New: International conference Nanax3 to be held in Lecce May 2008
Self assembly of nanoparticles is one of the hot topics of current research that offers great potential for innovation in the biomedical, energy and communication sectors
Colloidal nanocrystals emit light of different color depending
on their size and shape. Each of the displayed vials contains several
billions of identical nanoparticles.
Self assembly is one of the basic concepts of life and matter. We admire
it in the beauty of diamonds, observe it in the line-up of birds on long
distance flights, and see it in our children as they grow up based on
the information stored in DNA molecules. So why not apply it for technology?
Wouldn’t it be wonderful if we just need to pour the ingredients for a
specific device into a beaker, and the atoms and molecules move to the
right place like by magic? Take the electronic and communication industry:
controlled self assembly of functional nanoparticles into the device structures
would not need costly fabrication lines. It would significantly reduce
the impact of the production on our environment. Self assembly of colloidal
nanocrystals will stimulate innovation in a large variety of industrial
sectors. The European Comission financed SA-NANO (Self Assembly of Shape
Controlled Colloidal Nanocrystals) project aims at understanding of the
basic principles of self assembly of shape controlled colloidal nanocrystals
in order to develop approaches to control these self-stimulated ordering
processes into tailored functional structures. SA-NANO consists of an
interdisciplinary consortium of experts in the fields of nanochemistry,
physics, biofunctionalization, and computational modeling originating
from six different countries.
Targeted application areas:
In optical devices, light emitting diodes based on nanosize semiconductor nanocrystals are foreseen to have much less power consumption than ordinary light bulbs. Towards innovative LED screens we can imagine that nanocrystals in combination with plastics could lead to flexible foils that can be folded or rolled up like a newspaper. An even more elaborate application of such new media can evolve into an electronic paper-like display. Additional applications will be in the area of wavelength-selectable optical devices. Potentially, nanocrystal based lasers can be tuned to arbitrary wavelengths from the ultraviolet to the infrared. In particular, the ability to fabricate shape-controlled nanocrystals in the important near-infrared telecommunications wavelengths makes them interesting for expanding the bandwidth needs of the telecommunications industry.
In the biomedical sector, multifunctional nanocrystal assemblies could open new fields in the diagnosis and cure of diseases. We can imagine using them to deliver specific drugs at well-defined locations in a living body. External fields can be used, for instance, to direct these assemblies by interaction with their magnetic portion, while tracking will be possible via their fluorescent part. Biomolecules attached to nanocrystals could be used to selectively target specific cells and thereby could enable the curing of cancer. Once the nanocrystals have accomplished their task, they could be re-concentrated by magnetic fields in another region of the body and then be extracted.
Selected publications:
"Sequential Growth of Magic-Size CdSe Nanocrystals."
Kudera, S., M. Zanella, et al., Advanced Materials (2007) 19(4): 548-552.
DOI: 10.1002/adma.200601015
"Formation of asymmetric one-sided metal tipped semiconductor
nanocrystal dots and rods", T. Mokari, C. G. Sztrum, A. Salant,
E. Rabani and U. Banin, Nature Materials 4, 855-863 (2005). (News & Views
by P.D. Cozolli and L. Manna, Nature Materials 4, 801-802 (2005) DOI:
(10.1038/nmat1505)
"Directed self assembly of gold-tipped semiconductor nanorods",
Asaf Salant, Ela Amitay-Sadovsky, Uri Banin, J. Am. Chem. Soc. 128 (31),
10006-10007 (2006). DOI: 10.1021/ja063192s
"Multiple Wurtzite Twinning in CdTe Nanocrystals Induced by Methylphosphonic
Acid." Luigi Carbone, Stefan Kudera, et al, J. Am. Chem. Soc.
(2006) 128: 748-755. DOI: 10.1021/ja054893c
“Level structure of InAs quantum dots in two-dimensional assemblies",
Dov Steiner, D. Azulai, Assaf Aharoni, Uri Banin, and Oded Millo, Nano
Lett. 6, 2201-2205 (2006). DOI: 10.1021/nl061410+
“Confined optical phonon modes in aligned nanorod arrays detected
by resonant inelastic light scattering” C. Nobile, V. A. Fonoberov,
et al., Nano Letters 7 (2), p. 476-479 (2007), DOI: 10.1021/nl062818+
