High-yield dispersions of large-diameter semiconducting single-walled carbon nanotubes with tunable narrow chirality distributions.

Here, we report a thorough study on the ability of fluorene-based semiconducting polymers to disperse large-diameter (average diameter ⟨d⟩ ≈ 1.3 nm) laser vaporization (LV) single-walled carbon nanotubes (SWCNTs). We demonstrate the ability to select purely semiconducting species using poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(6,6'-{2,2'-bipyridine})] (PFO-BPy) and poly[(9,9-dihexylfluorenyl-2,7-diyl)-co-(9,10-anthracene)] (PFH-A), producing samples with narrow and bright excitonic emission relative to comparable aqueous dispersions. Rapid processing and high yields offer the ability to easily incorporate these semiconducting SWCNTs into commercially scalable applications, as demonstrated by large-area thin films prepared by ultrasonic spraying. By modifying the growth temperature of the LV synthesis, we demonstrate the ability to tune the range of diameters and chiralities within dispersions by exerting synthetic control over the composition of the starting material. This synthetic control allows us to show that PFH-A preferentially disperses near-armchair semiconducting SWCNTs over a large range of diameters (0.8 nm < d < 1.4 nm) and induces unique solvatochromic shifts for the excitonic transitions of nanotubes with particular chiral indices.