From Self-Assembled Microspheres to Self-Templated Nanotubes: Morphologies and Properties of Sulfur-Bridged Fluoranthene-Based Organic Materials

The inability to controllably synthesize organic nanomaterials with desired morphologies and properties is a major barrier that prevents the scientific development of organic nanomaterials. A controllable method by means of adjusting the solubility of organic reactant has now been applied to Construct sulfur-bridged fluoranthene-based materials with desired spherical or tubular morphologies, based on the Williamson type of reaction starting from perchlorinated fluoranthene and disodium salt of 2,5-dimercapto-1,3,4-thiadizaole. A disubstituted fluoranthene derivative is proved as the basic building block for the organic materials by the data of mass spectrometry, X-ray photoelectron spectroscopy, as well as crystallography. Through quenching the intermediates toward the fluoranthene-based microspheres or nanotubes, the routes of self-assembly via a vesicle pathway and self-template from perchlorinated fluoranthene rods are proposed for the growth of the microspheres and the nanotubes, respectively. The proposed routes can be extended for synthesis of other aromatic molecular materials with controllable morphologies. On the basis of the reaction with thiol groups retained on the surface of the as-synthesized materials, functional groups or noble metal nanoparticles have been facilely linked to the fluoranthene-based materials for potential applications. Morphology-dependent properties of the fluoranthene-based materials have been demonstrated, on the basis of the experimental evidence about strong near-infrared absorption exhibiting in the microspheres but lacking in the nanotubes.