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Search for "superhydrophobic" in Full Text gives 57 result(s) in Beilstein Journal of Nanotechnology.
Biomimetics on the micro- and nanoscale – The 25th anniversary of the lotus effect
Beilstein J. Nanotechnol. 2023, 14, 850–856, doi:10.3762/bjnano.14.69
- “Purity of the sacred lotus” [1] in which they described the superhydrophobic surfaces and the self-cleaning ability of some plants (the so-called “lotus effect”, see Figure 1). This paper led to a paradigm shift in surface sciences. It generated a lot of interest at the time and continues today to
- inspire numerous publications and technical developments [2]. Although the phenomenon of the outstanding water repellence of some plant surfaces had been known for over 2000 years, the functional principle behind it and the detailed physicochemistry of superhydrophobic biological surfaces had remained
- biomimetics and provide an overview of the development of superhydrophobic and self-cleaning biological and bioinspired surfaces over the past 25 years. The field that today is called “biomimetics” is almost as old as human history. Many examples in the literature show that in the early days of humankind the
The origin of black and white coloration of the Asian tiger mosquito Aedes albopictus (Diptera: Culicidae)
Beilstein J. Nanotechnol. 2023, 14, 496–508, doi:10.3762/bjnano.14.41
- appearance. The results suggest that mosquito scales, in addition to their superhydrophobic function, produce structural white. The biological role of white and black patches in mate recognition and defensive behaviour in the mosquitoes of the genus Aedes is hypothesized. Keywords: biological optics
- white bright scales on the body of Ae. albopictus are constituted of transparent cuticle, and their micro- and nanostructures can generate structural white. These results suggest a multifunctional role of the mosquito scales which, in addition to a superhydrophobic function [11][12][13], produce
Dry under water: air retaining properties of large-scale elastomer foils covered with mushroom-shaped surface microstructures
Beilstein J. Nanotechnol. 2022, 13, 1370–1379, doi:10.3762/bjnano.13.113
- Holzgerlingen, Germany 10.3762/bjnano.13.113 Abstract Superhydrophobic surfaces are well known for most different functions in plants, animals, and thus for biomimetic technical applications. Beside the Lotus Effect, one of their features with great technical, economic and ecologic potential is the Salvinia
- superhydrophobic surfaces and self-cleaning properties are available on the market [1][6][7]. A most interesting feature of certain superhydrophobic surfaces is their ability to maintain a persistent air layer submerged under water. This ability is called Salvinia effect [5][8][9][10]. Due to the hydrophobic
Straight roads into nowhere – obvious and not-so-obvious biological models for ferrophobic surfaces
Beilstein J. Nanotechnol. 2022, 13, 1345–1360, doi:10.3762/bjnano.13.111
- with hierarchically structured wax crystals, would represent “ready-made” models of superhydrophobic surfaces with versatile technical applications. The Lotus effect indeed proved to be attractive for applied sciences (as this special issue demonstrates), and its underlying physics was thoroughly
- studied. Subsequently, more water-repellent biological structures were identified, with additional features and, therefore, higher and novel application potential [2][3]. For instance, various biological surfaces were described that are not only superhydrophobic but are additionally able to keep
- persistent air layers for an extended time after immersion in water. Principally, superhydrophobic surfaces are commonly surrounded by air when immersed. However, the air body is not persistent enough for most applications and dissolves after some time, in contrast to surfaces that can be described as
Roll-to-roll fabrication of superhydrophobic pads covered with nanofur for the efficient clean-up of oil spills
Beilstein J. Nanotechnol. 2022, 13, 1228–1239, doi:10.3762/bjnano.13.102
- (KNMFi), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany 10.3762/bjnano.13.102 Abstract Superhydrophobic surfaces, which self-clean through rinsing with water, have gained significant importance during the last decades. A method to
