Chemical composition and shape determine the basic properties of any object. Commonly, chemical synthesis and shaping follow each other in a sequence, although their combination into a single process would be an elegant simplification. Here, a pathway of simultaneous synthesis and shaping as applied to polysiloxanes on the micro- and nanoscale is presented. Complex structures such as stars, chalices, helices, volcanoes, rods, or combinations thereof are obtained. Varying the shape-controlling reaction parameters including temperature, water saturation, and the type of substrate allows to direct the reaction toward specific structures. A general mechanism of growth is suggested and analytical evidence and thermodynamic calculations to support it are provided. An aqueous droplet in either gaseous atmosphere or in a liquid organic solvent serves as a spatially confined polymerization volume. By substituting the starting materials, germanium-based nanostructures are also obtained. This transferability marks this approach as a major step toward a generally applicable method of chemical synthesis including in situ shaping.

The synthesis of polysiloxane nanotubes using trifunctional organosilanes is reported. Tubular nanostructures were formed via a chemical vapor deposition technique at room temperature when ethyltrichlorosilane is used or via a liquid phase method when methyltriethoxysilane is used as precursor. In the chemical vapor deposition process the shape of the tubes was controlled by changing the water content in the reaction chamber prior to coating. The diameter varied between 60 and 4000 nm. While in the case of the liquid phase method nanotubes with very high aspect ratios of 800 are produced. Parameters, such as length and diameter of the various tubes, were investigated using scanning electron microscopy and transmission electron microscopy. Additionally, the chemical composition of produced structures was analyzed using attenuated total reflectance-infrared and energy-dispersive X-ray spectroscopy. Glass substrates coated with such structures exhibit extreme superhydrophobic properties.

Nanotechnology plays a central role in both academic research and industrial applications. Nanoenabled products are not only found in consumer markets, but also importantly in business to business markets (B2B). One of the oldest application areas of nanotechnology is nanocatalysis-an excellent example for such a B2B market. Several existing reviews illustrate the scientific developments in the field of nanocatalysis. The goal of the present review is to provide an up-to-date picture of academic research and to extend this picture by an industrial and economic perspective. We therefore conducted an extensive search on several scientific databases and we further analyzed more than 1,500 nanocatalysis-related patents and numerous market studies. We found that scientists today are able to prepare nanocatalysts with superior characteristics regarding activity, selectivity, durability, and recoverability, which will contribute to solve current environmental, social, and industrial problems. In industry, the potential of nanocatalysis is recognized, clearly reflected by the increasing number of nanocatalysis-related patents and products on the market. The current nanocatalysis research in academic and industrial laboratories will therefore enable a wealth of future applications in the industry.

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