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A one-pot, soft-chemistry, surfactant-assisted co-assembly approach to prepare La(sub 1-x)Sr(sub x)MnO3 (LSM)/Y2O3-stablilized ZrO2(YSZ) nanocomposites for use as solid oxide fuel cell (SOFC) cathods is investigated. Careful control of the stoichiometry of the LSM reagents in the aqueous synthesis determining the phase purity of the LSM perovskite and doping level of strontium.

The first synthesis of microspheres comprised of polyferrocenylsilane, a metallpolymer, by a precipitation polymerization methodology, is reported. Upon oxidation, PFSMSs undergo electrostatic self-assembly with silica spheres to form core-shell composite particles.

Redox-based hydrothermal synthetic methodologies have enabled the preparation of a new series of stoichiometrically pure jarosities of the formula, AV3(OH)6(SO4)2 with A=Na(super +1) K(super +1), RG(super +1), TI(super +1), and NH4(super +1). The vanadium jarosites display strong ferromagnetic interactions that are unprecedented in Kagome layers.

Three new redox-based, hydrothermal, synthetic methods are developed for the preparation of a new series of jarosites, in high purity and in single crystalline form. A comparative study of the new synthetic models reveals widely divergent magnetic properties, thus pointing to the importance of the new redox synthetic methods to future magnetism studies of jarosite compounds.

The evolution of a ceramic from a ceramic from a metal containing polymer, in which the variation of pyrolysis conditions facilitates control of ceramic structure and composition, influencing magnetic and mechanical properties is described. The pyrolysis of cross-linked polyferrocenylsilane 4 gave shaped macroscopic magnetic ceramics in which alpha-Fe nano-particles are encapsulated in a SiC/C/Si3N4 matrix.

A new form of mesoporous yttria-zirconia materials suitable as electrode materials in solid oxide fuel cells, have been synthesized.

It has been possible to identify a periodic mesoporous organosilica containing bridge-bonded ethene groups directly integrated into the silica framework. The surfactant templates were solvent-extracted and ion-exchanged to form a stable and periodic mesoporous ethenesilica with high surface area and ethene groups that are easily accessible for chemical reaction. The periodic mesoporous organosilicas, containing organic groups inside the walls of mesoporous silica, were compared with mesoporous silica containing tethered vinyl groups inside the channels.

Microporous materials have extensive use as catalysts, sorbents and ion-exchange media. There are reports of various oxide-based mesoporous materials, and the challenge is to expand their scope beyond the oxides. CdS, SnS(sub2) and CdSe are the only non-oxide mesostructured composites reported. A new group of metal germanium sulphide mesostructured materials are reported, prepared by an assembly of adamantanoid cluster precursors. Such materials could have applications in detoxification of heavy metals in polluted water steams, sensors and semiconductor quantum anti-dot devices.

Scanning electron microscopy, transmission electron microscopy and polarized optical microscopy were utilized to index the basic configurations and surface patterns, to confirm connections between morphology and structure, and to establish the relationship between optical anisotropy and the periodic porous mesostructure, respectively. Optical anisotropy arise from the global polarization of an average electron density. Furthermore, the geometries governing the structures reveal an underlying growth and curvature pattern characteristic of a nonequilibrium system and are dependent on the choice of the reaction parameters.

Oriented and free-standing thin mesoporous silica films are produced by the deposition of silica-surfactant micellar molecules on a surfactant overstructure at the air-water interface. The silicates polymerize and interact with the surfactant overstructure and micellar aggregates. Channels in the films are hexagonal and are oriented parallel to the water-air interface. The root-mean-square surface roughness is 3 angstroms for the continuous films. They are resistant to bending but can be transferred to substrates of various shapes.

The synthesis of crystalline mesolamellar aluminophosphates (MLA) involves the templating by self-agglomerated organic aggregates in non-aqueous tetraethylene glycol, phosphoric acid and amphiphilic alkylamine. X-ray diffraction analysis of the structure of MLA reveals that the morphology and surface patterns depend upon two distinct decylammonium dihydrogen phosphate assemblies. The skeletal characteristics of MLA such as deficiency of long-range order and bowl-like characteristics are found to be similar to radiolarians and diatoms.

Selenophene-thiophene block copolymers are prepared. The studies have confirmed that the domains are either rich in selenophene or thiophene, displaying that the blocks of distinct heterocycles has associated with one another in the solid state, and they have also shown a phase separation that is controlled by elemental differences.

The solution-phase formation of ordered lamellar nanocrystal (NC) arrays is described, where the semiconductor lamellae has displayed structural integrity and temporal stability, without recourse to chemical cross-linking. The encapsulation of gold nanoparticles has caused photoluminescence enhancement of the host CdSe nanocrystals.

The self-assembly of diblock copolymers within the nanoscale periodic voids of colloidal crystal (CC) templates, that can be obtained from the self-assembly of ceramic or polymeric microspheres and can generate inverse CCs through a templating approach, is investigated. The periodic voids present a large surface-to-volume ratio and are expected to strongly influence the self-assembly of block copolymers through interfacial interactions.

The synthesis of shell-cross-linked organometallic nanotubes of silver that contain a polyferrocenylsilane (PFS) inner wall covered by a cross-linked network of polymethylvinylsiloxane chains is reported. The result showed that pretreatment of PFS with organic oxidants such as dichloromethane is the key step to obtain silver particles within the tubes in high yields and the resulting soluble peapod-like hybrid nanostructures may ultimately be useful for the fabrication of nanodevices.

The new path to periodic mesoporous aminosilicas (PMAs) containing amine functional groups in the framework of a mesoporous network is discussed. High stability upon storage was observed in PMAs obtained form periodic mesoporous organosilicas (PMOs).

A new approach is described for production of hybrid periodically structured nanocomposites containing semiconductor or metal NPs. Using this approach, nanocomposite materials with periodically modulated magnetic and electric properties can be produced by incorporating metal NPs in three-layer microbeads.