Preparation of silver nanoparticles using chitosan suspensions

Silver/chitosan nanocomposites were prepared by using basic chitosan suspension as a stabilizer and as a reductant in the absence of other chemicals. The size and distribution of the resulting nanocomposite were strongly dependent on the concentration of chitosan and sodium hydroxide. UV-vis spectra and analytical electron microscopy (AEM) revealed the presence of silver/chitosan nanocomposites. In addition, Ag nanoparticles were obtained by annealing silver/composites at 600 degrees C. These nanoparticles were characterized by field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectrometry (EDS). The FESEM indicated that the size of a majority of the Ag nanoparticles ranged between 10 and 150 mm. A change in the nanoparticles to porous-like nanostructures was observed when the composite feeding amount was increased, the annealing tithe prolonged, and the reaction temperature elevated. (C) 2007 Elsevier B.V. All rights reserved.