Microstructures and grease layer of water strider and its influence on superhydrophobicity

Abstract

In this paper, the microstructures of the water strider surface were observed by scanning electron microscopy. The surfaces, including wings, legs, back and abdomen, all exhibited various compound microstructures, which are the important factors influencing the superhydrophobicity with a contact angle (CA) of up to 153°. Furthermore, the grease of the water strider on different substrates was studied by self-assembly of the grease for 14 d. Images of the grease indicated that the morphology and spatial orientation of the grease depend on the substrate chosen. The grease decreased the substrate wettability by approximately 30° on highly ordered pyrolytic graphite and about 23° on the silicon substrates. Gas chromatography combined with mass spectrometry was also used to study the chemical composition of the grease layer of water strider surface. The grease layer is composed of a mixture of aliphatic compounds, which possess hydrophobicity based on the chemical structure. Grease protects the microstructures of water strider surfaces and thus results in higher CAs and hydrophobic properties. The microstructure and the grease of the water strider jointly render the hydrophobic properties of the water strider surface.

Superhydrophobic silicone rubber surface prepared by direct replication

“…The wonder of nature has endowed many animals and plants with superhydrophobic abilities, such as the wings of butterflies [1] and dragonflies [2], the legs of water striders [3], taro leaves [4] and lotus leaves [5]. The contact angle with water is greater than 150° and the rolling angle is less than 10° to be called superhydrophobic material [6,7].…”

Areas of green tribology: A review

“…Scientists and engineers have studied this effect to develop water-repellent materials that can be used in various applications, such as selfcleaning surfaces, anti-fouling coatings for ships, and waterproof clothing. The water strider effect has also inspired the development of small robots that can walk on water, which can be used for monitoring water quality or performing environmental surveys [13]. Sandfish lizard effect.…”

Advanced Bio‐Inspired Mechanical Sensing Technology: Learning from Nature but Going beyond Nature

“…Water striders have been known as insect hunters on water, feeding on bees, ladybugs, dragonflies, and other insects that fall on the water's surface. The study of superhydrophobic function inspired by micro-and nano-structures of legs, [71] the improvement of bionic water strider robot structures by their fast-moving gait, [72,73] and the fine biomechanics of water strider during movement [74] are all areas of current scientific research on water strider. However, nothing would be known about the method by which water strider avoids natural predators and catch their prey.…”