Formation of cobalt oxide nanotubes: Effect of intermolecular hydrogen bonding between Co(III) complex precursors incorporated onto colloidal templates

Several water-soluble cobalt(Ill) complexes were employed as precursors to form cobalt oxide nanostructures. These complexes were incorporated into polyelectrolyte multilayers precoated onto colloidal particles, followed by calcination. Cobalt complexes with strong intermolecular hydrogen bonding form one-dimensional Co3O4 nanotube structures. Short Co3O4 nanotubes with defects and broken spheres are formed when cobalt complexes with weak or no intermolecular hydrogen bonding are used. The sites for disulfide bond formation present on some complexes were found to be unessential for the nanotube formation.