Toward the extraction of single species of single-walled carbon nanotubes using fluorene-based polymers

Abstract

High purity of (7,5) SWNTs (∼79% of the semisonducting SWNT ensemble) can be obtained by polymer-assisted extraction from the narrow-diameter distributed SWNTs produced by the catalyst Co-MCM-41. The fluorene-based polymers are able to selectively wrap the single-walled carbon nanotubes (SWNTs) with certain chiral angles or diameters depending on their chemical structures. Poly(9,9-dioctyfluoreny1-2,7-diyl) and poly[(9,9-dihexylfluorenyl-2,7-diyl)-co- (9,10-anthracene)] selectively wrap SWNTs with high chiral angles (>24.5°). By contrast, poly[9,9-dioctylfluorenyl-2,7-diyl)-co-1,4-benzo- {2,1′-3}-thiadiazole)] preferentially wraps the SWNTs with certain diameter (1.02-1.06 nm). © 2007 American Chemical Society.