Research at the Institute of Materials Physics and Technology

Nanoscale Functional and Structural Materials:

The emerging concept of nanomaterials brings novel opportunities for materials design, which remain largely uncharted. There are also considerable challenges in adapting conventional materials systems for nanoscale components in microelectronic and microelectromechanical devices. The materials performance is here no longer controlled by the familiar properties of the bulk phases. Instead, the materials behaviour hinges on interface- and size effects that are at best partly understood. These issues are in the focus of the research at the Institut für Werkstoffphysik und Werkstofftechnologie (IWW). Based on a qualitatively improved understanding of the relevant science, we develop novel nanoscale functional and structural materials.

Materials Design:
The materials design at IWW hinges on coupling the microscopic processes at interfaces with the macroscopic materials behaviour. Examples are mechanical phenomena – such as actuation and strength – as well as chemical (catalysis, energy storage) and optical (photonics) properties. The approach opens new vistas for manipulating the materials behaviour by means of external control variables such as electric potential, the chemical environment, or mechanical forces. Furthermore, the trend of ‘smaller is stronger’, along with the low mass density of porous materials, suggests interesting perspectives for strong lightweight materials based on nanoporous metal. The relevant projects are complemented by approaches for designing modern magnesium alloys for lightweight applications.

Materials Physics Research:
The IWW research on materials physics relates to current and largely open scientific issues in the Nanosciences. These issues include the mechanisms of plastic deformation of aggregates of nanoscale objects and of materials with low lattice symmetry, the mechanics of interfaces and its coupling to the electrical and chemical potential and to catalysis, the nature of thermodynamic equilibrium and of equilibrium phases as well as themal stability in interface-controlled systems, and the coupling between charge transfer at metal surfaces on the one hand and the mechanical, optical, and chemical materials behaviour on the other. 

Nanoporous metals, such as his porous gold single crystal, promise manifold opportunities for application as functional or structural materials. They also provide ideal model systems for studies of interfaces and of interface-controlled materials behaviour.

Nanoporous metals, such as his porous gold single crystal, promise manifold opportunities for application as functional or structural materials. They also provide ideal model systems for studies of interfaces and of interface-controlled materials behaviour.

While macroscopic bodies are constrained to be quite precisely charge neutral, nanoscale object – such as this 309 atom gold cluster – can accumulate a significant electronic charge per atom. The unusual violation of the charge neutrality and the space-charge regions at the object surface are fascinating objects of study. The ensuing effects may be exploited for designing nanomaterials with novel functional properties.

While macroscopic bodies are con- strained to be quite precisely charge neutral, nanoscale object – such as this 309 atom gold cluster – can accumulate a significant electronic charge per atom. The unusual violation of the charge neutrality and the space-charge regions at the object surface are fascinating objects of study. The ensuing effects may be exploited for designing nano- materials with novel functional proper- ties.

Current Research Topics - Examples: