Posted: September 6, 2007

Nanococktails from the laser bar: The production of pure nanomaterials by laser ablation in liquids

(Nanowerk News) As measured by the patents in Europe, Nanotechnology is considered as motor for the future of energy, environmental, information and medical technology. Nanostructures have particular properties that differ from those of “the big ones”. Nanoparticles of gold, for instance, have a reddish color, ceramic nanoparticles invisibly provide for scratch-resistant car paints, and nanoparticles of silver protect against infections and diseases. Usually, these particles are produced by chemical means in the gaseous or liquid phase, which can lead to agglomerations or impurities by adjuvants such as precursors and additives. For sophisticated applications in plastics and medical technology, however, highly pure and stable particles are required. Furthermore, users often require nanoparticles of new materials and alloys, as well as mixtures of nanoparticles for the combination of nanoeffects. But how can such nanomaterials be produced rapidly and of highly pure quality?
At the Laser Zentrum Hannover e.V. (LZH), laser technology is used to generate nanoparticles. The laser “blasts” the nanoparticles out of a substrate surface – the engineer calls this material ablation – directly into a suitable liquid such as oil, water, or solvent, which at the same time stabilizes the precious and highly sensitive nanomaterial. One particularity of this procedure is that any solid material can be “chopped” this way, thus hardly any conceivable application-specific nanomaterial mixture can be produced. Or to put it this way: This procedure allows to mix nanococktails by combining optional ingredients according to a “recipe”. This is particularly important for making use of the nanoeffects in further processes to produce plastic parts or medical products.
The procedure – also known as Rapid Nanomaterial Manufacturing – enables the production of stable nanoparticles, as well as their lossless embedding (complete dispersion) into a desired plastic material. Since the procedure does not require the use of chemical adjuvants, the product is particularly pure, thus free from possible uncontrollable effects, quality deviations, or secondary effects.
The nanococktails as well as information on the production and application of nanomaterials will be displayed at the booth of the LZH during the Hannover Messe (April 16-20, 2007).
Source: Laser Zentrum Hannover