- , too [7]. Multiple techniques exist to prepare self-cleaning surfaces. Direct laser writing and electron beam lithography have been employed successfully to create superhydrophobic surfaces. However, due to low writing speeds these approaches are not viable for surface areas larger than a few square
- millimeters [8][9]. Various (soft) lithography techniques have been employed to create superhydrophobic surfaces; however, these generally rely on copying surface information from a master (e.g., a lotus leaf) [9][10] and are therefore often limited in size. Superhydrophobic surfaces could also be prepared
Design of a biomimetic, small-scale artificial leaf surface for the study of environmental interactions
Beilstein J. Nanotechnol. 2022, 13, 944–957, doi:10.3762/bjnano.13.83
- °), hydrophobic (90° ≤ θ < 150°), and superhydrophobic (150° ≤ θ < 180°) [27]. Due to its chemical composition, the cuticle is generally a hydrophobic surface. However, plant surfaces show a large variability of cell shapes, surface structures, and hierarchical structures (a combination of micro- and
- nanostructures) [27]. Due to this structural diversity and different chemical modifications, plant surfaces can have different wetting properties, ranging from superhydrophobic to superhydrophilic [28]. An overview of the diverse microstructures and their influence on the wettability of plant surfaces is given
- inclined plane. The angle of inclination at which a droplet starts to roll off is called the TA α. Superhydrophobic surfaces with a low TA (α < 10°) and a small CAH have the ability to self-clean [9]. This property is also known as the Lotus effect, named after the best-known example of a self-cleaning
Bioselectivity of silk protein-based materials and their bio-inspired applications
Beilstein J. Nanotechnol. 2022, 13, 902–921, doi:10.3762/bjnano.13.81
- nanostructured ultrahydrophobic surfaces with self-cleaning ability, such as Lotus leaves and insect wing analogues [53][54][55], and the superhydrophobic air-retaining surfaces of Salvinia floating fern leaves and of the water bug Notonecta glauca [53][56]. Based on such blueprints, bioinspired anti-adhesion
- cells but to even display antiviral attachment properties [58]. Superhydrophobic surfaces inspired by the Lotus-effect® (>150° contact angle) have been found to diminish bacterial adhesion due to reduced protein surface adsorption [59][60][61]. Superhydrophobicity relies on the combination of chemical
- composition, surface structuring on the micro-/nanoscale, and the introduction of low-surface-energy compounds [62]. Various studies demonstrated that the adhesion of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli (E. coli) bacteria was significantly reduced on superhydrophobic coatings
Hierachical epicuticular wax coverage on leaves of Deschampsia antarctica as a possible adaptation to severe environmental conditions
Beilstein J. Nanotechnol. 2022, 13, 807–816, doi:10.3762/bjnano.13.71
- ., Asclepiadaceae and Cactaceae) [15], plays a crucial role in the protection from water loss. Biomimetic potential Since the discovery of the lotus effect [43], different properties of superhydrophobic surfaces in plants, which are highly relevant for modern technologies, such as self-cleaning, fluid drag
- projections. This, in turn, helps to keep an air layer between the wax particles under conditions of reduced water vapor. Moreover, superhydrophobic surfaces in combination with strong air flow can lead to newly formed ice particles being blown off, since the real contact area and, consequently, the adhesion
A comprehensive review on electrospun nanohybrid membranes for wastewater treatment
Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10
- ]. Su et al. have developed a superhydrophobic PVDF electrospun membrane for MD, which showed exceptional properties [56]. The membrane exhibited a significant antifouling property, stable permeate flux and little scaling or deposition of hard mineral salts on the membrane. In another study Kim and co
- water-in-oil emulsions superhydrophobic/superoleophilic membranes are used in which oil is permeated through the membrane while water is rejected [66]. Obaid et al. have electrospun a PSF solution mixed with NaOH nanoparticles in order to obtain a hydrophilic oil separating membrane [67]. The PSF
