I am interested in the theoretical and computer simulation aspects of Nanoengineering, especially in designing and controlling nanoscale features of materials to achieve enhanced and new macroscopic properties or even new materials. The ultimate goal of Nanoengineering is to design materials specific sets of macroscopic properties by controlling their nanoscale building blocks and the interactions between them. One exciting example for such nanoscale building blocks are carbon nanotubes because of their unique combination of properties. Their high mechanical strength, high thermal and, in the case of metallic tubes, electrical conductivity making them very interesting for many nanotechnology applications, e.g. in nano-machines, as actuators which are stronger and having a work distance higher than natural muscle fibres, for field emitters, for medical application, e.g. as bone scaffold and for ultra high strength lightweight materials.
My specific interest is in materials which consist (almost) only of CNTs such as CNT papers because of their combined light weight and (potentially) high mechanical strength. The nanotubes in a CNT paper are randomly arranged - similar to the fibres of "normal" paper. This makes CNT papers good candidates for bulk materials because their random structure can be extended in all three spatial dimensions. The key problem, which currently prevents the utilization of CNT papers, is insufficient load transfer between the nanotubes.
My reseach is focused on developing methods to increase the load transfer in CNT materials. It appears that the most efficient way to do this is to enhance the load transfer at the nanoscale, i.e. between individual nanotubes. To protect the CNT material's unique properties this should be done by using as little foreign material as possible. Considering the small size of the contact area between CNTs, computer simulation methods are ideally suited to study the load transfer between individual CNTs at the nanoscale.
Computer simulations of these very heterogeneous systems are, however, challenging. The central problem is the simultaneous appearance of very different but relevant length and time scales. This requires the utilization of multiscale simulation methods. At present, no universal multiscale method exists. Therefore another aspect of my research is the development and advancement of multiscale simulation methods and coarse graining schemes.
Thus my research is focused on two subject areas:
- Computer simulations of carbon nanotube materials to design ways to enhance their mechanical properties.
- Design and advancement of multiscale simulation and coarse graining methods to tackle the problem above.