Synthesis of Nanoparticles Using Ethanol

Abstract

The present disclosure relates to methods for producing nanoparticles. The nanoparticles may be made using ethanol as the solvent and the reductant to fabricate noble-metal nanoparticles with a narrow particle size distributions, and to coat a thin metal shell on other metal cores. With or without carbon supports, particle size is controlled by fine-tuning the reduction power of ethanol, by adjusting the temperature, and by adding an alkaline solution during syntheses. The thickness of the added or coated metal shell can be varied easily from sub-monolayer to multiple layers in a seed-mediated growth process. The entire synthesis of designed core-shell catalysts can be completed using metal salts as the precursors with more than 98% yield; and, substantially no cleaning processes are necessary apart from simple rinsing. Accordingly, this method is considered to be a “green” chemistry method.

1 . A core-shell nanoparticle comprising:
 an atomically ordered metal core, comprising a first metal; and   a shell comprising a second metal, wherein there is no migration metal of atoms between the atomically ordered metal core and the shell.   
     
     
         2 . The core-shell nanoparticle of  claim 1 , wherein the core-shell nanoparticle has an average particle size diameter of between about 1 nm and about 10 nm. 
     
     
         3 . The core-shell nanoparticle of  claim 2 , wherein the atomically ordered core comprises ruthenium or palladium. 
     
     
         4 . The core-shell nanoparticle of  claim 3 , wherein the shell comprises a layer of platinum with a thickness of about one to two platinum atoms. 
     
     
         5 . The core-shell nanoparticle of  claim 3 , wherein the atomically ordered core comprises ruthenium and the shell comprises a palladium layer with a thickness of about one to two palladium atoms. 
     
     
         6 . A catalyst for the hydrogen evolution reaction comprising the nanoparticle of  claim 1 . 
     
     
         7 . A catalyst for the hydrogen oxidation reaction comprising the nanoparticle of  claim 1 . 
     
     
         8 . A catalyst for the oxygen reduction reaction comprising the nanoparticle of  claim 1 .