Národní úložiště šedé literatury Nalezeno 3 záznamů.  Hledání trvalo 0.01 vteřin. 
Study of mechanical properites of nanostructured polymer coatings prepared using plasma enhanced chemical vapor deposition
Buršíková, V. ; Homola, V. ; Peřina, Vratislav
The aim of the present work was to deposit transparent polymer SiOxCyHz protective coatings from hexamethyldisiloxane/ oxygen mixtures in capacitively coupled glow discharge. The coatings prepared under dusty plasma conditions showed nanocomposite character. Complex characterization of the local mechanical properties was carried out on the prepared samples from nano to microscale using indentation techniques. The coatings were very elastic, they exhibited high elastic recovery and low plastic deformation even at indentation depths approaching the coating thickness.
Influence of H2O2 treatment on morphological and photoluminescence properties of hydrothermally grown ZnO nanorods
Yatskiv, Roman ; Grym, Jan
We report photoluminescence properties of hydrothermally grown ZnO nanorods (NRs) before and after hydrogen peroxide (H2O2) treatment. The H2O2 treatment introduces oxygen related defects and thus enhances chemisorption processes in ZnO NRs. These effects amplify interactions between the gas species and adsorbed oxygen and thus can influence sensing properties of ZnO NRs
Monolayers of platinum nanoparticles prepared by dip-coating
Černohorský, Ondřej ; Grym, Jan ; Yatskiv, Roman ; Pham, V.H. ; Hudry, D. ; Dickerson, J.H.
Platinum is a transition metal known for its catalytic properties, which are further enhanced when employed in a nanoparticle form. We have recently shown that a monolayer of Pt nanoparticles deposited on semiconductor substrates forms high quality Schottky diodes, which were used in sensitive hydrogen sensors with a detection limit of 1 ppm of H-2 in N-2. Preparation of ordered monolayers of Pt nanoparticles is essential for the understanding of the behaviour of such an interface. To obtain a hexagonal closed-packed nanoparticle array, we prepared Pt nanoparticles stabilized by oleylamine and oleic acid with a narrow size distribution and uniform shapes. A monolayer prepared by dip-coating of Si substrate in the suspension containing Pt nanoparticles showed hexagonal arrangement within separate domains with the surface coverage up to 90%. The increase of the surface coverage with increasing withdrawal speed of the dip-coating process was observed