15 October 2017
Tough and strong: nanocomposite with exceptional properties
Published online 12 February 2016
New nanocomposite material combines the hardness and strength of minerals and the multifunctionality of organics.
A team of researchers managed to produce crystals of tiny, almost spherical, nanoparticles linked together by an organic material with superior mechanical properties.
Minerals are hard, whereas organic materials are soft. Composite materials made of both are versatile and multifunctional. Nanoparticle supercrystals made of hard inorganic nanoparticles linked together by soft organic materials are one such type of composite material.
Until this research, the desired hardness and strength was never achieved.
The researchers from Germany, The Netherlands and Saudi Arabia devised a strategy to make supercrystals of iron oxide (Fe3O4) nanoparticles linked together by an organic acid, oleic acid, with unprecedented hardness, elasticity and strength.
They used Fe3O4 nanoparticles attached to the long-hydrocarbon-chain oleic acid and assembled them by slowly evaporating the surrounding solvent, bringing the particles together. Then, they applied heat to trigger the formation of cross-links between the individual oleic acid chains, making a network.
“Two aspects of this new nanocomposite are momentous: First, the nanostructure resembles that of some types of natural hard tissue so a biological application as substitute material is conceivable. Secondly, typical inorganic material properties like the magnetic or semiconducting behavior can be combined in a controlled way with typical organic material properties like chemical reactivity and variety. This could open a new wide research field.” says Axel Dreyer, the lead author of the paper published in Nature Materials1 .
- Dreyer, A. et al. Organically linked iron oxide nanoparticles supercrystals with exceptional isotropic mechanical properties. Nature Materials http://dx.doi.org/10.1038/nmat4553 (2016).