New methods for fabrication of amorphous nanostructures of pure metals
|Event Date:||January 30, 2013|
|Speaker:||Dr. Vladimir Kozhevin
Senior Research Scientist
Ioffe Institute, Russia
Technical application of amorphous metals is restricted mainly by two factors. First, only materials having low rate of crystal growth can be transited into amorphous state by existing methods. Second, amorphous materials are unstable due to their crystallizing at relatively low temperature. To solve these problems, one should find a way to break up melted metal up to nanometer size droplets before solidification of this melt. To produce metal nanodroplets we use method of laser ablation of metal target. It was found mode of this method operation when processes of plasma heating and expansion are consistent with the processes of formation and fission of metal droplets ejected from metal target. Experiments show that thin films of all metals produced by this method are amorphous and unusually stable against coagulation and oxidation. Due to these effects the nanostructured films fabricated by developed method have unique structural, electrical magnetic and catalytic features.
Dr. Kozhevin graduated in 1972 from the Mathematical and Mechanical Department of Leningrad State University. During the same year Dr. Kozhevin was employed in Efremov Institute of Electrophysical Apparatus at St. Petersburg, Russia. In this Institute Dr. Kozhevin studied processes of plasma heating in different conditions. These studies where related both to fusion and to various technological applications. In 1983 Dr. Kozhevin defended his candidate's (Ph.D.) thesis “Plasma dynamics in ultrafast theta-pinches”.
Since 1995 Dr. Kozhevin has been working at the Physical-Technical Institute RAS where his activity is mainly focused on the development of novel nanotechniques and on the studying of the features of structures fabricated by these techniques. Particularly, a new laser electrodispersion technique designed for fabrication of metal nanostructures is based on results of his theoretical studies. Nanostructures fabricated by this method have unique features which are usable for different applications. Currently Dr. Kozhevin is concentrating on the elaboration of a new technique of metal droplets dispersion, which is developed for highly efficient fabrication of metal nanostructures. Both techniques are patented in RF, USA, EU, Canada, and China.
Dr. Kozhevin has more than 80 scientific publications and 9 patens.
2013-01-30 15:30:00 2013-01-30 16:30:00 America/New_York New methods for fabrication of amorphous nanostructures of pure metals EE 170