Glycolipid Nanotube Hollow Cylinders as Substrates: Fabrication of One-Dimensional Metallic-Organic Nanocomposites and Metal Nanowires

A synthetic glycolipid N-(11-cis-octadecennoyl)(beta)-D-glucopyranosylamine was employed for the fabrication of organic tubular structures with a cyclic hollow cylinder 30-50 nm wide through molecular self-assembly in water. Gold or silver nanoparticles encapsulated in the hollow cylinders of the lipid nanotubes (LNTs), GNPs@LNT or SNPs@LNT, respectively, were fabricated by loading aqueous gold (GNPs) or silver nanoparticles (SNPs) into the LNT hollow cylinders using capillary force. To explore an advanced fabrication method for one-dimensional organization of metals, we have removed the LNT organic shell of the GNPs@LNT or SNPs@LNT nanocomposite by firing the nanocomposite in air at 450-1000 C. A continuous gold nanowire 20-30 nm wide was successfully obtained under the firing conditions of T = 550-750 C, indicating that the inner cavity of the LNT can also be used as a template for the organization of gold nanowire. On the other hand, we have found no remarkable formation of silver nanowires after the same treatment for the SNPs@LNT nanocomposite as mentioned for the GNPs@LNT. All the nanostructures have been analyzed using transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray analysis (EDXA), and selected area electron diffraction (SAED).