A solvent-assisted route for coating polystyrene colloids with Ag and the corresponding hollow Ag spheres

A novel ethylene dichloride solvent-assisted route has been successfully developed to coat uniformly polystyrene colloids with Ag and prepare the corresponding hollow spheres. In this route, by corroding and swelling the PS colloid surface with ethylene dichloride, Ag seeds are synthesized directly in and on the surface layer of core, not only the surface functionalization is avoided, but also may enhance the combination of core and seeds. The ethylene dichloride concentration is crucial for the coating results. The coverage, thickness, and roughness of the Ag shell can be effectively controlled by varying the amount of HCHO during the seeding growth process, and the as-prepared composites can crystallize into ordered structure. This coating route is facile and versatile, and apt to coat PS colloids with other metal and prepare the corresponding hollow metal spheres.