Dragan Mihailovic

Equilibrium and non-equilibrium spectroscopy on Mo6S9-xIxnanowires

We studied the electron relaxation of MoSI nanowire thin films via femtosecond pump-probe spectroscopy. The obtained spectra show a combination of absorption bleaching and a structured excited state absorption. A relaxation behaviour involving three characteristic time scales is found and discussed in the framework of previously published band-structure calculations.

SYNTHESIS AND CHARACTERIZATION OF EPOXY-SINGLE-WALL CARBON NANOTUBE COMPOSITES

We present a study on the composite of 1 wt% single-wall carbon nanotubes (SWNTs) in epoxy resin. Composites were prepared by solution mixing of epoxy resin XY 444 (Vantico), polyamine hardener XV 279 (Vantico) and single-wall carbon nanotubes (SWNTs), as a thin film. We observed that addition of surfactant together with sonification were necessary in order to obtain more uniform composite. We used several techniques to investigate the nanocomposite material, such as scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The observed changes of the glass transition temperature (Tg) and electron micrographs indicate that the compatibility and interfacial adhesion between the nanotubes and epoxy resin are poor.

Mo 6 S 4.5 I 4.5 nanowires: dispersion studies and electron microscopy characterization of the bundles

The processing of most one-dimensional nano-materials such as carbon-nanotubes is hampered by the fact that they are insoluble. Here we show how a significant portion (≈12wt%) of the as-produced Mo6S4.5I4.5 nanowires is stably dispersed in isopropanol as small diameter nanowire bundles. Sedimentation studies, performed combining experiments and theory, show the presence of three phases in the raw material: impurity material, insoluble and soluble nanowire bundles. A purification procedure is also discussed. The three phases has been characterized by UV-Vix-IR spectroscopy and XPS showing their intrinsic diversity.

Conducting Properties of Single Bundles of Mo6S3I6 Nanowires

The implementation of Mo6S3I6 nanowires (MoSI) in microelectronics requires basic evaluation of their electronic properties. Low‐ohmic contacts between the bundles and metallic guides is crucial. We describe resistivity measurements for bulk samples and for single bundles of MoSI nanowires. In the first case (Moly‐paper), variable range hopping consistent with electrons traveling through the mesh of bundles was observed. Using e‐beam lithography a device for longitudinal measurement of conductivity of single bundles was manufactured. A dependence on the different contact configurations is reported.