Enhanced solubilization of large-diameter single-walled carbon nanotubes with amino-functionalized dipyrene nanotweezers

Pyrene-based nanotweezers 1 consisting of two pyrenes and amino-substituted carbazole in between have been successfully synthesized via Suzuki–Miyaura coupling reaction. The supramolecular complex formation of nanotweezers 1 with single-walled carbon nanotubes (SWNTs) was studied, and it was found that nanotweezers 1 exhibited much higher the SWNTs extraction ability as compared to the analogous dipyrene nanotweezers 2 and 3 with soluble alkyl-substituents. This enhanced extraction ability of 1 can be attributed to the formation of more stable SWNT complexes in methanol. On the basis of photoluminescence excitation and UV–Vis-NIR absorption of 76-CoMoCAT SWNTs before and after the extraction, nanotweezers 1 were found to show high selectivity towards (8,4)-, (7,6)-, (9,4)-, and (8,6)-SWNTs with diameter ranging from 0.84 to 0.97 nm.