Controlling Size-Dispersion of Single Walled Carbon Nanotubes by Interaction with Polyoxometalates Armed with a Tryptophan Tweezer

A bis-tryptophan tweezer was installed on a polyoxometalate (POM) surface via a bis-amide covalent bond, yielding the enantiopure hybrid POM with C2 symmetry, as a result of the regioselective functionalization of decatungosilicate [?-SiW10O36]8- at the lacunary site. The combined polyanionic and receptor properties are instrumental for a POM-driven solubilization and enrichment of single walled carbon nanotubes (SWCNTs) with diameter <1.1 nm, as demonstrated by Raman and UV/Vis-NIR evidence, in agreement with the calculated energetics of the tryptophan tweezer-SWCNT interaction.