Process for nano-scaled graphene plates

Abstract

A process for producing a nano-scaled graphene plate. The material comprises a sheet of graphite plane or a multiplicity of sheets of graphite plane. The graphite plane is composed of a two-dimensional hexagonal lattice of carbon atoms and the plate has a length and a width parallel to the graphite plane and a thickness orthogonal to the graphite plane with at least one of the length, width, and thickness values being 100 nanometers or smaller. The process for producing nano-scaled graphene plate material comprises the steps of: a). partially or fully carbonizing a precursor polymer or heat-treating petroleum or coal tar pitch to produce a polymeric carbon containing micron- and/or nanometer-scaled graphite crystallites with each crystallite comprising one sheet or a multiplicity of sheets of graphite plane; b). exfoliating the graphite crystallites in the polymeric carbon; and c). subjecting the polymeric carbon containing exfoliated graphite crystallites to a mechanical attrition treatment to produce the nano-scaled graphene plate material.

1 - 5 . (canceled)  
     
     
         6 . A process for producing a nano-scaled graphene plate material comprising the steps of: 
 a). either partially or fully carbonizing a precursor polymer or heat-treating petroleum or coal tar pitch to produce a polymeric carbon containing micron- and/or nanometer-scaled graphite crystallites with each crystallite comprising one sheet or a multiplicity of sheets of graphite plane;    b). exfoliating said graphite crystallites in said polymeric carbon; and    c). subjecting said polymeric carbon containing exfoliated graphite crystallites to a mechanical attrition treatment to produce said nano-scaled graphene plate material.    
     
     
         7 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said precursor polymer, petroleum or coal tar pitch is in a fiber form.  
     
     
         8 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said precursor polymer is selected from the group consisting of polyacrylonitrile and its copolymers or derivatives, phenol formaldehyde and its copolymers or derivatives, rayon and its derivatives, cellulose and its derivatives, and combinations thereof.  
     
     
         9 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said step of carbonizing or heat-treating comprises a heat treatment at a temperature in the range of 300° C. to 2,500° C.  
     
     
         10 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said step of carbonizing or heat-treating comprises a heat treatment at a temperature in the range of 300° C. to 1,000° C.  
     
     
         11 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said step of exfoliating comprises a chemical treatment that includes an interlayer chemical attack, intercalation, foaming, heating and/or cooling.  
     
     
         12 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said step of exfoliating comprises contacting said polymeric carbon with an oxidizing agent selected from the group consisting of nitric acid, potassium chlorate, chromic acid, potassium permanganate, potassium chromate, potassium dichromate, perchloric acid, phosphoric acid, sulfuric acid, trifluoroacetic acid, organic acid, and mixtures thereof.  
     
     
         13 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said mechanical attrition treatment comprises a ball milling treatment of said polymeric carbon.  
     
     
         14 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said mechanical attrition treatment comprises operating a high-energy planetary ball mill.  
     
     
         15 . The process for producing nano-scaled graphene plate material as defined in  claim 6 , wherein said polymeric carbon produced in step (a) is pulverized to become small particle or short fiber segment forms prior to step (b).  
     
     
         16 - 19 . (canceled)