The work group synthesises a wide range of different nanoparticles. The materials as well as sizes and shapes are varied.
The optimisation of the synthesis parameters is investigated both in batch syntheses and in syntheses in flow reactors. Anisotropic nanoparticles can be achieved by kinetic and thermodynamic influences as well as the ligands used. The anisotropy has further influences on the physical properties of the resulting materials and their superstructures.
In addition to ligands, the combination of many materials in individual nanostructures is another important field of work. The heterostructures contain at least two different materials or material classes either showing a combination of properties of the separate materials or exhibiting completely new properties.
Investigations are made on ligands that enable integration into polymer structures and binding to biological materials.
A selection of the materials are various metals, semiconductors and metal oxides as well as lead halide perovskites and transition metal chalcogenides.
All nanoparticles are examined using different investigation methods. These include spectroscopic, electron microscopic, X-ray, electrochemical and magnetic measurement methods.
Many of these nanoparticles are converted into superstructures using different methods. For example, one method pursued is self-assembly. Various gelling methods are also carried out and investigated with many of the different nano structures. The influence of parameters especially the ligands on the formation of superstructures is another important field of investigation.
The different structures, from two to three-dimensional, in crystalline and amorphous structure from the various nanoparticles as building blocks lead to surprising new properties and collective behaviours. These range from optical properties, for example photonic properties, to catalytic, magnetic, electrochemical and sensory properties.
The transfer into different aero, cryoaerogels and hydrogels leads to structures that enable contact between the nanocrystals and thus interesting mobilities of the charge carriers. This mobility is analysed using impedance spectroscopy and cyclic voltammetry.
These structures enable the construction of devices that can act as sensors and offer interesting possibilities for photo catalysis.
In order to construct these devices, it is first necessary to construct the substrates for the subsequent electrical contacting.
The sensor responses to different analytes are investigated as well as different factors that influence these responses. The deposition as thin films of the nanoparticles enables to understand the underlying sensing mechanism.
Photo electrochemical and photo catalytic investigations of the huge variety of materials is an important goal of the work group.
