Nanohybrid shish-kebab supramolecular structure of single-walled carbon nanotubes/N,N′-dioctyl perylene tetracarboxylic diimide

Abstract

In the present work, carbon nanotubes (CNTs)-induced solution crystallization of N, N′-dioctyl perylene tetracarboxylic diimide (PTCDI-C8) in o-dichlorobenzene was studied. It is found that the nanohybrid shish-kebab (NHSK) supramolecular structure, wherein the single-walled carbon nanotubes (SWCNTs) serve as the shish and PTCDI-C8 crystals are the kebabs, with regular arrangement of the kebabs can be formed. UV–vis, photoluminescence spectroscopy and XPS studies reveal that there exist strong π-π interaction between PTCDI-C8 and SWCNTs, and some PTCDI-C8 molecules are already adsorbed on SWCNTs surface prior to crystallization. This is the first example of NHSK structure formed by CNTs and organic small molecules. Nevertheless, multi-walled carbon nanotubes (MWCNTs) cannot induce PTCDI-C8 to form NHSK structure under the same conditions. This indicates that geometric confinement may be the predominant factor affecting the orientation of the pre-adsorbed PTCDI-C8 molecules and epitaxial growth of the crystals.