All-organic superhydrophobic coatings with mechanochemical robustness and liquid impalement resistance

Peng, Chaoyi; Chen, Zhuyang; Tiwari, Manish K.

doi:10.1038/s41563-018-0044-2

Cited by 632 publications

(460 citation statements)

References 35 publications

Supporting

Mentioning

449

Contrasting

Unclassified

Order By: Relevance

“…1,2 This has served as a driver to research into icephobic surfaces, which can passively prevent ice accumulation by different pathways. Through rational surface micro/nanotexturing of hydrophobic materials, one can fabricate superhydrophobic surfaces [3][4][5][6][7] that can shed supercooled water before it freezes due to high droplet mobility, delay freezing 8,9 or reduce ice adhesion. [10][11][12][13] Previous work also investigated fundamental freezing phenomena highlighting the critical role of environmental conditions on the freezing outcome.…”

mentioning

confidence: 99%

Cascade Freezing of Supercooled Water Droplet Collectives

et al. 2018

View full text Add to dashboard Cite

Surface icing affects the safety and performance of numerous processes in technology.Previous studies mostly investigated freezing of individual droplets. The interaction among multiple droplets during freezing is investigated less, especially on nanotextured icephobic surfaces, despite its practical importance as water droplets never appear in isolation, but in groups. Here we show that freezing of a supercooled droplet leads to spontaneous self-heating and induces strong vaporization. The resulting, rapidly propagating vapor front causes immediate cascading freezing of neighboring supercooled droplets upon reaching them. We put forth the explanation that, as the vapor approaches cold neighboring droplets, it can lead to local supersaturation and formation of airborne microscopic ice crystals, which act as freezing nucleation sites. The sequential triggering and propagation of this mechanism results in the rapid freezing of an entire droplet ensemble resulting in ice coverage of the nanotextured surface. Although cascade freezing is observed in a low-pressure environment, it introduces an unexpected pathway of freezing propagation that can be crucial for the performance of rationally designed icephobic surfaces.

show abstract

mentioning

confidence: 99%

Cascade Freezing of Supercooled Water Droplet Collectives

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Water impalement was observed after 12 mL of water were emptied on the surface. Although many robust superhydrophobic surfaces have been reported in the literature (mostly in the form of composite coatings) with considerable greater performance compared to our material, no such durability levels have been achieved with a pillar‐patterned material composed by fully degradable and natural organic components like the one presented here.…”

Section: Resultsmentioning

confidence: 79%

Engineering Fully Organic and Biodegradable Superhydrophobic Materials

Milionis

Sharma

Hopf

et al. 2018

Adv Materials Inter

View full text Add to dashboard Cite

superhydrophobic materials have been reported. [12] However, most of these materials make use of petroleum derivatives and fluorinated compounds, [13] as well as textured inorganic materials, [14] which serve as substrates for surface chemical functionalization. These materials are not inherently biodegradable and thus pose a challenge in terms of environmental impact and recyclability. Especially longchain fluorinated compounds, which are used often to obtain liquid repellency, are difficult to degrade and tend to bioaccumulate. [15,16] Furthermore, even if these substances degrade after a prolonged period, some of their by-products are known to be toxic, such as perfluorooctanoic acid [17] and perfluorooctanesulfonate. [18] Recent studies have reported the use of more sustainable methods and materials to obtain the self-cleaning effect. These include the use of biodegradable polymers and natural materials, [19] waterborne spray approaches, [20] alcoholic solvent environment, [21] silicone-based biocompatible materials, [22] reactive polymeric materials, [23] fluorine-free substances, [24][25][26] cellulose-based, [27] and natural wax-based material compositions. [28,29] The use of the latter two materials (cellulose and wax) is inspired from the fact that they are the main constituents of a broad selection of plants, including the well-known Lotus leaf. [30] Cellulose is the material that mainly constitutes the substrate and is responsible for the leaf's mechanical properties and microroughness (the latter in the form of macropapillae) in a wide range of plants. On the other hand, the wax nanocrystals cover the microtopography and are responsible for the superhydrophobicity, bothThe development of fully organic (cellulose/wax based), biodegradable, and hierarchically textured superhydrophobic material, inspired by natural, selfcleaning plants, like the Lotus leaf is reported. The developed material can reproduce in a controllable and artificial manner the chemical composition and material properties of these natural surfaces. At the same time, the fabrication protocol described here enables realization of properties beyond the ones found in the natural leaves, by allowing facile tuning of the topographical and mechanical properties. The surface topography consists of a micropillar structure assembly with, to the best of the authors' knowledge, the highest to date reported aspect ratio (7.6) for cellulose materials. Additionally, control and tunability of the material's mechanical properties are also demonstrated, which is rendered softer (down to 227 MPa Young's modulus from 997 MPa base value) by adding glycerol as a natural plasticizer. Finally, the self-cleaning properties are demonstrated and the biodegradability of the material is evaluated in a period of ≈3 months, which confirms full biodegradation. Additionally, water drop and jet impact, and folding tests demonstrate that the material can reasonably sustain its wettability properties. Such a truly bioinspired and biodegradable material system could fin...

