In addition to the research areas “Nanoparticle Characterization” and “Model Nanoparticles”, the project “Nanofluidics and Particle manipulation” is part of the research line “Quantum and Nanometrology (Quanomet)”. Here, the thematic focus is on the field “NanoParticles”, which, together with the fields “NanoLight” and “QuantumTechniques”, are the common objectives of “Measuring in the nano world” in cooperation with the Leibniz Universität Hannover. Thus, the main task of this project is to register nanoparticular structures metrologically and, above all, to understand the organizational processes in their entirety. In order to achieve this aim, aggregate structures have to be synthesized, as well as their formation and aggregation mechanisms have to be characterized and manipulated with the aid of nanofluidic systems. For this purpose, investigations are carried out on particle-particle and particle-wall interactions, hydrodynamic and electrokinetic transport phenomena and the separation of model structures. Therefore, special modular nanofluidic systems have to be constructed and the processes and structures have to be characterized with integrated electronic and optical precision measurement technology.
Within the scope of the working group “Production and characterization of hierarchical, metrological nano- and microstructures”, the main objectives are the setting of defined properties of aggregate structures such as number of particles, structure and morphology as well as an extension of the current state of knowledge on self-assembly processes of nanoparticles in fluidic systems. For this, two different approaches will be investigated. On the one hand, hierarchical structures have to be constructed from single-line chain segments. As building blocks, inorganic nanoparticles, such as silica or gold, have to build up to core / shell particles with the aid of polymers and transformed into single-line chain segments by specific formulation and process parameters. After subsequent classification of the segments, these have to be further processed by using other additives / particles to form larger aggregate structures (see Figure 1a). On the other hand, liquid crystals should be used as templates for the targeted structure formation. In certain temperature ranges and solvents, some organic substances form liquid-crystalline phases which have both a long-range order such as crystals and the mobility of liquids. Thus, liquid crystals can show a variety of ordered structures which should be used for the targeted organization of nanoparticles (see Figure 1b).
(a) (b)
Figure 1: Schematic representation of the aggregate structures of nanoparticulate building blocks with defined properties by (a) structure of single-line chain segments and (b) with the aid of liquid-crystalline phases as templates.