Synthesis of Porous Nanocrystalline TiO2 Foam

Abstract

Direct decomposition and reaction of hydrogen peroxide inside a titanium dioxide/hexadecylamine slurry dispersion results in a foaming, inorganic/organic hybrid composite material containing TiO2 with intercalated hexadecylamine with extended, sponge-like, porous structure. The complex structure of the synthesized foams can be described by a self-assembly of the amine moieties between the TiO2 nanoparticles. The surfactant molecules, held together by hydrophobic interactions between the alkyl chains, are intercalated inside thin planar TiO2 walls in a way that a lamellar nanostructure is formed. The XRD basal distance of 46.8 Å is consistent with a crystal unit containing two surfactant molecules with alkyl chains perpendicular to the titanium dioxide walls. The hydrophilic amine headgroups are oriented with strong affinity to the hydroxyl groups present on the oxide surface.