Ultrathin composite films: An indispensable resource for nanotechnology

Ultrathin nanocomposite films were prepared on solid supports via adsorption of organic and inorganic molecules from solution. Coordination geometry for transition metal ions was preserved by embedding metal ligands into titanium oxide gel films, and porous titanium oxide films were prepared by selective removal of organic components from polymer/metal oxide composite films using oxygen plasma processing. Nanoparticles coated with thin metal oxide films were employed to form hollow shell structures, and wrapping of molecules with thin metal oxide layers was successfully achieved by controlled reaction in solution. These new methodologies based on ultrathin composite films should be useful as fundamental tools for the preparation of nano-structured materials.