Tuning of morphology of Ag nanoparticles in the Ag/polyaniline nanocomposites prepared by γ-ray irradiation

Ag/polyaniline (PANT) nanocomposites were prepared by two different methods using gamma-ray irradiation. The morphology of the Ag nanoparticles in the nanocomposites was followed by transmission electron microscopy (TEM). In one of the method (Method 1), Ag/ PANI nanocomposites were prepared by the following sequential steps. PVP-stabilized Ag colloids were prepared by gamma-irradiation, aniline was added and oxidatively polymerized. Method II involved the preparation of Ag/PANI nanocomposites by oxidative polymerization of aniline-stabilized Ag colloids prepared by gamma-irradiation. The average size of PVP-stabilized Ag sphere-type nanoparticles was 13 nm. The morphology of Ag nanoparticle in Ag/PANI nanocomposites prepared by Method I was sphere-type. On the other hand, the morphology of aniline-stabilized Ag nanoparticle prepared by gamma-irradiation was a hexangular-type one. Size of aniline-stabilized Ag nanoparticles was found to depend on the weight ratios of aniline-to-Ag ions used in the preparation. The paper discusses the changes in the morphology of Ag nanoparticles in the Ag/PANI nanocomposites with the method of preparation, source of protection and polymerization. (c) 2006 Elsevier B.V. All rights reserved.