Systems and methods related to the formation of carbon-based nanostructures

1. A method of growing carbon nanotubes, comprising:

exposing a carbon nanotube precursor comprising a solid to a nanopositor comprising a zirconium oxide under conditions causing the formation of carbon nanotubes on the nanopositor.

2. The method of claim 1 , wherein fewer than about 2% of the zirconium atoms in the zirconium oxide are reduced to a zero oxidation state during the formation of the carbon nanotubes.

3. The method of claim 1 , wherein fewer than about 2% of the zirconium atoms in the zirconium oxide form a zirconium carbide during the formation of the carbon nanotubes.

4. The method of claim 1 , wherein the zirconium oxide has an oxygen to zirconium ratio ranging from about 1.0 to about 2.0.

5. The method of claim 1 , wherein the nanopositor is in contact with a growth substrate.

6. A method of growing carbon nanotubes, comprising:

exposing a carbon nanotube precursor to a nanopositor comprising a zirconium oxide under conditions causing the formation of carbon nanotubes on the nanopositor, wherein the nanopositor is in contact with a growth substrate comprising at least one of amorphous carbon, carbon aerogel, carbon fiber, graphite, glassy carbon, carbon-carbon composite, graphene, aggregated diamond nanorods, nanodiamond, or diamond.

7. The method of claim 6 , wherein the precursor material comprises at least one of a hydrocarbon and an alcohol.

8. The method of claim 1 , wherein the set of conditions comprises a pressure substantially equal to or less than about 1 atmosphere.

9. The method of claim 1 , wherein the set of conditions comprises a temperature between about 300-1100° C.

10. The method of claim 1 , wherein the nanopositor comprises a dopant.

11. The method of claim 10 , wherein the dopant comprises at least one of Ca, Mg, Sr, Ba, Y, and Mo.

12. The method of claim 10 , wherein the nanopositor comprises between about 0.1 atomic % and about 5 atomic % calcium.

13. The method of claim 1 , wherein the solid comprises at least one of coal, coke, amorphous carbon, unpyrolyzed organic polymers, partially pyrolyzed organic polymers, diamond, graphene, and graphite.

14. A method of growing carbon nanotubes, comprising:

exposing a carbon nanotube precursor to a nanopositor comprising at least one of metal atoms in a non-zero oxidation state and metalloid atoms in a non-zero oxidation state under conditions causing the formation of carbon nanotubes on the nanopositor, wherein:

the nanopositor comprises a dopant;

formation of the carbon nanotubes occurs in the absence of a growth substrate in contact with the nanopositor,

the nanopositor is suspended in a fluid during the formation of the carbon nanotubes,

fewer than about 2% of the at least one of metal atoms in a non-zero oxidation state and metalloid atoms in a non-zero oxidation state are reduced to a zero oxidation state during the formation of the carbon nanotubes, and

fewer than about 2% of the at least one of metal atoms in a non-zero oxidation state and metalloid atoms in a non-zero oxidation state form a carbide during the formation of the carbon nanotubes.

15. The method of claim 1 , wherein substantially none of the zirconium atoms in the zirconium oxide are reduced to a zero oxidation state during the formation of the carbon nanotubes.

16. The method of claim 1 , wherein substantially none of the zirconium atoms in the zirconium oxide form a zirconium carbide during the formation of the carbon nanotubes.

17. The method of claim 1 , wherein the solid comprises at least about 25 wt % carbon.

18. The method of claim 1 , wherein the solid comprises at least about 90 wt % carbon.

19. The method of claim 6 , wherein the zirconium oxide has an oxygen to zirconium ratio ranging from about 1.0 to about 2.0.

20. The method of claim 6 , wherein the precursor material comprises at least one of a hydrocarbon and an alcohol.

21. The method of claim 6 , wherein the nanopositor comprises a dopant.

22. The method of claim 6 , wherein the carbon nanotube precursor comprises a solid.

23. The method of claim 14 , wherein substantially none of the at least one of metal atoms in a non-zero oxidation state and metalloid atoms in a non-zero oxidation state are reduced to a zero oxidation state during the formation of the carbon nanotubes.

24. The method of claim 14 , wherein substantially none of the at least one of metal atoms in a non-zero oxidation state and metalloid atoms in a non-zero oxidation state form a carbide during the formation of the carbon nanotubes.

25. The method of claim 14 , wherein the dopant comprises at least one of Ca, Mg, Sr, Ba, Y, and Mo.

26. The method of claim 14 , wherein the carbon nanotube precursor comprises a solid.

27. The method of claim 26 , wherein the solid comprises at least one of coal, coke, amorphous carbon, unpyrolyzed organic polymers, partially pyrolyzed organic polymers, diamond, graphite.

28. The method of claim 14 , wherein the nanopositor comprises a metal oxide.

29. The method of claim 28 , wherein the nanopositor comprises at least one of a zirconium oxide, a silicon oxide, an aluminum oxide, a titanium oxide, an yttrium oxide, a hafnium oxide, a tantalum oxide, a niobium oxide, and a molybdenum oxide.

30. The method of claim 28 , wherein the nanopositor comprises a zirconium oxide.

31. The method of claim 14 , wherein the nanopositor comprises a metalloid oxide.

32. The method of claim 31 , wherein the nanopositor comprises at least one of a silicon oxide and a germanium oxide.