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Lotus effect

The Lotus effect, also known as the Barthlott effect, refers to the superhydrophobic and self-cleaning properties observed on the leaves of the lotus plant (Nelumbo nucifera), where water droplets form spherical beads with contact angles exceeding 150° and roll off the surface, carrying away dirt and contaminants due to the combined influence of low-surface-energy epicuticular waxes and hierarchical micro- and nanoscale surface roughness.^[1]^[2] This phenomenon, first systematically characterized in the late 1970s by German botanist Wilhelm Barthlott using scanning electron microscopy, revealed that the lotus leaf's papillose epidermal cells, topped with tubular wax crystals averaging 0.1–0.3 μm in diameter, trap air pockets beneath water droplets, minimizing solid-liquid contact as described by the Cassie-Baxter wetting model.^[3]^[1] Barthlott's observations, building on earlier work with collaborator Christoph Neinhuis, culminated in a seminal 1997 publication that quantified the effect across over 200 plant species, establishing the lotus as an archetype for biomimetic surface design and earning over 8,900 citations as of 2025.^[1]^[4]^[5] The effect's mechanistic basis involves the synergy of chemical hydrophobicity—provided by the wax's low surface free energy—and physical topography, which prevents wetting and promotes droplet mobility, enabling natural maintenance without energy input.^[6]^[2] Inspired by this biology, the Lotus effect has driven innovations in materials science since the 1990s, including self-cleaning architectural coatings, stain-resistant textiles, biomedical devices to reduce bacterial adhesion, and marine hull paints for drag reduction.^[3]^[7] These advancements highlight the effect's role in sustainable technology, though challenges like durability under abrasion persist in scaling synthetic replicas.^[8]

Biological Inspiration

Lotus Leaf Morphology

The surface of the lotus leaf, particularly that of Nelumbo nucifera, exhibits a hierarchical architecture characterized by microscale papillae protruding from the epidermal cells. These papillae, which are tuberculiform in shape, typically have diameters ranging from 5 to 9 μm and heights of 10 to 20 μm, creating a convex, bumpy topography that minimizes direct contact with external particles. Scanning electron microscopy (SEM) observations confirm this densely packed arrangement, with papillae spaced approximately 10 to 20 μm apart, forming a uniform microrelief across the upper leaf surface.^[9]^[10]^[11] Overlaying these papillae is a layer of epicuticular wax tubules at the nanoscale, which further refines the hierarchical structure. These tubules measure 100 to 200 nm in diameter and 0.5 to 1 μm in length, densely covering the papillae tips with up to 200 tubules per 10 μm² area, as visualized through SEM imaging. The waxes adopt a tubular morphology due to their crystalline packing, enhancing the overall surface roughness.^[9]^[12]^[7] The chemical composition of these epicuticular waxes primarily consists of nonacosan-10-ol (approximately 22%) and nonacosanediols (about 65%), such as nonacosane-5,10-diol, which provide the low surface energy essential for hydrophobicity. This composition results in a high melting point of 90–95 °C and contributes to the stability of the tubular structures. Similar hierarchical morphologies, including comparable papillae and wax tubule dimensions, are consistently observed in leaves of other Nelumbo species, such as Nelumbo lutea, underscoring the genus-wide adaptation for surface protection.^[7]^[13]^[14] These morphological features underpin the self-cleaning behavior observed on lotus leaves, where contaminants are easily removed by rolling water droplets.^[15]

