US Patent 8057686 - Molecular tag for nanotube separation

http://www.freepatentsonline.com/8057686.html

This patent from Micron Technology teaches a method of removing defective carbon nanotubes based on molecular tags which are chemisorbed on defective portions of the nanotubes.

1. A defective nanotube separation method comprising:

depositing by atomic layer deposition a tag on a nanotube having a conductive, semiconductive, or insulative type of intrinsic conductivity in a nanotube mixture, the nanotube having a defect, the tag depositing at the defect where a deposition rate is greater than on another nanotube in the mixture lacking the defect, the other nanotube having the same type of intrinsic conductivity as the tagged nanotube, and the tag not depositing on the other nanotube;

removing the tagged nanotube from the mixture by using the tag; and

after the removing, the mixture containing the untagged other nanotube having the same type of intrinsic conductivity as the tagged nanotube.