- surfactant-stabilized emulsions, respectively, was observed and obtained solely under the force of gravity [69]. Shang et al. developed superhydrophobic and superoleophilic nanofibrous membranes from electrospun CA with a novel in situ polymerized fluorinated polybenzoxazine (F-PBZ) functional layer with
A review on slip boundary conditions at the nanoscale: recent development and applications
Beilstein J. Nanotechnol. 2021, 12, 1237–1251, doi:10.3762/bjnano.12.91
- boundary conditions [10][11][12][13][14][15]. For example, many studies have shown that on hydrophobic surfaces, roughness may lead to a transition to a superhydrophobic state, significantly lowering the ability of liquid drops to stick. In other words, liquids can easily slip along such solid surfaces and
- the superhydrophobic state [44][88][89][90][91]. 2.4 Surface chemistry effects A substantial number of studies have demonstrated that complex surfaces decorated with a sophisticated surface chemistry can dramatically affect the effective slip length for nanoscale flow systems. The surface textures we
- . Investigating the effect of gas bubbles on the effective slip length is also of great value especially in the design and optimization of superhydrophobic surfaces, which have lots of applications due to their superlubricating potential [112][113][114]. The liquid flow behavior on such surfaces can be described
Self-assembly of Eucalyptus gunnii wax tubules and pure ß-diketone on HOPG and glass
Beilstein J. Nanotechnol. 2021, 12, 939–949, doi:10.3762/bjnano.12.70
- multifunctional wax coating on their surfaces made of branched ß-diketone tubules. ß-diketone tubules have a different size, shape, and chemical composition than the well-described nonacosanol tubules of the superhydrophobic leaves of lotus (Nelumbo nucifera). Until now the formation process of ß-diketone tubules
- structure [13][18]. Secondary alcohol tubules evolved in all major groups of land plants and design durable superhydrophobic surfaces (e.g., the Lotus Effect). In vitro recrystallization experiments with single wax components of these tubules showed that tubules were formed by secondary alcohols plus at
Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications
Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64
An investigation on the drag reduction performance of bioinspired pipeline surfaces with transverse microgrooves
Beilstein J. Nanotechnol. 2020, 11, 24–40, doi:10.3762/bjnano.11.3
- [7][8][9], the injection of gas to modify the turbulent boundary characteristics [10], and the fabrication of superhydrophobic surfaces to reduce the adhesion [11]. However, the application of polymer additives is not economic and the antidrag performance of additives is also instable under some
pH-Controlled fluorescence switching in water-dispersed polymer brushes grafted to modified boron nitride nanotubes for cellular imaging
Beilstein J. Nanotechnol. 2019, 10, 2428–2439, doi:10.3762/bjnano.10.233
- toxicity [21][22][23][24]. They are superhydrophobic in their pristine state and cannot be dispersed in aqueous media or in most organic solvents [11][22][23]. To improve the dispersibility of BNNTs in aqueous media, numerous surface functionalization methods have been used [11][25][26][27]. The
Nanostructured and oriented metal–organic framework films enabling extreme surface wetting properties
Beilstein J. Nanotechnol. 2019, 10, 1994–2003, doi:10.3762/bjnano.10.196
- for their survival in extreme conditions [1][2][3][4]. In plants, the unique surface architecture of the lotus leaf enables superhydrophobic and self-cleaning properties for sustaining efficient photosynthesis, even in polluted environments [5][6][7]. In the realm of animals, mosquitos utilize an
- properties and functions, MOFs are intriguing candidates for the design and synthesis of coatings combining a superhydrophilic, superhydrophobic, superoleophilic or superoleophobic character with desired features such as light filtering, hosting cavities, electrical conductivity, etc. In the literature, the
Rapid, ultraviolet-induced, reversibly switchable wettability of superhydrophobic/superhydrophilic surfaces
Beilstein J. Nanotechnol. 2019, 10, 866–873, doi:10.3762/bjnano.10.87
