Perylene-based nanotweezers: enrichment of larger-diameter single-walled carbon nanotubes

The solubilization of single-walled carbon nanotubes (SWCNTs) by a novel tweezer-shaped molecule with perylene bisimide moieties that act as aromatic anchoring groups is presented. Encouraging results of the tweezer-dispersion concept is combined with the outstanding exfoliation and dispersion efficiencies of designed perylene bisimide derivatives, which have previously turned out as most-powerful SWCNT dispersants. Based on the preferred interaction between the nanotweezer and SWCNTs with diameters larger than 0.8 nm, the supernatant was depleted after mild centrifugation in SWCNT species of smaller diameters. Characterization was carried out by a combination of UV/Vis and nIR absorption spectroscopy as well as emission spectroscopy of the SWCNTs and perylene. This study presents the foundation for a further improvement of selective SWCNT dispersion and sorting by designed molecules.