We present a comprehensive study of using diblock copolymer micelle templates to synthesize ordered nanoparticle arrays. Ionic and coordination bonds have been exploited to incorporate nanoparticle precursors into cores of block copolymer micelles. Polystyrene-b-poly (4-vinylpyridine) (PS-b-P4VP) has been shown to be able to localize anions via electrostatic attraction with protonated pyridine cations while transitional metals can be sequestered through coordination bonds. Polystyrene-b-poly (acrylic acid) (PS-PAA) can localize a variety of cations via ionic bonds with acrylic anions. We have demonstrated that the size of nanoparticles can be tuned by controlling the solution concentration of an ionic precursor. By mixing these two distinct block copolymers which can selectively interact with different precursor species, complex nanoparticle architectures can be generated thus paving a path for new applications.

TiO2 is a promising material for use in environmental purification due to its strong oxidizing power, photoinduced hydrophilicity, non-toxicity and long-term photostability. Nanocomposites formed by silver dispersed in titania matrix have their application quality improved since silver particles can act in the electronic structure of the titania. In this work, titanium isopropoxide and silver nitrate solution was used as starting of Ag/TiO2 nanocomposites. After irradiation and gelification at room temperature, this material was dried and calcined at various temperatures up to 1100 °C. The nanocomposites were characterized to investigate the structural evolution of the nanoparticles and the dependence of crystallite size with the calcination temperature.

By using tin chloride solution as the raw material, a nano-sized tin oxide powder with average particle size below 50 nm is generated by spray pyrolysis reaction. This study also examines the influences of the reaction parameters such as reaction temperature and the concentration of raw material solution on the powder properties. As the reaction temperature increases from 800 to 850 ℃, the average particle size of the generated powder increases from 20 nm to 30 nm. As the reaction temperature reaches 900 ℃, the droplets are composed of nano-particles with average size of 30 nm, while the average size of individual particles increases remarkably up to 80˜100 nm. When the tin concentration reaches 75 g/L, the average particle size of the powder is below 20 nm. When the tin concentration reaches 150 g/L, the droplets are composed of nano particles with average size around 30 nm, whereas the average size of independent particles increases up to 80˜100 nm. When the concentration reaches 400 g/L, the droplets are composed of nano-particles with average size of 30 nm.

This paper presents the development of a sensor to detect the oxidative and radiation induced degradation of polypropylene. Recently we have examined the use of crosslinked assemblies of nanoparticles as a chemiresistor-type sensor for the degradation products. We have developed a simple method that uses a siloxane matrix to fabricate a chemiresistor-type sensor that minimizes the swelling transduction mechanism while optimizing the change in dielectric response. These sensors were exposed with the use of a gas chromatography system to three previously identified polypropylene degradation products including 4-methyl-2-pentanone, acetone, and 2-pentanone. The limits of detection 210 ppb for 4-methy-2-pentanone, 575 ppb for 2-pentanone, and the LoD was unable to be determined for acetone due to incomplete separation from the carbon disulfide carrier.

Large-scale growth capability is a general requirement for any reliable and cost-effective device application. Catalyst-free vapor-phase growth techniques generally let obtain high purity materials, but their application in large-scale growths of zinc oxide (ZnO) nanostructures is not trivial, because the lack of catalysts makes the control of these process rather difficult. Three different optimizations of the basic vapor phase growth have been studied and performed to obtain selected and reproducible growths of three different ZnO nanostructures with improved yield, i.e. nanotetrapods, nanowires and nanorods. No precursor or catalyst has been used in order to reduce contamination sources as more as possible.