Treating Particles

Abstract

A method of treating particles by disaggregating, deagglomerating, exfoliating, cleaning, functionalising, doping, decorating and/or repairing said particles, in which the particles are subjected to plasma treatment in a treatment chamber containing a plurality of electrodes which project therein and wherein plasma is generated by said electrodes which are moved during the plasma treatment to agitate the particles.

1 . A method of treating particles by disaggregating, deagglomerating, exfoliating, cleaning, functionalising, doping, decorating and/or repairing said particles, in which the particles are subjected to plasma treatment in a treatment chamber containing a plurality of electrodes which project therein and wherein plasma is generated by said electrodes which are moved during the plasma treatment to agitate the particles. 
     
     
         2 . A method according to  claim 1  in which the particles treated are graphite particles. 
     
     
         3 . A method according to  claim 2  in which the graphite particles are exfoliated to produce graphene containing particles, preferably graphene nanoplatelets (GNPs). 
     
     
         4 . A method according to  claim 1  in which the particles treated are nano-particles. 
     
     
         5 . A method according to  claim 4  in which the nanoparticles are carbon nano-particles, preferably fullerenes such as carbon nanotubes (CNTs), or graphene containing nanoparticles such as GNPs. 
     
     
         6 . A method according to  claim 1  in which glow discharge plasma is generated by the electrodes. 
     
     
         7 . A method according to  claim 1  in which plasma is formed in a localised region around each electrode. 
     
     
         8 . A method according to  claim 1  in which a gas or gaseous mixture is introduced into the chamber to sustain the plasma, in which said gas or gaseous mixture is introduced from each electrode. 
     
     
         9 . A method according to  claim 1  in which the electrodes are moved at a speed which is varied during the course of the plasma treatment so as to control the interaction between the plasma generated by the electrodes and the particles. 
     
     
         10 . A method according to  claim 1  in which at least a portion of the treatment chamber is rotated thereby causing the electrodes to move during the plasma treatment. 
     
     
         11 . Apparatus for treating particles in a method according to  claim 1  including a treatment chamber containing a plurality of electrodes which project therein, each electrode for generating a plasma, in which said electrodes are moveable to agitate particles disposed in the treatment chamber. 
     
     
         12 . Apparatus according to  claim 11  in which at least a portion of the treatment chamber is rotatable thereby to cause the electrodes to move thereby agitating particles disposed in the treatment chamber. 
     
     
         13 . Apparatus according to  claim 12  in which the treatment chamber is rotatable around a longitudinal axis, and the electrodes are radially disposed around the longitudinal axis. 
     
     
         14 . Apparatus according to  claim 11  in which three or more, and preferably between 3 and 20, electrodes project into the treatment chamber. 
     
     
         15 . A method of repairing defects in fullerene or graphene containing nanoparticles in which said nanoparticles are subjected to a plasma treatment wherein plasma is formed in a carbon containing gas or gaseous mixture including a carbon containing gas, the carbon containing gas being present in an amount sufficient to repair defects in said nanoparticles. 
     
     
         16 . A method according to  claim 15  in which the plasma treatment is a plasma enhanced chemical vapour deposition (PECVD) process. 
     
     
         17 . A method according to  claim 15  in which the carbon containing gas is a hydrocarbon, an alcohol or a halocarbon. 
     
     
         18 . A method according to  claim 17  in which the carbon containing gas is methane, methanol, or carbon tetrachloride. 
     
     
         19 . A method according to  claim 18  in which the plasma is formed in pure methane or in a gaseous mixture which consists essentially of methane. 
     
     
         20 . A method according to  claim 15  in which the nanoparticles are CNTs or GNPs.