Process of dry milling particulate materials

Abstract

Graphene produced by media ball milling has very small particle size, a relatively high surface area and unique aspect ratios. It is uniquely suited to make nano-composites or coating by coating or admixing other particles. Metals or metal oxides can be coated or formed into composites with the high surface area, relatively low aspect ratio graphene. If the added particles are larger than the graphene, they are coated with graphene, and if they are about the same approximate size, a nano-composite forms. The nanocomposites are useful for producing electrodes, especially for battery and supercapacitor applications.

What is claimed is: 
     
         1 . A process of dry milling particulate materials, wherein at least one of the particulate materials is a layered material, in the presence of a non-layered material, to obtain a composition wherein the layered material is exfoliated and wherein the non-layered material is composited with the exfoliated material, the exfoliated material having a particle size of 10 microns by 5 nm thick, or less, and wherein the dry milling is controlled by controlling the surface energy of the milling media in addition to controlling the hardness of the milling media. 
     
     
         2 . The process as claimed in  claim 1  wherein the non-layered material is selected from the group consisting essentially of:
 i. a particulate metal and, 
 ii. a particulate metal oxide. 
 
     
     
         3 . The process as claimed in  claim 1  wherein the layered material is graphite. 
     
     
         4 . The process as claimed in  claim 1  wherein the milling media has a surface energy essentially equivalent to the surface energy of the layered material. 
     
     
         5 . The process as claimed in  claim 1  wherein the milling media has a hardness on the Brinell Scale in the range of 3 to 100. 
     
     
         6 . The process as claimed in  claim 1  wherein the exfoliated material has an aspect ratio of greater than about 25. 
     
     
         7 . The process as claimed in  claim 1  wherein the exfoliated material has an aspect ratio of from 5 to 200. 
     
     
         8 . The process as claimed in  claim 1  wherein the exfoliated material has a size in the range of from 50 nm to 10 microns. 
     
     
         9 . The process as claimed in  claim 1  wherein the exfoliated material has a thickness of from 1 nm to 5 nm. 
     
     
         10 . The process as claimed in  claim 1  wherein the milling media is plastic material. 
     
     
         11 . The process as claimed in  claim 10  wherein the plastic is selected from the group consisting essentially of:
 i. polymethylmethacrylate, 
 ii. polycarbonate, 
 iii. polystyrene, 
 iv. polypropylene, 
 v. polyethylene, 
 vi. polytetrafluoroethylene, 
 vii. polyethyleneimide, 
 viii. polyvinylchloride, 
 ix. polyamine-imide, and, 
 x. alloys of any of i. to ix. 
 
     
     
         12 . The process as claimed in  claim 2  wherein the particulate metals are selected from the group consisting essentially of:
 i. silicon, 
 ii. tin, 
 iii. iron, 
 iv. magnesium, 
 v. manganese, 
 vi. aluminum, 
 vii. lead, 
 viii. gold, 
 ix. silver, 
 x. titanium, 
 xi. platinum, 
 xii. palladium, 
 xiii. ruthenium, 
 xiv. copper, 
 xv. nickel, 
 xvi. rhodium, and, 
 xvii. alloys of any of i. to xvi. 
 
     
     
         13 . The process as claimed in  claim 2  wherein the particulate metal oxides are selected from the group consisting essentially of oxides of:
 i. silicon, 
 ii. tin, 
 iii. iron, 
 iv. magnesium, 
 v. manganese, 
 vi. aluminum, 
 vii. lead, 
 viii. gold, 
 ix. silver, 
 x. titanium, 
 xi. platinum, 
 xii. palladium, 
 xiii. ruthenium, 
 xiv. copper, 
 xv. nickel, 
 xvi. rhodium, and, 
 xvii. alloys of any of i. to xvi. 
 
     
     
         14 . The process as claimed in  claim 1  wherein the particulate non-layered material has a size less than 100 microns. 
     
