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Fullerene-like hollow nanoparticles
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| Transmission electron micrograph of a multi-walled WS2 nanoparticle (courtesy of R. Tenne). |
The prototypical hollow nanoparticle is the buckyball C60. However, fullerenes have been synthesized also with many different sizes and thicknesses (multi-walled fullerenes, also called carbon onions or Russian dolls), and more than 30 other materials which usually occur in layered form have been prepared as hollow nanoparticles in a similar way. One prominent example are inorganic fullerenes MeX2, with Me = W or Se and X = S or Se. In order to investigate the physical properties of hollow nanoparticles in general, we used continuum approaches to model their van der Waals interactions and elastic properties. The main objective of our work is to predict physical properties like phase behavior and mechanical stability as a function of particle size and shell thickness. A special objective of our work is to provide a useful theoretical background for the superior tribological properties of inorganic fullerenes, which have been demonstrated recently by the groups of Reshef Tenne (Weizmann Institute) and Jacob Israelachvili (Santa Barbara). Similar concepts can be easily applied to nanotubes. They also can be applied to colloidal core-shell particles with a hollow core, like hollow polyelectrolyte shells (e.g. biocapsules, experimental work at this institute by F. Caruso, E. Donath, H. Moehwald, A. Fery and G. Sukhorukov). Examples for similar structures in the biological domain are the actin cortex of animal cells (in particular of red blood cells) and clathrin coats (used by cells to stabilize budding vesicles).
Publications:
- U. S. Schwarz, S. A. Safran and S. Komura, Mechanical, adhesive and thermodynamic properties of hollow nanoparticles, Mat. Res. Soc. Symp. Proc. 651: T5.3.1-T5.3.6 (2001) (abstract, cond-mat/0201109, PDF)
- U. S. Schwarz and S. A. Safran, Phase behavior and material properties of hollow nanoparticles, Phys. Rev. E 62: 6957 - 6967 (2000) (abstract, cond-mat/0009027, PDF)
- U. S. Schwarz, S. Komura and S. A. Safran, Deformation and tribology of multi-walled hollow nanoparticles, Europhys. Lett. 50: 762-768 (2000) (abstract, cond-mat/0005017, PDF)
Last modified Tue Jan 8 17:18:50 CET 2002.
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