We discuss the influence of surface structure, namely the height and opening angles of nano- and microcones on the surface wettability. We show experimental evidence that the opening angle of the cones is the critical parameter on sample superhydrophobicity, namely static contact angles and roll-off angles. The textured surfaces are fabricated on silicon wafers by using a simple one-step method of reactive ion etching at different processing time and gas flow rates. By using hydrophobic coating or hydrophilic surface treatment, we are able to switch the surface wettability from superhydrophilic to superhydrophobic without altering surface structures. In addition, we show examples of polymer replicas (polypropylene and poly(methyl methacrylate) with different wettability, fabricated by injection moulding using templates of the silicon cone-structures.

We demonstrate the use of roll-to-roll extrusion coating (R2R-EC) for fabrication of nanopatterned polypropylene (PP) foils with strong antiwetting properties. The antiwetting nanopattern is originated from textured surfaces fabricated on silicon wafers by a single-step method of reactive ion etching with different processing gas flow rates. We provide a systematic study of the wetting properties for the fabricated surfaces and show that a controlled texture stretching effect in the R2R-EC process is instrumental to yield the superhydrophobic surfaces with water contact angles approaching 160° and droplet roll-off angles below 10°.

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All‐solid‐state‐batteries (ASSB) are promising candidates for next generation lithium batteries providing high energy density and safety levels. Their success crucially depends on the properties of the available solid electrolyte materials, ideally offering sufficient conductivities in combination with stability against decomposition over a large electrochemical window. Therefore, the search for solid electrolytes with novel compositions remains of high interest. In this work we present a strategy to stabilize highly conductive lithium argyrodites by means of lithium substitution. This is different from the previously described possibilities to obtain stable structures by either substituting phosphorous or sulfide anions in the parent compound Li7PS6. This approach offers access to a new array of solid electrolyte candidates with an argyrodite‐type crystal structure. Conductivities of up to 1.4⋅10−4 S/cm can be obtained for Fe‐substituted materials of general composition Li7‐2xFexPS6.

We report a simple one-step maskless fabrication of inverted pyramids on silicon wafers by reactive ion etching. The fabricated surface structures exhibit excellent anti-reflective properties: The total reflectance of the nano inverted pyramids fabricated by our method can be as low as 12% without any anti-reflective layers, and down to only 0.33% with a silicon nitride coating. The results from angle resolved scattering measurements indicate that the existence of triple reflections is responsible for the reduced reflectance. The surfaces with the nano inverted pyramids also exhibit a distinct milky white color.

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