Supercapacitors with Carbon Nanostructure Electrodes

Abstract

Supercapacitors having electrodes made of high-surface-area carbon nanostructures coated with a smooth and conformal submonolayer-to-multilayer thin metal films and their method of manufacture are described.

1 . A supercapacitor comprising:
 a first electrode comprising carbon nanostructures coated with a contiguous atomic layer of noble metal atoms, said first electrode being saturated with an electrolyte solution and in electrical contact with a first current collector;   a second electrode comprising carbon nanostructures coated with a contiguous atomic layer of noble metal atoms, said second electrode being saturated with an electrolyte solution and in electrical contact with a second current collector;   and a separator layer which electrically insulates the first electrode from the second electrode.   
     
     
         2 . The supercapacitor of  claim 1  wherein the carbon nanostructures are selected from the group consisting of fullerenes, single-walled carbon nanotubes, multi-walled carbon nanotubes, and carbon nanohorns. 
     
     
         3 . The supercapacitor of  claim 1 , wherein the atomic layer is selected from the group consisting of a submonolayer, monolayer, and bilayer of noble metal atoms. 
     
     
         4 . The supercapacitor of  claim 1 , wherein the atomic layer consists of either three or four layers of noble metal atoms. 
     
     
         5 . The supercapacitor of  claim 1 , wherein the noble metal consists of ruthenium. 
     
     
         6 . An aggregate of carbon nanohorns coated with a contiguous atomic submonolayer, monolayer, or bilayer of ruthenium atoms. 
     
     
         7 . A supercapacitor comprising:
 a first electrode comprising carbon nanostructures coated with a contiguous atomic layer of noble metal atoms, said first electrode being saturated with an electrolyte solution and in electrical contact with a first current collector;   a second electrode comprising carbon nanostructures coated with a contiguous atomic layer of noble metal atoms, said second electrode being saturated with an electrolyte solution and in electrical contact with a second current collector;   and a separator layer which electrically insulates the first electrode from the second electrode.