Novel Colored Ag Nanopariticle Films

Abstract

Keywords : The focus of this present work is concerned with a novel and facile method for obtaining colored Ag nanoparticle films using an aqueous solution of sulfide as a coloring agent. In the presence of calcium sulfide, the color of the films, initially sliver, changes to pale yellow, deep yellow, purple, blue and green. We found that the key technology in obtaining successful color changes is to control the temperature of the calcium sulfide solution and the dipping time of Ag nanoparticle films in the solution. Our scanning electron microscopy studies indicate that the color of the films depend on the particle size of the surface Ag nanoparticles. This direct and simple method is very practical. One of potential applications of the Ag nanoparticle films is the application as imaging materials.