Synthesis

Synthesis of Nanoparticles

The so-called “bottom-up” methods are based on the controlled reaction of atoms, molecules or ions to larger entities. The advantage is that via these methods, smallest particles can be obtained that all possess practically identical size and shape (see image). Moreover, materials consisting of several components can be prepared with high homogeneity from the individual components after mixing at the molecular level, resulting in optimum materials quality.

In our research group, the synthesis is performed predominantly via the nonaqueous synthesis method, which is characterized by a slow, controlled reaction and is thus suitable for the preparation of nanoparticles with highest quality demand as well as the preparation of nanomaterials with complex composition. Thereby, a large variety of binary and ternary metal oxide nanoparticles can be obtained, for example TiO₂, ZrO₂, Fe₃O₄, BaTiO₃, BaSnO₃ or ITO (indium tin oxide). By the use of additives, doping of the materials is possible. Thus, we have e.g. achieved the synthesis of luminescent Eu³⁺-doped ZrO₂ nanoparticles. In the most cases, the reaction systems are highly robust and can be utilized for the preparation of larger amounts of nanoparticles also in the 1L scale – in contrast to many other methods, where the nanoparticles in desired size and shape can reproducibly only be obtained through a precise control of all process parameters.