Nanostructured TiO2 based ceramics were synthesized using citrate-nitrate auto combustion method with different concentrations of aluminum oxide as dopant. The powder x-ray diffraction data showed that synthesized TiO2 powders, pure as well as alumina doped TiO2 had anatase phase. Dopant concentration was varied between 0 and 15 wt%. Particle size analysis showed that the particle size was in the range of 50 to 80nm for nanosized TiO2 calcined between 600 and 800°C. Average particle size of doped powders was generally less than pure TiO2. BET specific average surface area was between 10 and 25 m2/g. Doping upto 10wt% alumina is not effective in retarding anatase crystallite growth. The resistance of Al doped TiO2 sample is found to be lower than that of pure TiO2. Al2O3 doped TiO2 sensor was found to be selective to CO sensing at an operating temperature of 600 °C.

Nano-sized PtRu catalysts supported on carbon nanoparticles were synthesized by a polyol process. The PtRu catalyst prepared at pH=3 indicated higher catalysis for methanol oxidation than one prepared at pH=5.5. The samples were analyzed by techniques of the extended X-ray absorption fine structure (EXAFS), transmission electron microscope (TEM), X-ray diffraction (XRD) and X-ray fluorescence (XRF). Their results showed that the pH of the precursor solution during the polyol process affected the substructure of the PtRu nanoparticles. The correlation of the substructure with the catalytic activity was studied.

This work presents an innovative approach to produce monodisperse solution-phase triangular silver nanoparticles with well-controlled geometry. Ag nanotriangles are fabricated by nanosphere lithography (NSL), functionalized with alkanethiol molecules and then released from the substrate into solution. The resulting single isolated nanoparticles are subsequently asymmetrically functionalized with alkanedithiol molecules to form dimer pairs. The optical properties of the Ag nanoparticles have been measured using UV-Vis spectroscopy while their structural properties have been characterized using atomic force microscopy (AFM) and transmission electron microscopy (TEM). Theoretical calculations based on Mie theory and the Discrete Dipole Approximation (DDA) method have been done to interpret the optical properties of the released Ag nanoparticles.

Dilute aqueous solutions with Au3+ ions and Polyethylene Glycol Monostearate are irradiated with ∼1 MeV γ-ray from 60Co source, 10 MeV pulsed electrons or 1.6 GeV carbon ions. After the irradiation, the color of solutions changes from buff yellow to reddish color. The UV-vis absorption spectra show that after the irradiation, light absorption around 530 nm appears, which corresponds to the excitation of the surface plasmon due to Au nano-particles. The result confirms that the irradiation reduces Au3+ ions in the aqueous solutions and synthesizes Au nano-particles. Size and shape of the nano-particles are examined by using 200kV transmission electron microscope. Effects of irradiation parameters (total dose and dose rate) on Au nano-particle synthesis are discussed.

The microwave hydrothermal synthesis of silicalite zeolite was monitored in situ using small and wide angle X-ray scattering (SAXS and WAXS). A custom-built waveguide reactor provided the microwave heating at 2.45 GHz frequency. Microwave power up to 300 W was supplied by a SAIREM generator via a coax connection. A sample port in the waveguide section allowed a thin-walled glass sample vessel to be held in the microwave field. The sample vial was sealed with a fiber optic temperature probe used for monitoring the temperature. Silicalite zeolite precursor solutions were heated temperatures between 100 and 130°C for up to 120 minutes. The SAXS or WAXS patterns were simultaneously scanned during the reaction under microwaves via X-ray beam through slots in the side of the waveguide. The progress of silicalite zeolite formation was followed and the analysis of SAXS patterns showed the primary particles of 2 nm shifted to aggregates of 5.8 nm in diameter, in 120 minutes at 130°C.

A method for heating multiple types of magnetic nanoparticles independently is described. This technique exploits tuning of the size and material dependent properties of magnetic field heating of nanoparticles to allow independent heating by application of the field at different frequencies. Magnetic field heating experiments as a function of field frequency show that there is potential for this technique in vitro.

Nanoporous membranes based on anodized aluminum oxide are prepared with atomic level control of pore dimensions and pore wall compositions by atomic layer deposition and are under investigation for use in catalysis. Simulation and modeling help to understand reactivity in confined geometry and to develop rational design of these new materials. In this context, we present results of molecular dynamics simulations of amorphous aluminum oxide surfaces. The surface structure is discussed in terms of density profiles, bond angle distributions and coordination numbers of surface atoms.

We have established a process to fabricate Ag nanorod arrays with tunable morphology, hence tunable plasmonic properties. Based on a dynamic oblique deposition (DOD) technique, the nanorods are aligned in a way where their major axis is quasi-parallel. The aspect ratio of the nanorods is adjusted by choosing an appropriate DOD condition to show plasma resonance in the wavelength region around the Raman scattering at the excitation wavelength of 785 nm. The nanorod arrays thus tuned provide intense surface enhanced Raman scattering useful for practical applications to biochemical sensors.

The explicit expression for the linearized longitudinal quantum conductivity of inhomogeneous systems (such as semiconductor atomic clusters, artificial molecules, etc.) in weak electro-magnetic fields derived recently within a first principle quantum statistical mechanical approach in terms of the equilibrium two-time temperature Green functions (TTGFs) has been analyzed to develop analytical and computational means for its calculations. This has been done using a generalized continuous fraction method due to Zubarev and Tserkovnikov (ZT). The TTGFs have been related to Kubo's relaxation functions of the charge density and its gradients that can be computed using available quantum statistical mechanical algorithms and software. Thus, it becomes possible to predict the linearized quantum conductivity of any small system (in particular small semiconductor quantum dots (QDs)) as a function of external electromagnetic fields using a unified fundamental approach. This knowledge can be used to develop small semiconductor QD-based highly sensitive tunable sensors based on changes in the conductivity caused by external electromagnetic fields (in particular, radiation).

