Dataset Information

Self-removal of condensed water on the legs of water striders.

ABSTRACT: The ability to control drops and their movements on phobic surfaces is important in printing or patterning, microfluidic devices, and water-repellent materials. These materials are always micro-/nanotextured, and a natural limitation of repellency occurs when drops are small enough (as in a dew) to get trapped in the texture. This leads to sticky Wenzel states and destroys the superhydrophobicity of the material. Here, we show that droplets of volume ranging from femtoliter (fL) to microliter (?L) can be self-removed from the legs of water striders. These legs consist of arrays of inclined tapered setae decorated by quasi-helical nanogrooves. The different characteristics of this unique texture are successively exploited as water condenses, starting from self-penetration and sweeping effect along individual cones, to elastic expulsion between flexible setae, followed by removal at the anisotropic leg surface. We envision that this antifogging effect at a very small scale could inspire the design of novel applicable robust water-repellent materials for many practical applications.

SUBMITTER: Wang Q

PROVIDER: S-EPMC4522788 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Self-removal of condensed water on the legs of water striders.

Wang Qianbin Q Yao Xi X Liu Huan H Quéré David D Jiang Lei L

Proceedings of the National Academy of Sciences of the United States of America 20150713 30

The ability to control drops and their movements on phobic surfaces is important in printing or patterning, microfluidic devices, and water-repellent materials. These materials are always micro-/nanotextured, and a natural limitation of repellency occurs when drops are small enough (as in a dew) to get trapped in the texture. This leads to sticky Wenzel states and destroys the superhydrophobicity of the material. Here, we show that droplets of volume ranging from femtoliter (fL) to microliter (μ ...[more]

PMID: 26170300

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Dataset Information

Self-removal of condensed water on the legs of water striders.

Publications

Self-removal of condensed water on the legs of water striders.

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