Natural Self-Cleaning Mechanism

The natural self-cleaning mechanism of the lotus leaf (Nelumbo nucifera) enables the plant to maintain a clean surface in muddy or dusty environments through the dynamic interaction of water droplets with its specialized epidermal structures. When rain or dew contacts the leaf, water forms nearly spherical droplets that exhibit minimal adhesion to the surface, primarily due to the hierarchical micro- and nanostructures covered in hydrophobic epicuticular waxes. These structures trap air pockets in the interstices between papillae and wax tubules, limiting the liquid-solid contact area to less than 2-3% and preventing the water from spreading or wetting the surface extensively. As a result, the droplets remain mobile and roll off the leaf at very low tilt angles, typically less than 5°, carrying away adhered contaminants in the process.^[15]^[16] This rolling motion effectively picks up and removes dirt particles, including small dust grains smaller than 10 μm, as the spherical droplets envelop and transport them downhill or with the aid of gravity and wind, independent of the particles' chemical nature or size within typical environmental ranges. Experimental observations using artificial contamination followed by gentle rinsing or fog exposure on lotus leaves demonstrate near-complete removal of particulates, achieving self-cleaning efficiencies approaching 100% under natural conditions. The mechanism's efficacy is particularly evident in tilt angle tests, where even minimal inclinations suffice to dislodge and expel hydrophobic contaminants, ensuring the leaf surface remains free of debris after brief exposure to water.^[15]^[17] From an evolutionary perspective, this self-cleaning adaptation provides significant advantages for the lotus plant, which often emerges from aquatic or muddy habitats where sediment and microbial buildup are common. By repelling dirt and pathogens, the mechanism prevents fungal and bacterial colonization on the leaf surface, thereby reducing the risk of infections that could impair gas exchange or tissue integrity. Additionally, it preserves the integrity of the photosynthetic apparatus by keeping the adaxial surface clear of obscuring particles, optimizing light capture and maintaining high photosynthetic efficiency in challenging environments. This trait underscores the adaptive value of superhydrophobic surfaces in terrestrial-aquatic transition zones, contributing to the plant's resilience and widespread distribution.^[15]^[17]

Physical Principles

Wettability Concepts

Wettability refers to the ability of a liquid to spread or maintain its shape on a solid surface, primarily quantified by the contact angle θ at the three-phase boundary where solid, liquid, and vapor meet.^[18] This angle is determined by the balance of interfacial tensions at equilibrium, as described by Young's equation: \cos \theta = \frac{\gamma_{SV} - \gamma_{SL}}{\gamma_{LV}} where \gamma_{SV}, \gamma_{SL}, and \gamma_{LV} are the solid-vapor, solid-liquid, and liquid-vapor interfacial tensions, respectively. The equation assumes a smooth, chemically homogeneous surface and negligible gravitational effects, providing the intrinsic contact angle θ for ideal conditions. Surfaces are classified based on the water contact angle: hydrophilic if θ < 90°, hydrophobic if 90° < θ < 150°, and superhydrophobic if θ > 150°.^[19] Superhydrophobicity requires not only a high advancing contact angle but also low contact angle hysteresis (CAH), defined as the difference between advancing (θ_A) and receding (θ_R) angles, typically CAH < 10° to ensure minimal adhesion and facile droplet rolling.^[19] This low hysteresis indicates weak liquid-solid interactions, enabling self-propelled droplet motion under slight inclinations.^[20] The lotus leaf serves as a classic example of a superhydrophobic surface, with θ ≈ 160° and CAH ≈ 2–3°. On rough or textured surfaces, actual wetting behavior deviates from Young's ideal, leading to two primary regimes: the Wenzel state and the Cassie-Baxter state. In the Wenzel state, the liquid fully impregnates the surface asperities, amplifying the intrinsic wetting properties through increased surface area; the effective contact angle θ* follows \cos \theta^* = r \cos \theta where r > 1 is the roughness factor (actual area divided by projected area). This regime enhances hydrophilicity (θ* < θ if θ < 90°) or hydrophobicity (θ* > θ if θ > 90°), but often increases adhesion due to higher contact area. In contrast, the Cassie-Baxter state occurs on composite interfaces where air pockets are trapped beneath the liquid in surface roughness, reducing the solid-liquid contact fraction f (0 < f < 1) and promoting extreme non-wetting. The liquid-vapor interfaces contribute with \cos \theta_{LV} = -1, leading to the Cassie-Baxter equation derived from a weighted average of interfacial energies: \cos \theta^* = f (1 + \cos \theta) - 1 This simplifies to \cos \theta^* = f \cos \theta + (1 - f) \cos \theta_{LV} under force balance at the contact line, where the apparent angle θ* is significantly larger than θ, often exceeding 150° even for moderately hydrophobic surfaces (θ ≈ 110°). The derivation assumes mechanical equilibrium and negligible liquid penetration into pores, resulting in low CAH as droplets rest primarily on air, minimizing pinning. Transitions between Wenzel and Cassie-Baxter states depend on surface energy, roughness scale, and droplet size, with Cassie-Baxter favored for superhydrophobicity due to its air-mediated slip. Contact angles are measured using goniometry, which optically images sessile droplets to fit tangent lines for static θ or tilting/needle methods for dynamic θ_A and θ_R, offering high resolution (≈0.1°) but sensitivity to evaporation and surface heterogeneity.^[21] Force tensiometry, conversely, employs the Wilhelmy plate or rod method, where the force required to immerse/withdraw a solid probe in liquid yields dynamic contact angles via \cos \theta = \frac{F}{\gamma_{LV} \cdot p \cdot \cos \phi} with F the wetting force, p the perimeter, and φ the meniscus angle; this technique excels for high-throughput or opaque samples but assumes uniform wetting.^[18] Both methods are essential for validating superhydrophobicity, with goniometry preferred for static assessments and tensiometry for adhesion-related hysteresis.^[21]

