Atomic scale modeling of metallic nanoparticles embedded in nanoscale carbon structures (DFG)
Carbon nanotubes and nanoonions present extremly stable sp2 bonded networks. Recent experiments by transimission electron microscopy have shown, that these carbon allotropes provide a novel microscopic test environment for probing the deformation behavior of individual embedded metallic nanoparticles, because the annihilation of irradiation induced vacancies leads to a reduction of the radius of the carbon nanostructure and therefore induces mechanical stress states in the metallic nanoparticle. This methods paves the way, for studying the deformation behavior of individual nanocrytallites and therefore provides information, which will also help to understand deformation mechanisms of nanocrstystalline microstructure.
Since the TEM experiments provide information on the deformed state of the structures at given time, but no information on the deformation mechanisms occuring on short time scales, atomic scale computer simulations are necessary to provide complementary information.
Within this project, the mechanical properties of individual nanocrystallites embedded in nanoextruders consisting of carbon network are studied using atomistic simulation methods ranging from kinetic Monte Carlo method to quantum mechanic calculations based on density-functional theory. The combination of two nanosystems provides a unique opportunity to study the response of individual metal nanocrystals to mechanical deformation.
Dr. Antti Tolvanen, Prof. Karsten Albe