The ability to prepare solid surfaces with well-controlled superhydrophobic and superoleophilic properties is of paramount importance to water-oil separation technology. Herein, we successfully prepared superhydrophobic-superoleophilic membranes by single-step deposition of polystyrene (PS) nanofibers onto a stainless steel mesh via electrospinning. The contact angles of diesel and water on the prepared PS nanofiber membrane were 0° and 155° ± 3°, respectively. Applications of the PS nanofiber membrane toward separating liquids with low surface tension, such as oil, from water were investigated in detail. Gasoline, diesel, and mineral oil were tested as representative low-viscosity oils. The PS nanofiber membranes efficiently separated several liters of oil from water in a single step, of only a few minutes' duration. The superhydrophobic PS nanofiber membrane selectively absorbs oil, and is highly efficient at oil-water separation, making it a very promising material for oil spill remediation.

Self-junctioned copper nanofiber transparent flexible films are produced using electrospinning and electroplating processes that provide high performances of T = 97% and Rs = 0.42 Ω sq(-1) by eliminating junction resistance at wire intersections. The film remains conductive after being stretched by up to 770% (films with T = 76%) and after 1000 cycles of bending to a 5 mm radius.

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A highly transparent, flexible, patternable, and wearable heater by a single-step supersonic kinetic spraying.

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A highly transparent, flexible, stretchable and patternable copper fiber heater was successfully fabricated for potential use in smart windows and other applications. The thickness of the electrospun polymer nanofibers was controlled during subsequent copper plating by adjusting the electroplating time, with minimal sacrifice in transparency. Self-fused junctions, formed via electroplating, significantly reduced the contact resistance between the intersecting copper-plated fibers. The heater temperature remained constant up to 300% sheet stretching. De-icing tests confirmed the potential applicability of such heaters in smart windows or vehicle defrosters. The copper-plated fibers may be transferred onto any surface with a complex 3D structure, as demonstrated by fabricating a heat-radiating Venus statue covered with the copper-plated fibers. The highest temperature of 328°C was achieved by using a transparent fibrous film having 90% transparency and 0.058 Ω sq − 1 sheet resistance.

The present work contains the results of the experiments with two tiny drops on partially wettable substrates with contact angles of 10°, 24°, 27°, and 56°, which coalesce in the regime entirely dominated by viscous forces. Both side and bottom views are examined. The results for these three-dimensional coalescence flows are compared with scaling laws and the numerical two-dimensional model developed in the present work.

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