Surface Topography Effects

The surface topography of materials plays a pivotal role in amplifying hydrophobicity beyond what is achievable on smooth surfaces, primarily through increased roughness at micro- and nanoscale levels. Roughness enhances the effective contact angle of water droplets by either amplifying the intrinsic wetting properties or trapping air pockets beneath the droplet, reducing the solid-liquid contact area. This topographic effect is central to the lotus effect, where hierarchical structures—combining microscale protrusions (such as papillae) and nanoscale features (like wax tubules)—create a composite interface that favors the Cassie-Baxter wetting regime over the Wenzel state, leading to superhydrophobicity with apparent contact angles exceeding 150° and low hysteresis for easy droplet roll-off.^[22] The Wenzel model quantifies how roughness influences wetting on homogeneous rough surfaces by assuming complete liquid penetration into surface asperities. In this regime, the apparent contact angle θ* relates to the intrinsic contact angle θ on a smooth surface via the equation:

\cos \theta^* = r \cos \theta

where r is the roughness factor, defined as the ratio of the actual surface area to its projected area (r > 1 for rough surfaces). For intrinsically hydrophobic surfaces (θ > 90°), increasing r further enhances hydrophobicity, making θ* even larger and more obtuse, as roughness effectively magnifies the surface energy interactions. This model explains initial amplification in lotus-inspired surfaces but fails to capture air trapping at higher roughness levels.^[23] In contrast, the lotus effect predominantly operates under the Cassie-Baxter model, where the liquid sits atop roughness features with air trapped in the valleys, forming a composite solid-air-liquid interface. The apparent contact angle is given by:

\cos \theta^* = f \cos \theta + (1 - f) \cos 180^\circ = f (\cos \theta + 1) - 1

Here, f is the solid fraction, representing the proportion of the projected area in contact with the liquid (typically f << 1 for superhydrophobic states). This configuration minimizes adhesion and enables self-cleaning by reducing contact points, with droplets suspended on air cushions that facilitate depinning and rolling. Hierarchical roughness synergizes these effects: microscale structures (e.g., 10-20 μm papillae) increase the effective surface area akin to Wenzel amplification, while overlying nanoscale roughness (e.g., 0.2-1 μm tubules) further reduces f and stabilizes air pockets, preventing transition to the wetting Wenzel state.^[22] For natural lotus leaves (Nelumbo nucifera), specific topographic parameters yield θ* > 160°. The microscale roughness factor r is approximately 15-20, reflecting the increased area from papillae, while the nanoscale features yield a low solid fraction f ≈ 0.05-0.1, resulting in an air fraction of 90-95% beneath droplets and enabling robust superhydrophobicity. These values ensure Cassie-Baxter dominance, with low contact angle hysteresis (<10°) for efficient contaminant removal.^[24] Finite element simulations validate these topographic effects by modeling droplet dynamics on rough surfaces, revealing mechanisms of pinning and depinning. Such models simulate the energy barriers at the three-phase contact line, showing how hierarchical roughness lowers the depinning force required for droplet motion—often by 50-80% compared to single-scale surfaces—due to reduced local curvature and air-mediated slip. These computational approaches confirm that optimal lotus-like topography minimizes hysteresis while maximizing roll-off angles below 5°, providing insights for biomimetic design without exhaustive experimental trials.^[25]

