May 17, 2007
Self-assembly of colloidal nanocrystals makes it possible to obtain structures with a high level of ordering and enables construction of patterns that can be used in optoelectronics, photonics and biosensing. Thermodynamically driven self-organization processes allow large-scale production of nanowires or ordered 2D or 3D superlattices with very little infrastructural investment.
The technology was developed by researchers at the University of Reims Champagne-Ardenne (URCA). It is based on the fact that the nanocrystal properties that are essential to the arrangement process (including size, shape, surface protection and charge) can be controlled, along with the electronic structure of each nanocrystal. The researchers demonstrated that, under carefully selected conditions, the droplets of the aqueous solutions of water-solubilized CdSe/ZnS nanocrystal quantum dots and quantum rods are operating as a "lab-in-a-drop", in which a variety of nanostructures with desired properties may be produced.
The operation of the lab-in-a-drop may be controlled by external parameters, providing the fluorescent nanostructures of desired size, morphology and optical and energy transfer properties. Although a majority of the results were obtained with the CdSe/ZnS quantum dots and rods, similar nanocrystalline patterns may be produced in the aqueous suspensions of other nanocrystals. The entire process has been reported in Nanotechnology.
This work is a collaboration between URCA, Trinity College Dublin, Munich University and two Russian scientific centres, University of Informational Technologies, Mechanics and Optics, St Petersburg, and Shemyakin Institute of Bio-organic Chemistry, Russian Academy of Sciences, Moscow. Future work will include the development of self-healing polymers based on nanocrystal self-assembly and the application of designed nanostructures to biophotonics and to the engineering of energy harvesting and energy-transfer nano-devices operating in a FRET regime.
About the author
Igor Nabiev is a full professor and head of the nano-biotechnology group at the department of nanotechnological detection and therapeutic approaches in biological mechanisms of defence, Faculty of Medicine, University of Reims Champagne-Ardenne, France. He is currently conducting research projects on the development of novel cancer nano-diagnostic strategies and approaches to nanocrystal self-assembly.