Pancake bouncing on superhydrophobic surfaces

By Yahua Liu, Lisa Moevius, Xinpeng Xu, Tiezheng Qian, Julia M. Yeomans, Zuankai Wang. Nature Physics, 2014

922 citations recorded by the source corpus.

When a water drop bounces back from a hydrophobic surface, its initial, spherical shape is usually restored. Now, experiments with a specially engineered superhydrophobic surface made from micrometre-sized tapered pillars covered with copper oxide ‘nanoflowers’ show that droplets can bounce back with a flat, pancake-like shape. Engineering surfaces that promote rapid drop detachment1,2 is of importance to a wide range of applications including anti-icing3,4,5, dropwise condensation6 and self-cleaning7,8,9. Here we show how superhydrophobic surfaces patterned with lattices of submillimetre-scale posts decorated with nanotextures can generate a counter-intuitive bouncing regime: drops spread on impact and then leave the surface in a flattened, pancake shape without retracting. This allows a fourfold reduction in contact time compared with conventional complete rebound 1,10,11,12,13. We demonstrate that the pancake bouncing results from the rectification of capillary energy stored in the penetrated liquid into upward motion adequate to lift the drop. Moreover, the timescales for lateral drop spreading over the surface and for vertical motion must be comparable. In particular, by designing surfaces with tapered micro/nanotextures that behave as harmonic springs, the timescales become independent of the impact velocity, allowing the occurrence of pancake bouncing and rapid drop detachment over a wide range of impact velocities.

Subfields: Biomedical Engineering, Computational Mechanics, Surfaces, Coatings and Films

View Paper: https://www.semanticscholar.org/paper/eba9dbb3b4091e96d7277acc78028507e30fa4b8

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Biomedical Engineering

1. C. Josserand
2. Sigurdur T. Thoroddsen
3. Detlef Lohse

In Computational Mechanics

1. C. Josserand
2. Sigurdur T. Thoroddsen
3. Detlef Lohse
4. Gangtao Liang
5. I. Mudawar

In Surfaces, Coatings and Films

1. C. Josserand
2. Sigurdur T. Thoroddsen
3. Detlef Lohse
4. Gangtao Liang
5. I. Mudawar

Citations in the corpus

• Drop Impact on a Solid Surface (2016, positive): “Moevius et al. (2014) demonstrated what they call pancake rebound shown in Figure 4(b) .”