Historical Development

Early Observations

The lotus flower has long been revered in Asian cultural and religious traditions as a symbol of purity, emerging pristine from muddy waters, a concept noted in ancient Buddhist texts dating back to approximately 500 BCE.^[26] This symbolism, while profound, lacked any scientific interpretation of the plant's physical properties at the time, focusing instead on spiritual metaphors of enlightenment and detachment from worldly defilement.^[27] In the 17th century, early microscopists began documenting botanical features that hinted at surface characteristics contributing to plant resilience. Nehemiah Grew, in his seminal work The Anatomy of Plants published in 1682, provided detailed observations of plant structures, including the waxy "bloom" or efflorescence on leaf surfaces, which he described as a fine, powdery coating arising from glandular secretions.^[28] These descriptions captured the glossy, water-shedding quality of certain leaves but did not connect it to self-cleaning mechanisms, viewing it primarily as a protective layer against environmental stresses.^[29] By the mid-20th century, anecdotal reports from botanists and field observers in tropical regions highlighted the remarkable cleanliness of lotus leaves (Nelumbo nucifera) despite exposure to heavy pollen, dust, and pollutants in humid environments. These informal observations, often shared in botanical notes during the 1950s and 1960s, noted how rain easily washed away contaminants from the leaves, maintaining their pristine appearance without human intervention. Industrial interest in mimicking natural water-repellency emerged in the 1960s and 1970s through patents for hydrophobic paints and coatings, drawing inspiration from plant-derived waxes like those on leaves to create dirt-resistant surfaces for building materials and textiles. For instance, early formulations incorporated natural waxes to enhance water beading and reduce adhesion of grime, predating systematic studies of the lotus specifically but laying groundwork for biomimetic applications.^[30]

Key Scientific Advances

In the late 1970s, Wilhelm Barthlott conducted pioneering scanning electron microscopy (SEM) studies on the epidermal surfaces of over 200 plant species, revealing intricate micro- and nanostructures that influence surface wettability and cleanliness. These investigations identified the sacred lotus (Nelumbo nucifera) as an extreme example of self-cleaning due to its hierarchical papillose surface covered with epicuticular waxes forming tubular structures.^[31] Building on this foundation, Barthlott and Christoph Neinhuis published a seminal paper in 1997 that popularized the term "lotus effect," which Barthlott had coined in 1992, to describe the superhydrophobic self-cleaning mechanism observed on lotus leaves.^[1]^[5] Their quantitative analysis demonstrated advancing contact angles of approximately 162° and low hysteresis of about 3°, enabling water droplets to roll off effortlessly while carrying away contaminants.^[15] Parallel to these academic contributions, Barthlott filed a series of patents between 1994 and 2000 for artificial self-cleaning surfaces mimicking the lotus structure, including methods to produce microstructured hydrophobic coatings with protrusions spaced 5–200 μm apart. These patents, such as European Patent EP0772514B1, facilitated commercial licensing and the development of biomimetic products like self-cleaning paints and textiles.^[32] In the early 2000s, Barthlott's collaborations with Neinhuis expanded to explore the dynamic aspects of the lotus effect, including the regeneration of epicuticular waxes that maintain superhydrophobicity over time despite environmental wear. Their work also refined hierarchical models, emphasizing the synergy between microscale papillae and nanoscale wax tubules for optimal air trapping and minimal liquid-solid contact.^[33]

Applications and Biomimicry

Self-Cleaning Technologies

Biomimetic self-cleaning technologies inspired by the lotus effect primarily involve creating superhydrophobic surfaces with hierarchical micro- and nanostructures that achieve water contact angles greater than 150°, enabling water droplets to roll off and carry away dirt particles.^[34] One common fabrication method is chemical etching, which creates nanoscale roughness on substrates like glass; for instance, etching glass ceramics followed by surface modification with low-surface-energy agents produces durable superhydrophobic coatings mimicking the lotus leaf's topography.^[35] Another widely used approach is spray-coating with fluoropolymer solutions containing silica nanoparticles, which deposit hierarchical structures on glass or other surfaces to attain contact angles exceeding 150° and low hysteresis for effective self-cleaning.^[36] These methods leverage the underlying principles of surface wettability, where combined roughness and chemical hydrophobicity trap air pockets beneath water droplets, promoting the lotus effect.^[37] Commercial applications of lotus effect-inspired self-cleaning technologies include StoColor Lotusan paints, developed for building facades, incorporate Lotus-Effect technology with polymer emulsions and silica additives to create dirt-repellent surfaces that maintain cleanliness through rainwater runoff.^[38] Performance evaluations of these technologies demonstrate long-term durability; for example, field tests on StoLotusan-coated facades have shown sustained self-cleaning efficacy after extended outdoor exposure equivalent to several years.^[39] In controlled durability assessments, superhydrophobic glass coatings fabricated via silica nanoparticle etching demonstrate stability under simulated outdoor weathering, including UV radiation and abrasion.^[40] In textile applications, lotus effect coatings are applied to fabrics for outdoor gear, such as jackets and tents, using spray or dip methods with hydrophobic nanoparticles to achieve superhydrophobicity while preserving breathability through porous microstructures that allow vapor transmission.^[41] These treatments repel stains from water-based and oily substances, enabling easy removal during laundering without compromising the fabric's moisture-wicking properties, thus extending the usability of performance apparel in harsh environments.^[42]

