Methods for selective functionalization and separation of carbon nanotubes
AssigneeWilliam Marsh Rice University
InventorsMichael S. Strano, Monica Usrey, Paul Barone, Christopher A. Dyke, James M. Tour, W. Carter Kittrell, Robert H Hauge, Richard E. Smalley
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Abstract
The present invention is directed toward methods of selectively functionalizing carbon nanotubes of a specific type or range of types, based on their electronic properties, using diazonium chemistry. The present invention is also directed toward methods of separating carbon nanotubes into populations of specific types or range(s) of types via selective functionalization and electrophoresis, and also to the novel compositions generated by such separations.
Claims30
A method for separating carbon nanotubes based on their electronic type, said method comprising:
- a) suspending a plurality of carbon nanotubes in a solvent to form a plurality of suspended carbon nanotubes;
- wherein the plurality of suspended carbon nanotubes comprise metallic carbon nanotubes, semimetallic carbon nanotubes and semiconducting carbon nanotubes;
- b) reacting a substoichiometric amount of a functionalizing species with the plurality of suspended carbon nanotubes such that the metallic carbon nanotubes and the semimetallic carbon nanotubes, but not the semiconducting carbon nanotubes, react with the functionalizing species to form a mixture comprising functionalized metallic carbon nanotubes, functionalized semimetallic carbon nanotubes and unfunctionalized semiconducting carbon nanotubes;
- wherein the substoichiometric amount of the functionalizing species is with respect to the amount of carbon comprising the carbon nanotubes;
- and
- wherein the substoichiometric amount of the functionalizing species is selected such that a reaction of the functionalizing species occurs with the metallic carbon nanotubes and the semimetallic carbon nanotubes but not with the semiconducting carbon nanotubes;
- and
- c) separating the functionalized metallic carbon nanotubes and the functionalized semimetallic carbon nanotubes from the unfunctionalized semiconducting carbon nanotubes.
A method for separating carbon nanotubes based on their electronic type, said method comprising:
- a) providing a plurality of functionalized carbon nanotubes suspended in a solution;
- wherein the plurality of functionalized carbon nanotubes comprise functionalized metallic carbon nanotubes, functionalized semimetallic carbon nanotubes, and unfunctionalized semiconducting carbon nanotubes;
- wherein the functionalized metallic carbon nanotubes and the functionalized semimetallic carbon nanotubes comprise phenolic OH moieties;
- b) raising the pH of the solution above 10 such that at least a portion of the phenolic OH moieties become deprotonated;
- and
- c) after raising the pH, separating the functionalized metallic carbon nanotubes and the functionalized semimetallic carbon nanotubes from the unfunctionalized semiconducting carbon nanotubes.
A method for separating carbon nanotubes based on their electronic type, said method comprising:
- a) suspending a plurality of carbon nanotubes in a surfactant solution to form a plurality of suspended carbon nanotubes;
- wherein the plurality of suspended carbon nanotubes comprise metallic carbon nanotubes, semimetallic carbon nanotubes and semiconducting carbon nanotubes;
- b) reacting a substoichiometric amount of a diazonium species with the plurality of suspended carbon nanotubes such that the metallic carbon nanotubes and the semimetallic carbon nanotubes, but not the semiconducting carbon nanotubes, react with the diazonium species to form a mixture comprising functionalized metallic carbon nanotubes, functionalized semimetallic carbon nanotubes and unfunctionalized semiconducting carbon nanotubes;
- wherein the substoichiometric amount of the diazonium species is with respect to the amount of carbon comprising the carbon nanotubes;
- and
- wherein the substoichiometric amount of the diazonium species is selected such that a reaction of the diazonium species occurs with the metallic carbon nanotubes and the semimetallic carbon nanotubes but not with the semiconducting carbon nanotubes;
- and
- c) separating the functionalized metallic carbon nanotubes and the functionalized semimetallic carbon nanotubes from the unfunctionalized semiconducting carbon nanotubes.
Dependencies are inferred from the claim text.