Process for producing crystalline graphite nanofibers

Abstract

A process for producing substantially crystalline graphitic carbon nanofibers comprised of graphite sheets. The graphite sheets are substantially parallel to the longitudinal axis of the carbon nanofiber. These carbon nanofibers are produced by contacting a bulk iron, or an iron:copper bimetallic, or an iron:nickel bimetallic catalyst with a mixture of carbon monoxide and hydrogen at temperatures from about 625° C. to about 725° C. for an effective amount of time.

What is claimed is:  
     
         1 . A process for producing a substantially crystalline graphitic nanofiber wherein at least a portion of which are comprised of graphite sheets that are substantially parallel to the longitudinal axis of the nanofiber, which process comprises reacting a mixture of CO/H 2  in the presence of a catalyst selected from the group consisting of Fe, Fe:Cu bimetallic, and Fe:Ni bimetallic powder catalysts for an effective amount of time at a temperature from about 625° C. to about 725° C.  
     
     
         2 . The process of  claim 1  wherein said nanofibers are characterized as having separate and non-continuous substantially graphite sheets.  
     
     
         3 . The process of  claim 1  wherein said nanofibers are characterized as having continuous substantially graphite sheets forming a non-cylindrical multifaceted tubular structure.  
     
     
         4 . The process of  claim 1  wherein the catalyst is an Fe:Cu bimetallic wherein the ratio of Fe to Cu is from about 1:99 to about 99:1.  
     
     
         5 . The process of  claim 4  wherein the ratio of Fe to Cu is from about 3:7 to about 7:3.  
     
     
         6 . The process of  claim 5  wherein the ration of Fe to Cu is about 7:3 and the temperature is about 650° C.  
     
     
         7 . The process of  claim 1  wherein the catalyst is an Fe:Ni bimetallic wherein the ratio of Fe to Ni is from about 1:99 to about 99:1.  
     
     
         8 . The process of  claim 7  wherein the ratio of Fe to Ni is from about 3:7 to about 7:3  
     
     
         9 . The process of  claim 1  wherein the ratio of CO to H 2  is from about 95:5 to about 5:95.  
     
     
         10 . The process of  claim 9  wherein the ratio of CO to H 2  is from about 80:20 to about 20:80.  
     
     
         11 . The process of  claim 5  wherein the ratio of CO to H 2  is from about 80:20 to about 20:80.  
     
     
         12 . The process of  claim 6  wherein the ratio of CO to H 2  is about 80:20.  
     
     
         13 . The process of  claim 1  wherein the crystallinity of the nanofiber is greater than about 98%.  
     
     
         14 . The process of  claim 5  wherein the crystallinity of the nanofiber is greater than about 98%.  
     
     
         15 . The process of  claim 1  wherein the particle size of the bimetallic powder is from about 0.25 nanometers to about 5 micrometers.  
     
     
         16 . The process of  claim 14  wherein the particle size of the bimetallic powder is from about 2.5 nanometers to about 1 micrometer.  
     
     
         17 . The product produced by the process of  claim 1 .  
     
     
         18 . The product produced by the process of  claim 6 .  
     
     
         19 . The product produced by the process of  claim 12.