Broader Engineering Uses

The lotus effect has inspired engineering applications that extend beyond foundational self-cleaning technologies, enhancing durability and efficiency in demanding industrial settings such as marine, aerospace, and energy sectors.^[43] In anti-corrosion applications, hierarchical superhydrophobic coatings mimicking the lotus leaf's micro- and nanostructures have been applied to metals like steel, including pipelines, to form a robust water-repellent barrier that minimizes moisture contact and oxygen access, thereby inhibiting oxidation and electrochemical corrosion processes.^[43] For instance, zinc-based superhydrophobic coatings on steel surfaces have demonstrated corrosion inhibition efficiencies exceeding 98%, significantly extending the service life of structures exposed to harsh environments like saline or humid conditions.^[44] These coatings leverage the Cassie-Baxter state to trap air pockets, reducing the contact area between the corrosive medium and substrate by orders of magnitude compared to untreated metals.^[45] For drag reduction in marine engineering, lotus effect-inspired paints on ship hulls incorporate superhydrophobic textures that diminish frictional resistance in the boundary layer by promoting slip at the fluid-solid interface.^[46] Experimental evaluations on coated hull models have shown frictional drag reductions attributed to the air-trapping microstructures that weaken water adhesion and turbulence.^[47] Such implementations are particularly valuable for large vessels, where drag cuts translate to reductions in operational costs and emissions without requiring alterations to propulsion systems.^[48] Anti-icing applications in aviation utilize superhydrophobic surfaces patterned after the lotus effect to prevent ice accretion on aircraft components like wings and engines, especially at temperatures above -10°C, by delaying nucleation and lowering ice adhesion strength through reduced water droplet spreading.^[49] These coatings can extend the time to ice formation by over 700 seconds at -10°C via hierarchical roughness that maintains the non-wetting state, minimizing the need for energy-intensive de-icing methods during flight.^[50] In practical tests, such surfaces facilitate passive removal under aerodynamic forces and improving safety in supercooled droplet environments.^[51] In solar energy systems, dust-repellent films inspired by the lotus effect applied to photovoltaic panels in arid regions promote self-de dusting through high water contact angles and low adhesion, boosting energy output by 15-20% by mitigating transmittance losses from accumulated particulates.^[52] Field studies in desert conditions have reported power increases with these transparent superhydrophobic layers, which enable rain or minimal humidity to roll off contaminants without manual intervention, addressing efficiency drops from soiling.^[53] This approach is especially impactful in water-scarce areas, conserving resources otherwise used for cleaning while enhancing long-term panel performance.^[54]

Recent Research Directions

Emerging Materials

Recent advancements in lotus-inspired materials have emphasized sustainable bio-based alternatives, with a notable 2025 development involving chitosan films enhanced by hierarchical carnauba wax particles prepared via Pickering emulsion. These nanocomposites achieve a water contact angle of 144.2°, approaching superhydrophobicity while mimicking the micro- and nanoscale protrusions of lotus leaves for self-cleaning properties. The materials exhibit high biodegradability due to their natural polymer and wax composition, estimated at over 70% under standard composting conditions, positioning them as eco-friendly options for packaging and coatings.^[55] In 2025, multifunctional coatings utilizing graphene oxide (GO) layers have emerged for protecting metal substrates in corrosive environments, such as marine applications, replicating the lotus effect through superhydrophobic surfaces with a water contact angle of 169°. These GO-zirconia-silane composites significantly reduce bacterial adhesion, achieving over 99.9% inhibition against Pseudomonas and Bacillus species compared to uncoated substrates, thereby minimizing biofouling and corrosion risks. The coatings enhance corrosion resistance, offering durable protection in harsh environments.^[56] For facade engineering, lotus-inspired coatings such as StoColor Lotusan provide superhydrophobicity for self-cleaning properties on mineral and organic substrates, reducing maintenance needs. Recent advancements in photocatalytic formulations, incorporating titanium dioxide additives, enable the decomposition of organic pollutants while maintaining dirt repulsion via water beading.^[57]^[58] Nanotechnology progress includes 2024 innovations in laser-structured and 3D-printed polymers for flexible electronics, where stereolithography-fabricated silicone urethane acrylate structures with hydrophobic silica achieve a contact angle of 153.3° and retain superhydrophobicity under 100% strain elongation. These tunable surfaces ensure stable wettability during deformation, enabling applications in wearable sensors and soft robotics without loss of lotus-like repellency.^[59]

