Mesoporous zirconium titanium oxides. Part 3. Synthesis and adsorption properties of unfunctionalized and phosphonate-functionalized hierarchical polyacrylonitrile-F-127-templated beads.

A method is presented for the preparation of zirconium titanate mixed oxides in bead form having hierarchical pore structure. This method entailed the use of both preformed polyacrylonitrile (PAN) polymer beads and surfactants as templates. The templates were removed by calcination at temperatures below about 500 degrees C, resulting in mixed oxide beads with trimodal pore size distributions and interconnected pores.

Mesoporous zirconium titanium oxides. Part 1: Porosity modulation and adsorption properties of xerogels.

A series of zirconium titanium oxide mesophases containing 33 atom % Zr have been prepared using carboxylic acids of different alkyl chain lengths (Cy ) from y=4-18 through organic-inorganic polymer phase segregation as the gel transition is approached. Thermal treatment of these transparent gels up to 450 degrees C eliminated the organic template, and domain coarsening occurred affording stable worm-hole mesoporous materials of homogeneous composition and pore diameters varying from about 3 to 4 nm in fine increments. With such materials, it was subsequently possible to precisely study the adsorption of vanadium oxo-anions and cations from aqueous solutions and, more particularly, probe the kinetics of intraparticle mass transport as a function of the associated pore dimension.

Mesoporous zirconium titanium oxides. Part 2: Synthesis, porosity, and adsorption properties of beads.

Mesoporous zirconium titanium mixed-oxide beads having disordered wormhole textures and mole fractions of Zr (x) ranging from x=0.25 to 0.67 have been prepared.

Delineating the first few seconds of supramolecular self-assembly of mesostructured titanium oxide thin films through time-resolved small angle X-ray scattering.

The early stages of evaporation induced self-assembly of titanium oxide mesophases from a precursor solution containing TiCl4 and the Pluronic triblock copolymer F-127 in HCl-water-ethanol solution have been studied using time-resolved SAXS techniques. Two experimental protocols were used to conduct these experiments. In one of these, the precursor solution was pumped around a closed loop as solvent was allowed to evaporate at a constant humidity-controlled rate.