A quiet revolution is occurring in electronics where nanometals have the ability to revolutionize adhesives and solders, nano oxides are revolutionizing fuel cell efficiency, and nanowires as well as nanotubes have the potential both to enhance short term evolutionary and long term revolutionary improvement.

This paper outlines some roadmap predictions and picks three areas with concrete examples- nano metals for ink jet formation of circuits, nano oxides in fuel cells, and lithographically developed nanowires for sensor application and details technical and commercial progress.

Atomic scale computer simulations were used to investigate the surface stress induced deformation in nanoporous metals. A phase field model was used to generate digital nanoporous structures that are quantitatively similar to those created experimentally via dealloying. We analyze the important effects of surface relaxations on the macroscopic deformation in these samples as well as in small spherical clusters.

The Karlsruhe Microwave Plasma Process (KMPP), a versatile gas-phase process is applied to produce SnO2 and core shell SnO2/SiO2 nanoparticles which are, respectively, deposited in-situ on preheated Si-Substrates. These substrates are already equipped with an electrode microarray. The proof of sensor concept shows, that mechanically stable, nanoscaled and nanogranular gas sensing layers can be produced.

In a first step synthesis and deposition parameters of SnO2 are elaborated, and gas-sensitivity tests are performed. Additionally, annealing experiments are done. The morphology and struc-ture of nanoparticles is characterized by X-ray diffraction and TEM-methods. The layers are in-vestigated by SEM techniques and by XPS. The sensitivity of the nanogranular layer is deter-mined in comparison with a standard microarray equipped with sputtered layers. Particles crys-tallize in the tetragonal cassiterite structure. It is found that a precursor concentration of 3×10−6mol/l leads to particles with crystallite size in the region of 2nm, whereas a concentration of 5.5×10−4mol/l results in approximately 5nm particles. With the precursor concentration, columnar porous layers of 200nm thickness are obtained after a deposition time of 1min. This thickness is comparable to the one of sputtered layers. First sensor tests show 10 times higher sensitivity to isopropanol, compared to the standard array. The time of response is equivalent. The grain growth observed for bare and core/shell nanoparticles at 300°C is marginal.

A novel type of working electrode based on MWCNT is fabricated on silicon substrate for detection of total cholesterol. Multiwall carbon nanotubes (MWNT), which are vertically grown on a silicon platform, promote heterogeneous electron transfer between the enzyme and the working electrode. Immobilization of cholesterol oxidase (Pseudomonas fluorescens.) on the electrode is done by entrapment of the enzyme in a bio-friendly, water soluble polymer, polyvinyl alcohol (PVA), which also increases the hydrophilicity of the carbon nanotube (CNT) surface (with experimental evidence) and thereby facilitating the intimate attachment of the protein molecules. Cyclic voltammograms exhibit efficient detection of cholesterol in the range of 100-300 mg/dl, which covers the entire range of possible cholesterol concentration in human blood. The influence of interferents, like glucose, ascorbic acid and uric acid, present in the physiological fluids, is also examined. Owing to its compatibility with standard silicon microfabrication technology, the signal processing circuitry can also be integrated onto the same silicon substrate yielding a compact miniaturized biochip.

The understanding of the surface properties of metal nanoparticles is essential for exploiting their unique catalytic properties. This paper reports findings of the preparation of silica-supported Pt and Au nanoparticles and the FTIR characterization of CO adsorption on the supported nanoparticles. The nanoparticles were prepared by both a traditional impregnation method and molecular-capping based synthesis method. By comparing the spectroscopic characteristics of CO adsorption on these catalysts, similarities and differences in CO stretching bands have been identified. The findings are significant because important insights have been gained into the surface binding properties of Au and Pt nanoparticle catalysts.

Vanadium oxide nanostructures (V2O5 and VO2) were obtained by chemical vapor deposition of the alkoxide precursor [VO(OPri)3]. The nanomaterials were studied with respect to their morphological features (HR-SEM) and phase structure (XRD) followed by characterization as resisitive-type gas sensors. Given the high surface area, vanadium oxide (VOx) nanostructures show significant sensor response via resistance change upon reaction induced by carbon monoxide and desorption of adsorbed oxygen at 400 °C. Tin-doped VOx showed enhanced sensitivity of the films which suggests a higher number of active sensing sites or alternations in the intrinsic electrical properties of VOx by addition of SnO2 as dopant.

Au nanorod arrays were grown by electrodeposition in Au-backed nanoporous alumina templates modified with polyethylenimine (PEI) as an adhesion layer. By varying the concentration and molecular weight of PEI, the length of nanorod arrays could be finely controlled. The local length distribution was extremely narrow with relative standard deviations on the order of 2% for rod lengths from 700 nm to 17 microns. The uniform growth rate appears to be determined by the adsorbed PEI matrix, which controls the growth kinetics of the grains comprising the nanorods. Templates coated with poly(acrylic acid) did not impart fine control in nanorod growth. The nanorods could also be thermally annealed within the template and released as monodisperse particles of uniform size.