The tailoring of surface properties of metal oxide nanoparticles is highly important to exploit their benefits in an optimal way for diverse applications. For example, in polymer matrix nanocomposites one of the most critical aspects is the interaction of the particles with the matrix, which is determined by the chemistry of the particle surface and can be adjusted by attachment of organic ligands. Whilst many empirical solutions have been presented for specific combinations of particles and matrix, generalized approaches are not available yet. As a versatile and arbitrary method to permanently modify the surface of metal oxide nanoparticles, we present a two-step approach and prove its applicability for the versatile adjustment of surface properties of two types of nanoparticles.

The application of modified Al 2 O 3 nanoparticles for thin coatings is investigated to improve especially the mechanical characteristics by cross-linking the particles using an additive, together with the formulation parameters as well as the crosslinking kinetics. In general, the experiments demonstrate that the mechanical properties, like hardness and scratch resistance, can be enhanced via particle surface modification in combination with a cross-linking additive. Specifically, the optimal additive concentration was determined in order to obtain coatings with improved mechanical and constant optical properties. These results were related to the structure formation and cross-linking behavior. Mechanisms were identified for this series of experiments to explain how the particles bond with each other and how the coating structure is formed by using different additive ratios.

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Lithium-ion batteries (LIBs) provide the largest source of electrical energy storage today. This paper covers the use of comminution processes and, thus, crushers and mills for particle breakage and dispersing, as well as classifiers for particle separation within the process chain, from the raw material to the final lithium battery cell and its recycling at end of life. First of all, the raw materials for the active material production have to be produced either by processing primary raw materials, or by recycling the spent lithium batteries. The end-of-life battery cells have to be shredded, the materials separated and then milled in order to achieve the so-called black mass, which provides a secondary material source with very valuable components. Using these materials for the synthesis of the cathode active materials, milling has to be applied in different stages. The natural graphite, increasingly used as anode material, has to be designed in mills and classifiers for achieving targeted properties. Nanosized silicon is produced by nanomilling using stirred media mills as a primary option. Conductive additives for LIBs, like carbon black, have to be dispersed in a solvent with machines like planetary mixers, extruders or stirred media mills. In the future, mechanochemical synthesis of solid electrolytes will especially require additional application of comminution processes.