Datum objave: 20.07.2011

Kategorija: Aktualno na Univerzi

Partnership request description:  SYNTHESIS OF SILICON NITRIDE, BORON NITRIDE and OTHER NANOTUBES FOR DIFFERENT PURPOSES Nanotubes are a new class of materials that are currently being studied intensively by many researchers. An increased interest to them has been generated by their unique characteristics. As we showed in [1,2] in 80th of the last century in the course of synthesis of sialons from kaolin (carbothermal reduction in nitrogen-containing medium) the sort of products strongly depends on the gas phase composition. When the process is performed in ammonia, the by-product of synthesis are silicon nitride fibers. As noted in [3], during the elementary silicon nitriding in the ammonia flow Si3N4 forms as fibers already at 1000 oC. The process proceeds through the intermediate stage where SixNyHz forms. Then, losing hydrogen, this compound trans forms into Si3N4. The performed experiments have demonstrated that silicon nitride nanotubes begin to form at the temperature above 1100oC. The considerable number of fibers form at 1100-1400 oC when the processes of the carbothermal SiO2 reduction and the product nitriding to Si2ON and further to Si3N4 begin in the initial charge. Considering the mentioned above information and results of morphological investigations, one can note the following points. Silicion nitride nanotubes begin to grow at temperatures above 1200 oC. At the temperature above 1400 oC the clear X-ray lines of nitride phases appear in diffractograms of the fibrous product. The halo corresponding to the nanotubes is absent. This suggests that at this temperature nanotubes transform into the fibers and have the clear crystalline structure. Using some technological methods, we have succeeded to produce the samples of nanotubes from pure ? or ß phases of Si3N4. When nanostructural carbon is used in the initial charge, the growth of fibers begins from the growth of nanotubes that gradually transform into fibers. Furthurmore, within the limits of this project it is expected to synthesize both the carbon tubes, boron nitride tubes and others. The application of nanotubes of three types in materials makes possible the improvement of mechanical, thermal and physico-chemical properties of materials of various purposes. References 1. P.P. Pikuza, I.?. Kiryakova, ?.S. Lugovskaya, D.V. S?hur, Khimicheskaya tekhnologiya, 1989, No. 1, P. 50-52 (in Russian). 2. V.?. Lavrenko, P.P. Pikuza, N.D. Rubtsova, D.V. S?hur, Khimicheskaya tekhnologiya, 1989, No. 5, P. 13-15 (in Russian). 3. T.S. Bortnitskaya, Pikuza P.P., Timofeeva I.I., Kosolapova ?.Ya., Neorganicheskie materialy, 1982, V. 18, No. 7, P. 1151-1153 (in Russian).
Project proposer:   Svetlana Zaginaichenko (Ukraine)
Description of the project offered:   Materials technology, Nanotechnology and Nanosciences, Renewable sources of energy, Energy storage. Energy. Transport, Energy saving, Hydrogen and fuel cell
Partner role:  Project participant
Partner organisation:  Research
Call for proposal title:  N/A

Description of the collaboration sought: We are interested in cooperation with organizations planed to submit an appropriate proposal
Expertise sought: Materials technology, Nanotechnology and Nanosciences, Renewable sources of energy, Energy storage. Energy. Transport, Energy saving, Hydrogen and fuel cells, Coordination. Cooperation, Scientific research,
Roles sought: Project coordinator, Project participant,
Organisation types sought:
Countries sought: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, United Kingdom, Albania, Bosnia-Herzegovina, Croatia, Iceland, Israel, Liechtenstein, Macedonia, Montenegro, Norway, Serbia, Switzerland, Turkey, Armenia, Azerbaijan, Brazil, Canada,