- superhydrophobic (WCA ≈ 165°) to a superhydrophilic (WCA ≈ 0°) state within 10 min upon UV illumination and subsequent recovery to superhydrophobicity occurred after heat treatment. It was found that the changes in the trimethoxy(alkyl)silane upon UV illumination can explain the rapid decrease of the WCA from more
- understanding, the effect of the trimethoxy(alkyl)silane concentration on the number of recycle cycles was investigated. Keywords: superhydrophilic surfaces; superhydrophobic surfaces; switchable wettability; TiO2; trimethoxy(alkyl)silane; UV illumination; Introduction Wettability is an important property of
- surfaces in a suspension of TiO2 modified with trimethoxypropyl saline. In this work, the wettability transition time from superhydrophobic (WCA ≈ 158°) to superhydrophilic (WCA ≈ 0°) occurred within 120 min of UV illumination. Although large range wettability switching can be achieved in many ways, the
Novel reversibly switchable wettability of superhydrophobic–superhydrophilic surfaces induced by charge injection and heating
Beilstein J. Nanotechnol. 2019, 10, 840–847, doi:10.3762/bjnano.10.84
- superhydrophobicity and superhydrophilicity has attracted widespread interest because of its important applications. In this work, we propose a reversible superhydrophobic–superhydrophilic conversion induced by charge injection and heating. Different from the conventional electrowetting phenomenon caused by the
- accumulation of solid–liquid interfacial charges, we discovered a phenomenon where charge injection and accumulation at the solid surface results in a sharp increase in wettability. The wettability of a sprayed SiO2 nanoparticle coating on a glass slide was shown to change from superhydrophobic to
- superhydrophilic by charge injection and heating, and the superhydrophobicity was restored by heating, verifying a reversible superhydrophobic–superhydrophilic conversion. The influence of voltage, temperature, and time on the coating wettability and its durability under reversible conversion have been studied
Ultrathin hydrophobic films based on the metal organic framework UiO-66-COOH(Zr)
Beilstein J. Nanotechnol. 2019, 10, 654–665, doi:10.3762/bjnano.10.65
- superhydrophobic materials [34]. The use of different strategies to modify the MOF surface in order to enhance its water stability has been reported in the last years. This was necessary as several MOFs show poor stability in water-containing environments that hinder their use in many real-world applications [34
- ][35]. Superhydrophobic MOFs could be of interest for a great variety of technological applications, including coatings, paints and fabrics [36]. Moreover, it has been shown [37] that these materials could be used as catalysts and in gas separation under humid conditions. In this contribution, mixed
A new bioinspired method for pressure and flow sensing based on the underwater air-retaining surface of the backswimmer Notonecta
Beilstein J. Nanotechnol. 2018, 9, 3039–3047, doi:10.3762/bjnano.9.282
- . Keywords: mechanoreceptor; Notonecta sensor; pressure sensor; Salvinia effect; superhydrophobic surfaces; Introduction The surfaces of animals and plants are interfaces between the organisms and the environment. Since animals and plants inhabit many different environments, it is not surprising that over
- adhesive pads [6] or the structural colors of Morpho menelaus [7]. Superhydrophobic surfaces are also important in the above context. Several plants and animals, which can maintain stable air layers while submerged (Salvinia effect [8]), have been analyzed. Especially the floating ferns of the genus
- detaching from the surface of N. glauca. The deformation of the droplet indicates adhesion between the droplet and the pin-setae. This suggests that the pin-setae penetrate the air–water interface and become wet. b) Water droplet lying on the club-setae of the superhydrophobic surface of N. glauca. c
Biomimetic surface structures in steel fabricated with femtosecond laser pulses: influence of laser rescanning on morphology and wettability
Beilstein J. Nanotechnol. 2018, 9, 2802–2812, doi:10.3762/bjnano.9.262
- superhydrophobic states. Results and Discussion Ripples, grooves and spikes formed by single laser scanning The formation of LIPSSs occurs when a certain number of laser pulses has accumulated in a given area in a single laser scan. For metals and semiconductors, three well-differentiated structures, ripples