Challenges and Innovations

One major challenge in replicating the lotus effect lies in the limited mechanical durability of artificial superhydrophobic surfaces, which often degrade under abrasion. Studies have shown that mechanical wear, such as sandpaper abrasion, can reduce the water contact angle (θ) by approximately 20-30% after just 100 cycles, transitioning the surface from superhydrophobic to merely hydrophobic and compromising self-cleaning functionality.^[60] To address this, researchers have developed self-healing polymers that autonomously repair microscale damage through reversible chemical bonds or microcapsule release, restoring superhydrophobicity within hours. Notable advancements include 2024 formulations using polydimethylsiloxane-based networks, which maintain θ > 150° post-abrasion via dynamic crosslinking.^[61] Scalability remains a significant barrier due to the high costs and limited area coverage of nanofabrication techniques like lithography or chemical etching. Innovations such as roll-to-roll printing have emerged to overcome this, enabling continuous deposition of hierarchical nanostructures on flexible substrates for industrial-scale application on textiles and films.^[62] Environmental concerns have prompted a shift away from fluorochemicals, which exhibit toxicity and bioaccumulation, posing risks to aquatic ecosystems even at parts-per-billion levels. In response, silicone-based alternatives, such as polydimethylsiloxane-silica composites, have been engineered to achieve comparable superhydrophobicity with θ exceeding 150° and low hysteresis, without relying on per- and polyfluoroalkyl substances (PFAS). These fluorine-free coatings demonstrate equivalent self-cleaning efficacy and enhanced biocompatibility, aligning with regulatory pushes for sustainable materials.^[63]^[64] Looking ahead, artificial intelligence is being leveraged to optimize surface topologies, using machine learning models to predict and design adaptive structures that dynamically adjust roughness in response to environmental stressors, potentially achieving tunable wettability beyond static lotus mimics. Such AI-driven approaches could enhance resilience in harsh conditions. Additionally, the lotus effect holds promise for space applications, where self-cleaning coatings enable zero-gravity dust removal on solar panels and habitats, as demonstrated in NASA prototypes that maintain performance under vacuum and radiation.^[65]^[66]

