Mesostructured TiO2:: ligand-stabilized synthesis and characterization

The synthesis of mesostructured or even mesoporous metal oxides requires a certain interaction between the inorganic precursor and the organic structure-directing supramolecular template. In order to adapt the reactivity of a titanium alkoxide precursor for the synthesis of mesostructured TiO2, three different bidentate ligands -1,3-propanediol, 1,5-pentanediol and 2,4-pentanedione -were used. Due to their stabilizing properties, different mesostructured titania phases with structure periodicities in the order of 31.5 to 34 Angstrom could be synthesized. The resulting organic-inorganic composite structure did not show a sufficiently high degree of condensation between the TiO6 octahedra. X-ray absorption spectroscopic (XAS) studies revealed slightly larger bond lengths compared to the corresponding condensed phase anatase. All ways to remove the template lead to more condensed phases.