Methods and compositions for the separation of single-walled carbon nanotubes
View Patent ↗Embodiments herein describe a composition including at least one water-soluble complex having a water-soluble separation agent including a planar portion, at least one pi electron on the planar portion and at least one electron withdrawing group; and a semiconducting single-walled carbon nanotube in an aqueous solution. Further embodiments describe a method of separating metallic single-walled carbon nanotubes and semiconducting single-walled carbon nanotubes including providing carbon nanotubes having an admixture of semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes; and combining the admixture with a water-soluble separation agent in an aqueous solution to form a mixture, in which the water-soluble separation agent includes a planar portion, at least one pi electron on the planar portion and at least one electron withdrawing group.
1. A method of separating single-walled carbon nanotubes, the method comprising:
providing carbon nanotubes comprising an admixture of semiconducting single-walled carbon nanotubes and metallic single-walled carbon nanotubes; and
combining the admixture with a water-soluble separation agent in an aqueous solution to form a mixture,
wherein the separation agent selectively associates with the semiconducting single-walled carbon nanotubes in the admixture to form a water-soluble complex,
wherein the water-soluble separation agent comprises a planar portion, at least one π electron on the planar portion and at least one electron withdrawing group.
2. The method of claim 1 , wherein the water-soluble separation agent is a poly-aromatic hydrocarbon substituted with the at least one electron withdrawing group, or a salt thereof.
3. The method of claim 2 , wherein the poly-aromatic hydrocarbon is selected from the group consisting of coronene, perylene, pyrene, fluoranthene, anthracene, acenaphthylene, acenaphthene, chrysene, phenanthrene, naphthalene, corannulene, triphenylene, ovalene, tetracene, pentacene, a salt thereof, an analog thereof, a derivative thereof and a combination thereof.
4. The method of claim 2 , wherein the poly-aromatic hydrocarbon is a poly-aromatic hydrocarbon salt selected from the group consisting of potassium, sodium, lithium, or a combination thereof.
5. The method of claim 1 , wherein the electron withdrawing group is selected from the group consisting of —COO − , —SO 3 − , —NH (3-n) R n + , and a combination thereof,
wherein each R is independently H, or C 1 to C 6 alkyl; and
n is 1, 2 or 3.
6. The method of claim 1 , wherein the separation agent comprises coronene or a salt thereof.
7. The method of claim 1 , wherein the separation agent comprises a potassium salt of coronene-1,2,7,8-tetracarboxylic acid.
8. The method of claim 1 , further comprising reversing the association between the separation agent and the semiconducting single-walled carbon nanotubes to form dissociated semiconducting single-walled carbon nanotubes.
9. The method of claim 8 , wherein the reversing the association step comprises adding sufficient water to the aqueous solution to weaken the association between the semiconducting single-walled carbon nanotubes and the separation agent.
10. The method of claim 1 , further comprising precipitating the metallic single-walled carbon nanotubes from the aqueous solution to form a precipitate.
11. The method of claim 8 , wherein the reversing the association step comprises evaporating water from the aqueous solution and washing the complex with water to disassociate the semiconducting single-walled carbon nanotubes from the separation agent.