Nanoparticles, nanosponges, methods of synthesis, and methods of use

摘要

We disclose novel metallic nanoparticles coated with a thin protective carbon shell, and three-dimensional nano-metallic sponges; methods of preparation of the nanoparticles; and uses for these novel materials, including wood preservation, strengthening of polymer and fiber/polymer building materials, and catalysis.

主权项

1. A method for making metallic-core carbon-shell nanoparticles, said method comprising the steps of:
(a) impregnating biological fibers with a solution of metal ions in an aqueous or non-aqueous solvent; (b) removing the solvent, while leaving at least some of the metal ions impregnated in the fibers; and (c) heating the metal-ion-impregnated fibers in an inert atmosphere or in a vacuum to a temperature that carbonizes at least some of the fibers, that does not vaporize most of the carbon, that reduces at least some of the metal ions to metal particles in a zero oxidation state, and that causes a carbon shell to form around and to completely enclose most of the zero-oxidation-state metal particles; wherein no reducing agent is present during the reduction step, other than said biological fibers themselves; and wherein the reduction of the metal ions to metal particles in a zero oxidation state, and the formation of the carbon shell around the zero-oxidation state metal particles occur simultaneously.