- ° and 150°, the surface is considered hydrophobic. In our experiments, more than half the fabricated surfaces present this wetting behavior, changing from 92 ± 2° (1 J/cm2, 1 scan) to 136 ± 6° (0.2 J/cm2, 1 scan). Surfaces that present CAs higher than 150° are considered superhydrophobic. In our case
- reduction capabilities. Characterization of the wettability of the structures revealed that a broad range of different wetting behaviors could be accessed with this approach, ranging from hydrophilic over hydrophobic to superhydrophobic states, with practically the same fabrication time. It is found that
Synthesis of carbon nanowalls from a single-source metal-organic precursor
Beilstein J. Nanotechnol. 2018, 9, 1895–1905, doi:10.3762/bjnano.9.181
- batteries, electrochemical sensors or fuel cells [3][9][10][11][12][13][14][15]. Due to the high aspect ratio and the sharp top edges of the CNWs, a possible application could also be seen as electron field emitters [16]. Depending on the chosen deposition parameters, CNWs can have superhydrophobic or
Review on nanoparticles and nanostructured materials: history, sources, toxicity and regulations
Beilstein J. Nanotechnol. 2018, 9, 1050–1074, doi:10.3762/bjnano.9.98
- allows them to float on water without sinking [194][195]. Based on these reports, many artificial superhydrophobic materials with self-cleaning ability have been manufactured [196] through electrodeposition, photolithography and colloidal systems [197][198][199] with unique morphology and roughness [200
- ][201]. These superhydrophobic materials were useful in applications such as water treatment [202][203], wettability switchers [204][205], smart actuators [206], transparent coatings and electrodes [207][208][209]. Nanoparticles and nanostructures in insects Insect wing membranes are comprised of
- ][225][226] and are not considered as superhydrophobic. Conversely, a WCA greater than 150° was exhibited by the wing of the grasshopper (Acrida cinerea cinerea), dragonfly (Hemicordulia tau) and butterfly species (Papilio xuthus) over their surface. The literature also show that species with
Bioinspired self-healing materials: lessons from nature
Beilstein J. Nanotechnol. 2018, 9, 907–935, doi:10.3762/bjnano.9.85
- superhydrophobic functionality of the surface. In doing so, the rolling drops pick up or absorb particulates and dirt, cleaning the leaf. The superhydrophobic behavior is caused by a combination of hierarchical surface roughness at the nanometer and microscale combined with an epicuticular wax coating [32]. The
- leaf, the combination of hierarchical morphology and a wax coating makes the surface superhydrophobic and self-cleaning by causing water drops to roll off, rather than slide. Active abscission or shedding dead tissue – A key part of a plant’s ability to survive and replicate is through its ability to
Kinetics of solvent supported tubule formation of Lotus (Nelumbo nucifera) wax on highly oriented pyrolytic graphite (HOPG) investigated by atomic force microscopy
Beilstein J. Nanotechnol. 2018, 9, 468–481, doi:10.3762/bjnano.9.45
- ; crystallization; epicuticular wax; Lotus; Nelumbo nucifera; nonacosanol tubules; self-assembly; superhydrophobic; Introduction The plant cuticle, a cutin matrix embedded and covered by waxes provides a multitasking interface between plant and environment [1]. These waxes are either reside within the cutin layer
- . We demonstrate how these different factors affect the tubule growth, in order to gain greater insight into those factors that can affect the tubule growth and which can subsequently be used to manipulate these wax structures on HOPG, e.g., in order to model specific superhydrophobic surfaces
BN/Ag hybrid nanomaterials with petal-like surfaces as catalysts and antibacterial agents
Beilstein J. Nanotechnol. 2018, 9, 250–261, doi:10.3762/bjnano.9.27
- explains their rich functionality in reinforcement of ultralight metals and ceramics, improvement of thermal conductivity and mechanical strength of diverse polymers, production of transparent superhydrophobic films, and quantum electronic and photonic devices [1][2][3][4]. BN nanomaterials have also been
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