     
         15 . The process as claimed in  claim 1  wherein the particulate are metal carbides. 
     
     
         16 . The process as claimed in  claim 1  wherein the particulate materials are metal nitrides. 
     
     
         17 . A product when produced by the process of  claim 1 . 
     
     
         18 . An electrode produced from the product as claimed in  claim 17 . 
     
     
         19 . A catalyst produced from the product as claimed in  claim 17 . 
     
     
         20 . A coating produced from the product as claimed in  claim 17 . 
     
     
         21 . An electronic component manufactured from the product as claimed in  claim 17 . 
     
     
         22 . A thermally conductive component manufactured from the product as claimed in  claim 17 . 
     
     
         23 . A process of dry milling particulate materials, wherein at least one of the particulate materials is a layered material, in the presence of a particulate material selected from the group consisting of i. ceramic, ii. glass, and iii. quartz, to obtain a composition wherein the layered material is exfoliated and wherein the particulate material is coated with the exfoliated material, the exfoliated material having a particle size of 500 nanometers or less, and wherein the dry milling is controlled by controlling the surface energy of the milling media in addition to controlling the hardness of the milling media. 
     
     
         24 . A process of dry milling particulate materials, wherein at least one of the particulate materials is a layered material, in the presence of a particulate material selected from the group consisting of i. ceramic, ii. glass, and iii. quartz, to obtain a composition wherein the layered material is exfoliated and wherein the particulate material is coated with the exfoliated material, the exfoliated material having a particle size of 10 microns or more, and the wherein the dry milling is controlled by controlling the surface energy of the milling media in addition to controlling the hardness of the milling media. 
     
     
         25 . A composition of matter comprising particles composited with graphene wherein the particles are selected from the group consisting essentially of metal particles, and metal oxide particles, wherein the metal and metal oxide particles have a size of 100 microns or smaller. 
     
     
         26 . A composition of matter as claimed in  claim 25  wherein the metal and metal oxide particles have a size of 100 microns or less. 
     
     
         27 . A composition of matter as claimed in  claim 25  wherein the metal and metal oxide particles have a size of 10 microns or less. 
     
     
         28 . A composition of matter as claimed in  claim 25  wherein the metal and metal oxide particles have a size of 1 micron or less. 
     
     
         29 . A composition of matter as claimed in  claim 25  wherein the graphene is less than 5 nm thick. 
     
     
         30 . A composition of matter as claimed in  claim 25  wherein the graphene is a monolayer thick. 
     
     
         31 . A composition of matter as claimed in  claim 25  wherein the oxygen content of the graphene is ten atomic weight percent or less. 
     
     
         32 . A composition of matter as claimed in  claim 25  wherein the metal is selected from the group consisting essentially of iron, magnesium, cobalt, molybdenum, and lead. 
     
     
         33 . A composition of matter as claimed in  claim 25  wherein the metal oxide is selected from the group of oxides consisting essentially of iron oxide, magnesium oxide, cobalt oxide, molybdenum oxide, and lead oxide. 
     
     
         34 . A composition of matter as claimed in  claim 25  wherein the size of the graphene particle is less than 5 microns. 
     
     
         35 . A composition of matter as claimed in  claim 25  wherein the surface area of the graphene is greater than about 300 m 2 /g BET. 
     
     
         36 . A composition of matter as claimed in  claim 25  wherein the metal particles are larger than the graphene composited with them. 
     
     
         37 . A composition of matter as claimed in  claim 25  wherein the metal particle are essentially the same size as the graphene they are combined with. 
     
     
         38 . A composition of matter as claimed in  claim 25  that is a nanocomposite. 
     
     
         39 . An electrode manufactured from the composition of  claim 25 . 
     
     
         40 . A battery comprising at least one electrode as claimed in  claim 39 . 
     
     
         41 . A capacitor comprising an electrode as claimed in  claim 39 .