Photodegrading hexaazapentacene dispersant for surface-clean semiconducting single-walled carbon nanotubes

To remove dispersant molecules on the surface of single-walled carbon nanotubes (SWCNTs) is one of main challenges for its practical application in electronics. In this paper, we demonstrated a photodegradable process as a promising method to remove off the dispersants from the surface of semiconducting SWCNTs (s-SWCNTs). A N-heterocyclic aromatic compound, 1,2,5,6-Tetra(5-octylthiophene-2-yl)-Hexaazapentacene (noted as 4HP-C8), was synthesized and used to enrich s-SWCNTs with high yield and purity. Importantly, 4HP-C8 was found to be sensitive to UV irradiation and therefore could be photodegraded into fragments, which provided a facile approach to harvest “dispersant-free” s-SWCNTs. The degradation process and reaction kinetics of 4HP-C8 were also carefully investigated.