Flash carbon coating on active surfaces, methods of manufacture thereof and articles comprising the same
Disclosed herein is a method comprising mixing an electroactive particle with a carbonaceous material to form a particle mixture that comprises a carbon coated particle; subjecting the carbon coated particle to a pulsed voltage between parallel plate electrodes or between rolls of a roll mill; and converting the carbon coated particle to a graphite coated particle via localized Joule heating. Disclosed herein too is an apparatus comprising a mixing device that is operative to mix an electroactive particle with a carbonaceous material to form a particle mixture that comprises a carbon coated particle; and a device for applying a pulsed voltage to the particle mixture; where the applying of the pulsed voltage is conducted when the particle mixture is located between opposing plate electrodes or between opposing rolls of a roll mill; where the device for applying the pulsed voltage converts the carbon coated particle into a graphite coated particle.
1. A method comprising:
mixing an electroactive particle with a non-conductive carbonaceous material to form a particle mixture that comprises a coated particle comprising the electroactive particle having a coating consisting of the carbonaceous material;
subjecting the coated particle to a pulsed voltage between parallel plate electrodes or between rolls of a roll mill to convert the coated particle to a graphite coated particle via localized Joule heating.
2. The method of claim 1 , where the pulsed voltage is 10 to 200 volts.
3. The method of claim 1 , where the pulsed voltage has a pulse duration of 5 to 50 milliseconds.
4. The method of claim 1 , where the particle mixture further comprises a solvent.
5. The method of claim 1 , where the parallel plate electrodes comprise a refractory material.
6. The method of claim 5 , where the refractive material is copper, graphite or tungsten.
7. The method of claim 1 , where the graphite coated particle comprises an amorphous layer and a graphite layer.
8. The method of claim 7 , where the amorphous layer is disposed between the electroactive particle and the graphite layer.
9. The method of claim 1 , where the graphite coated particle comprises only a graphite layer disposed on the electroactive particle.
10. The method of claim 1 , further comprising transporting the particle mixture while applying the pulsed voltage to the particle mixture.
11. The method of claim 1 , further comprising discharging the particle mixture from a mixing device to the parallel plate electrode.
12. The method of claim 1 wherein the carbonaceous material is selected from the group consisting of polymers, carbon containing gases, aliphatic or aromatic hydrocarbons with or without oxygen atoms, organic polymers or combinations thereof.
13. A method comprising:
mixing an electroactive particle with a carbonaceous material to form a particle mixture that comprises a carbon coated particle;
subjecting the carbon coated particle to a pulsed voltage between parallel plate electrodes or between rolls of a roll mill; and
converting the carbon coated particle to a graphite coated particle via localized Joule heating where the particle mixture is discharged from a mixing device to a moving sheet which is a current collector.