Fabrication of artificial Lotus leaves and significance of hierarchical structure for superhydrophobicity and low adhesion

Koch, Kerstin; Bhushan, Bharat; Jung, Yong Chae; Barthlott, Wilhelm

doi:10.1039/b818940d

Cited by 632 publications

(477 citation statements)

References 41 publications

Supporting

Mentioning

452

Contrasting

Unclassified

Order By: Relevance

“…79 The now commonly accepted meaning of a superhydrophobic surface is a surface on which the water (advancing) contact angle is at least 150°, and the contact angle hysteresis as well as the sliding (or rolling off) angle (sliding/rolling angle is the minimum angle of sloped solid at which water (liquid) drop rolls off the surface) do not exceed 5-10° (Table 2). Although currently superhydrophobic surfaces are inspired by biological specimens, [80][81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97] the early research was inspired by the practical need to enhance coating repellency of water and snow. 98,99 These days, superhydrophobic coatings are manufactured by chemical, physical and/or mechanical modifications of both organic and inorganic materials.…”

Section: 78mentioning

confidence: 99%

Physics and applications of superhydrophobic and superhydrophilic surfaces and coatings

Drelich

Marmur

2014

Surface Innovations

155

View full text Add to dashboard Cite

The terms superhydrophobicity and superhydrophilicity were introduced not very long ago, in 1996 and 2000, respectively.The former is used to describe exceptionally weak and the latter used to indicate strong interactions of materials and IntroductionAfter more than two centuries of research, capillarity and wetting phenomena still remain popular topics of investigation in many modern surface chemistry laboratories. Curiosity and fascination with rain droplets splashing in a puddle, water droplets decorating flowers, leaves of plants and fruits after rain or watering and colorful soap bubbles shaped at the end of wheat straw have never been stronger and go beyond scientific laboratories. Colorful images of liquid droplets and puddles, illustrating their behavior on a variety of surfaces, thrive in professional journals, popular magazines and Internet. However, terms such as wetting, spreading and contact angle are still puzzling to the layman and beginner researcher. To facilitate

show abstract

Section: 78mentioning

confidence: 99%

Physics and applications of superhydrophobic and superhydrophilic surfaces and coatings

Drelich

Marmur

2014

Surface Innovations

155

View full text Add to dashboard Cite

show abstract

“…The authors demonstrated that the epidermal, outermost, cells of the lotus leaves form papillae, which act as microstructure roughness. The papillae are superimposed by a very dense layer of epicuticular waxes (wax crystals), also referred to as hair-like structures [32] or nanostructure roughness [33]. Figure 1 shows different degrees of magnification from zero to 10 6 of a lotus leaf using SEM images.…”

Section: Lotus Leavesmentioning

confidence: 99%

Polymeric Slippery Coatings: Nature and Applications

Samaha

Gad‐el‐Hak

2014

Polymers

View full text Add to dashboard Cite

Abstract:We review recent developments in nature-inspired superhydrophobic and omniphobic surfaces. Water droplets beading on a surface at significantly high static contact angles and low contact-angle hystereses characterize superhydrophobicity. Microscopically, rough hydrophobic surfaces could entrap air in their pores resulting in a portion of a submerged surface with air-water interface, which is responsible for the slip effect. Suberhydrophobicity enhances the mobility of droplets on lotus leaves for self-cleaning purposes, so-called lotus effect. Amongst other applications, superhydrophobicity could be used to design slippery surfaces with minimal skin-friction drag for energy conservation. Another kind of slippery coatings is the recently invented slippery liquid-infused porous surfaces (SLIPS), which are one type of omniphobic surfaces. Certain plants such as the carnivorous Nepenthes pitcher inspired SLIPS. Their interior surfaces have microstructural roughness, which can lock in place an infused lubricating liquid. The lubricant is then utilized as a repellent surface for other liquids such as water, blood, crude oil, and alcohol. In this review, we discuss the concepts of both lotus effect and Nepenthes slippery mechanism. We then present a review of recent advances in manufacturing polymeric and non-polymeric slippery surfaces with ordered and disordered micro/nanostructures. Furthermore, we discuss the performance and longevity of such surfaces. Techniques used to characterize the surfaces are also detailed. We conclude the article with an overview of the latest advances in characterizing and using slippery surfaces for different applications.

show abstract

“…20, and nonwettability, ref. 21), but it is less widely realized that complex topographies also provide new approaches to wetting state switching by giving rise to a larger number of wetting states, making the term "Cassie state" less well defined: there exist several possible states that involve trapped air, but vary in terms of wetted solid fraction and the volume of the air layer (4,22,23). Wetting hysteresis depends on the amount of wetted solid, so states with little wetting are of particular interest for designing bistable systems.…”

mentioning

confidence: 99%

Reversible switching between superhydrophobic states on a hierarchically structured surface

Verho

Korhonen

Sainiemi

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

263

258

View full text Add to dashboard Cite

Nature offers exciting examples for functional wetting properties based on superhydrophobicity, such as the self-cleaning surfaces on plant leaves and trapped air on immersed insect surfaces allowing underwater breathing. They inspire biomimetic approaches in science and technology. Superhydrophobicity relies on the Cassie wetting state where air is trapped within the surface topography. Pressure can trigger an irreversible transition from the Cassie state to the Wenzel state with no trapped air-this transition is usually detrimental for nonwetting functionality and is to be avoided. Here we present a new type of reversible, localized and instantaneous transition between two Cassie wetting states, enabled by two-level (dual-scale) topography of a superhydrophobic surface, that allows writing, erasing, rewriting and storing of optically displayed information in plastrons related to different length scales.micropillars | silicone nanofilaments | optical data storage | bistable | two-tier

show abstract

Fabrication of artificial Lotus leaves and significance of hierarchical structure for superhydrophobicity and low adhesion

Cited by 632 publications

References 41 publications

Physics and applications of superhydrophobic and superhydrophilic surfaces and coatings

Physics and applications of superhydrophobic and superhydrophilic surfaces and coatings

Polymeric Slippery Coatings: Nature and Applications

Reversible switching between superhydrophobic states on a hierarchically structured surface

Contact Info

Product

Resources

About