Systems and methods for formation and harvesting of nanofibrous materials
View Patent ↗A system that receives nanomaterials, forms nanofibrous materials therefrom, and collects these nanofibrous materials for subsequent applications. The system is coupled to a chamber that generates nanomaterials, typically carbon nanotubes produced from chemical vapor deposition, and includes a mechanism for spinning the nanotubes into yarns or tows. Alternatively, the system includes a mechanism for forming non-woven sheets from the nanotubes. The system also includes components for collecting the formed nanofibrous materials. Methods for forming and collecting the nanofibrous materials are also provided.
1. A method for forming a nanofibrous non-woven sheet, the method comprising:
synthesizing a volume of free-flowing nanotubes from a carbon source and a plurality of catalyst particles;
depositing the volume of free-flowing nanotubes continually onto a moving surface;
transporting the volume of nanotubes continually deposited onto the moving surface away from a point of deposition;
applying pressure onto the plurality of nanotubes against the surface, so as to compact the nanotubes into a non-woven sheet of intermingled nanotubes;
directing the non-woven sheet toward an area independent of the moving surface for collection;
putting a material onto one side of the non-woven sheet to prevent the non-woven sheet from bonding to itself; and
collecting the non-woven sheet from the moving surface by winding the sheet about an axis substantially transverse to a direction of movement of the sheet.
2. A method as set forth in claim 1 , wherein the step of depositing includes continuously depositing the nanotubes onto the surface within an airtight environment.
3. A method as set forth in claim 1 , wherein the step of transporting includes moving the nanotubes away in a direction substantially transverse to a direction of deposition.
4. A method as set forth in claim 1 , wherein the step of applying includes forcing the nanotubes to move between the surface and a rolling mechanism.
5. A method as set forth in claim 1 , wherein the step of directing includes lifting the non-woven sheet from the surface so that it is substantially disengaged for subsequent harvesting.
6. A method as set forth in claim 1 , wherein, in the step of putting, the material is a non-magnetic material so as to prevent the non-woven sheet from sticking strongly to the material.
7. A method as set forth in claim 1 , wherein the step of collecting includes controlling a rate of winding, so as to avoid compromising the integrity of the non-woven sheet.
8. A method as set forth in claim 1 , further including, prior to the step of depositing, generating an electrostatic field through which the nanotubes can be directed to permit substantial alignment of the nanotubes.
9. A method for forming a nanofibrous non-woven sheet, the method comprising:
synthesizing a volume of free-flowing nanotubes from a carbon source and a plurality of catalyst particles;
depositing the volume of free-flowing nanotubes continually onto a moving surface;
transporting the volume of nanotubes continually deposited onto the moving surface away from a point of deposition;
directing the non-woven sheet toward an area independent of the moving surface for collection; and
collecting the non-woven sheet from the moving surface.
10. A method as set forth in claim 9 , wherein the step of removing includes lifting the non-woven sheet from the surface so that it is substantially disengaged for subsequent harvesting.
11. A method as set forth in claim 9 , further including, prior to the step of depositing, generating an electrostatic field through which the nanotubes can be directed to permit substantial alignment of the nanotubes.
12. A method for forming a nanofibrous sheet, the method comprising:
synthesizing, from a carbon source and a plurality of catalyst particles, a volume of free-flowing nanotubes;
continually depositing the volume of free-flowing nanotubes onto a moving surface;
transporting the volume of nanotubes continually deposited onto the moving surface away from a point of deposition;
allowing the plurality of nanotubes deposited onto the surface to compact into a non-woven sheet of intermingled nanotubes; and
collecting the non-woven sheet.
13. A method as set forth in claim 12 , further including, prior to the step of depositing, generating an electrostatic field through which the nanotubes can be directed to permit substantial alignment of the nanotubes.
14. A method for forming a nanofibrous sheet, the method comprising:
synthesizing, from a carbon source and a plurality of catalyst particles, a volume of free-flowing nanotubes;
continually depositing the volume of free-flowing nanotubes onto a moving surface;
transporting the volume of nanotubes continually deposited onto the moving surface away from a point of deposition;
removing the non-woven sheet from the moving surface; and
collecting the non-woven sheet from the moving surface.
15. A method as set forth in claim 14 , further including, prior to the step of depositing, generating an electrostatic field through which the nanotubes can be directed to permit substantial alignment of the nanotubes.