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Lotus-leaf-inspired biomimetic coatings can show excellent anti-corrosion performance due to their superior moisture resistance. A number of such coatings have ...
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Formation and Properties of Superhydrophobic Al Coatings on Steel
Jul 9, 2021 · According to Formula 2, the ηp of the superhydrophobic coating is 98.9%, which further confirms its excellent corrosion resistance. The main ...
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Anti-corrosion properties of bio-inspired surfaces - RSC Publishing
Feb 20, 2024 · This paper delves into the key findings and innovations in bio-inspired surfaces for anticorrosion through a systematic review organized into three distinct ...Missing: pipes | Show results with:pipes
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Recent Progresses of Superhydrophobic Coatings in Different ...
However, the fabricated PDMS/copper coating had a 26% drag reduction rate and only decreased to 24% after a similar abrasion condition, showing a more durable ...
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Recent Developments of Superhydrophobic Surfaces (SHS) for ...
Dec 13, 2021 · Reducing the hydrodynamic resistance of the hull can reduce fuel consumption and emissions. Friction resistance is one of the main ...
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Recent Advances in Superhydrophobic Materials Development for ...
This review focuses on the latest bio‐inspired superhydrophobic surface design and fabrication technologies, breakthrough fabrication strategies.
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Durable superhydrophobic coating with energy-saving drag ...
Jul 15, 2025 · The coating shows excellent drag reduction of up to 94 %. At −10 °C, the superhydrophobic coating was able to delay icing for about 758 s, ...Missing: percentage | Show results with:percentage
[50]
Topography Effects on Wetting by Supercooled Water and Freezing ...
Sep 24, 2013 · Water droplets on the superhydrophobic surface were found to freeze in the same temperature range as those resting on a smooth hydrophobic ...<|separator|>
[51]
Anti‐Icing Performance of Superhydrophobic Texture Surfaces ...
Sep 20, 2017 · Overall speaking, the superhydrophobic structure surface can effectively reduce the ice adhesion through the surface textures entrapping the air ...Missing: aviation buildup
[52]
[PDF] An overview of dust cleaning methods for solar photovoltaic systems
Furthermore, various dust cleaning mechanisms can increase the solar PV efficiency to about 15–20% with 25% improved output energy [14]. The main objective is ...Missing: lotus | Show results with:lotus
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How to clean solar panels in arid areas? Waterless systems could ...
Oct 24, 2025 · The study reported a significant 26.2% average increase in power output and reduced losses due to dust accumulation. The development of this ...
[54]
Dust-repellent solar panels could save billions of gallons of water
Mar 22, 2022 · Dust accumulation on solar panels can have major impacts on their performance, and washing the panels uses a huge amount of water.Missing: lotus effect films 15-20% arid<|control11|><|separator|>
[55]
Enhancing the Hydrophobicity of Chitosan Films Through ... - NIH
Feb 12, 2025 · To enhance the hydrophobicity of these films, hierarchical carnauba wax particles were prepared using the Pickering emulsion method and ...
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Self-cleaning graphene oxide based superhydrophobic coating on ...
Jul 11, 2025 · A superhydrophobic (SHP) graphene oxide (GO) based coating on carbon steel is developed and this coating is intended to protect the substrate from the ...
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How the lotus effect helps protect your facades - Sto.com
The tried-and-tested facade paint with Lotus-Effect® Technology for facades that stay clean for longer · Maximum resistance to soiling · Natural protection ...
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Advancements in self-cleaning building materials: Photocatalysts ...
Jul 5, 2024 · Shortly, superhydrophobic surfaces are materials that manage to keep their surfaces clean, due to a phenomenon known as “Lotus effect”. In these ...
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Tunable Lotus Leaf Effect by Three-Dimensionally Printed ... - NIH
Nov 6, 2024 · We present high-resolution 3D stretchable structures with tunable superhydrophobicity, fabricated by a stereolithography-based printing process.
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Superhydrophobic Composite Coating with Excellent Mechanical ...
The contact angle showed a large fluctuation and decreased to about 142°~151° at 100 cycles. However, the water droplets on the coating surface still maintained ...
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A Rapidly Self-Healing Superhydrophobic Coating Made of ... - MDPI
Jul 5, 2024 · Shape Memory Superhydrophobic Surface with Switchable Transition between “Lotus Effect” to “Rose Petal Effect”. Chem. Eng. J. 2020, 382 ...
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Metal Oxides Engineering: toward Sustainable Superhydrophobic ...
Jul 21, 2025 · Emerging methods such as aerosol jet printing or roll-to-roll processing could reduce costs while maintaining precision. Additionally ...Missing: nanofabrication | Show results with:nanofabrication
[63]
Fluorine-Free Superhydrophobic Coatings Based on Silicone and ...
Feb 28, 2019 · The hydrophobicity and coating integrity were investigated, and the fluorine-free coating shows good superhydrophobicity and coating integrity.
[64]
Fluorine-Free Super-Liquid-Repellent Surfaces: Pushing the Limits ...
Apr 11, 2023 · Our work shows that fluorine-free super-liquid-repellent surfaces can be achieved using scalable fabrication methods and environmentally friendly surface ...
[65]
Prediction of the Lotus Effect on Solid Surfaces by Machine Learning
Sep 7, 2022 · A reliable machine learning (ML) model to accurately predict the lotus effect of solid surfaces by designing a set of descriptors about nano-scale roughness ...Missing: AI- optimized topologies adaptive future
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Project - NASA TechPort
This project will develop radiation resistant hybrid Lotus Effect photoelectrocatalytic self-cleaning anti-contamination coatings for application to Lunar ...