Interview with Dr. Alexander Schätz from the FML on radio Köln campus

Interview with Dr. Alexander Schätz from the FML laboratory about the application of nanoparticles.


Interview with Dr. Alexander Schätz on radio Köln campus (German).

Antibacterial films

Antibacterial films containing silver nanoparticles discovered by the FML laboratory implemented by Perlen Converting AG.


Einstein broadcast from SF1 (only in german).

Magnetic Hydrogel

The combination of force and flexibility is at the core of biomechanics and enables virtually all body movements in living organisms. In sharp contrast, presently used machines are based on rigid, linear (cylinders) or circular (rotator in an electrical engine) geometries. As a potential bioinspired alternative, magnetic elastomers can be realized through dispersion of micro- or nanoparticles in polymer matrices and have attracted significant interest as soft actuators in artificial organs, implants, and devices for controlled drug delivery. At present, magnetic particle loss and limited actuator strength have restricted the use of such materials to niche applications. We describe the direct incorporation of metal nanoparticles into the backbone of a hydrogel and application as an ultra-flexible, yet strong magnetic actuator. Covalent bonding of the particles prevents metal loss or leaching. Since metals have a far higher saturation magnetization and higher density than oxides, the resulting increased force/volume ratio afforded significantly stronger magnetic actuators with high mechanical stability, elasticity, and shape memory effect.

Ink-jet printable copper nanoparticles

New oxidation protection enables the use of copper nanoparticles in water-based inks for ink-jet printing of low-cost conductive patterns

Metal nano-dispersions have received tremendous attention for a wide range of applications. Metal oxidation, however, has traditionally restricted the range of useful nano-metals to silver, platinum, palladium and gold. Technical low cost applications such as ink jet printing of flexible conductors and radio frequency identification (RFID) tags, however, require manufacturing costs of typically less than one cent per tag. The most evident candidate to substitute silver or gold would be copper, but nano-copper rapidly oxidizes under ambient conditions. Stabilization of copper nanoparticles by a few graphene layers was realized on a technical scale and enables full protection of the copper metal core up to 200 °C under humid air. The protected copper can then be used in domestic ink jet printers for preparation of conductive patterns.

Features:
• Low-cost copper nanoparticles (scalable process)
• Water-based inks
• Printable by commercial ink-jet printers
• No need for post-treatment
• Electrical conductivity of 100 S/m
• Applications: RFID’s, car back-window heating, low-conduction applications

Highly magnetic polymers

Incorporation of carbon-coated cobalt nanoparticles into polymers leads to highly magnetic plastics

The in-situ graphene coating of metal nanoparticles is a highly technical innovation of the FML laboratory. Graphene coatings inhibit the rapid oxidation of such reactive nanoparticles and enable their use in new applications. For example air-stable graphene coated cobalt nanoparticles could be incorporated into polymers like PMMA which resulted in highly magnetic properties comparable to bulk cobalt. These highly magnetic composites are still polymer melt processable by low-cost fabrication techniques such as extrusion or injection-molding. Since the graphene coatings provide an oxidation stabilization the polymer composites can be heated up to 280°C without the rapid oxidation of the metallic cobalt phase.

Features:

• Polymer processing techniques applicable
• High metal loading of 90wt% possible
• Metallic appearance
• Electrical conductivity of around 5000 S/m
• Saturation magnetization of around 150 emu/g
• Low coercivity of 100 Oersted
• High thermal stability of 280°C
• Applications: Low-cost electric engines, microcomponents
  
  
  
• 

Link to the scientific publication

Nanograde GmbH: second FML spin-off

The idea has been growing in our minds for a long time, the first legal hurdles are being conquered and the website is under construction! Nanograde GmbH intends to sell oxide and salt nanoparticles on demand. Fast, reliable and worldwide!
The webshop will be launched 1st July 2008 on www.nanograde.net
For more information contact us: info@nanograde.net

ES&T’s Best Papers of 2007 by the FML

The scientific journal Environmental Science & Technology has awarded our paper by Limbach et al. on nanoparticle exposure as the ES&T’s Best Papers of 2007.

Read more in the news section of ES&T. The story was also covered by ETH life.