTIR as well as UV absorption methods evidenced that synthesizing procedure was successful under UV irradiation. TGA results demonstrated that the Ag nanoparticles (AgNPs) generated on the silica/kaolinite surface can decrease thermal stability of particles due to proton delocalization of hydroxyl groups and Hofmann-Klemen effect. EDX results showed the presence of chemical elements namely Fe, Al, Si, Mg, K, Ti, Ag, Ca and Fe on the surface of tertiary nanocomposite. The synthesized silver/silica/kaolinite particles were found to have a higher electromagnetic absorption activity compared with silica/kaolinite. As a result, they can be used in polymer-based composites for preparing high performance electromagnetic interference shielding materials. (C) 2012 Elsevier Ltd. All rights reserved.