| Nanocrystal |
| Written by Henk van Esch |
| Friday, 06 February 2009 11:39 |
“Science” Reveals: For the First Time, Researchers from the Technion and the University of Bayreuth in Germany Succeed in Producing and Characterizing Platinum Crystalline Nanoparticles of 2 to 3 Nanometers in DiameterIn the future, the discovery will enable preparation of more efficient catalysts and will save energy and production costs in industry; the German researcher spent four months at the Technion for this researchResearchers from the Technion and the University of Bayreuth in Germany have succeeded, for the first time, in producing and characterizing platinum crystalline nanoparticles of 2 to 3 nanometers in diameter. This was published in the latest edition of the prestigious scientific journal “Science”. In the article, the researchers describe the preparation of crystalline nanoparticles of 2 to 3 nanometers in diameter. Each particle is a single platinum crystal. Such particles have increased catalytic ability (the ability to speed up chemical reactions). The particles were formed by the research partners – Prof. Matthias Ballauff and his doctoral student Marc Schrinner from the University of Bayreuth in Germany. Their detailed characterization was carried out by Prof. Yeshayahu Talmon of the Technion’s Faculty of Chemical Engineering and Dr. Yaron Kauffmann of the Technion’s Faculty of Materials Engineering in the Technion’s advanced electron microscopy laboratories. The particles were formed and immobilized on polymer “brushes” affixed to polystyrene particles (a type of polymer). In the first stage, nanoparticles of a gold-platinum alloy were prepared, and then the gold was dissolved by cyanide ions – leaving behind platinum nanocrystals. The polymer particles carrying the metal nanoparticles were imaged in the aqueous suspension at low temperatures by cryogenic-temperature transmission electron microscopy (cryo-TEM). The metal nanoparticles were analyzed by atomic-resolution transmission electron microscopy, showing the arrangement of individual gold atoms in the nanocrystals. This combination of electron microscopy laboratories is unique to the Technion. Without the sophisticated equipment, the expertise and experience of the Technion scientists, this characterization work would have not been possible. Dr. Schrinner spent four months at the Technion to perform the characterization work. His visit was supported by the Technion Russell Berrie Nanotechnology Institute and the Minerva Foundation. It should be noted that the composite systems of the core particles and the platinum single nanocrystals exhibit excellent stability, as well as high catalytic activity in hydrogenation reactions (the addition of hydrogen to the molecule) in the aqueous phase. In the future, the discovery will enable preparation of more efficient catalysts and will save energy and production costs in industry. Photo: Atomic-resolution transmission electron microscopy picture that shows individual platinum atoms (the dark spots) inside the nanocrystal. Photo by Dr. Yaron Kauffmann using the “Titan” microscope at the Technion.  Technion Spokesman, Amos Levav: 052-4524873 |
| Last Updated on Friday, 06 February 2009 11:45 |