show abstract

“…will be transformed into elastic potential energy of the microsized structure. In this work, 3D profile measurement reveals that the average length of the individual microsized structure is ≈32 µm which is much higher than that of the normal hierarchical rough structure for constructing superhydrophobic coatings It is also noting that the coral‐reef‐like structure could greatly improve the flexibility of the microsized structure. Each of the tentacle on the coral‐reef‐like structure could act as an individual cantilever and consequently, every individual coral‐reef‐like structure could be compared to a laminated cantilever beam such as the leaf spring used on vehicles .…”

mentioning

confidence: 79%

“…Many efforts including building micro/nanoscale surface textures with self‐similar manner, designing smart self‐healable/recoverable surface architectures and making the texture either stiffer with ceramics or more complaint with polymers have been done to enhance the mechanical robustness of the artificial superhydrophobic surfaces. According to these criteria, mechanically robust superhydrophobic coatings have been realized through either applying adhesive to strengthen the adhesion of the fluorinated nanosized oxide particles painting or painting and curing multifluorinated epoxy resin on various materials . Generally, it is believed that surface textures made of hydrophobic bulk materials should be avoided since as long as the surface is broken, newly exposed hydrophilic areas will act as water pinning sites .…”

mentioning

confidence: 99%

Bioinspired Mechanically Robust Metal‐Based Water Repellent Surface Enabled by Scalable Construction of a Flexible Coral‐Reef‐Like Architecture

Luo

2019

Small

View full text Add to dashboard Cite

Mechanical robustness is a central concern for moving artificial superhydrophobic surfaces to application practices. It is believed that bulk hydrophilic materials cannot be use to construct micro/nanoarchitectures for superhydrophobicity since abrasion‐induced exposure of hydrophilic surfaces leads to remarkable degradation of water repellency. To address this challenge, the robust mechanical durability of a superhydrophobic surface with metal (hydrophilic) textures, through scalable construction of a flexible coral‐reef‐like hierarchical architecture on various substrates including metals, glasses, and ceramics, is demonstrated. Discontinuous coral‐reef‐like Cu architecture is built by solid‐state spraying commercial electrolytic Cu particles (15–65 µm) at supersonic particle velocities. Subsequent flame oxidation is applied to introduce a porous hard surface oxide layer. Owing to the unique combination of the flexible coral‐reef‐like architecture and self‐similar manner of the fluorinated hard oxide surface layer, the coating surface retains its water repellency with an extremely low roll‐off angle (<2°) after cyclic sand‐paper abrasion, mechanical bending, sand‐grit erosion, knife‐scratching, and heavy loading of simulated acid rain droplets. Strong adhesion to glass, ceramics, and metals up to 34 MPa can be achieved without using adhesive. The results show that the present superhydrophobic coating can have wide outdoor applications for self‐cleaning and corrosion protection of metal parts.

show abstract

All-organic superhydrophobic coatings with mechanochemical robustness and liquid impalement resistance

Cited by 632 publications

References 35 publications

Cascade Freezing of Supercooled Water Droplet Collectives

Cascade Freezing of Supercooled Water Droplet Collectives

Engineering Fully Organic and Biodegradable Superhydrophobic Materials

Bioinspired Mechanically Robust Metal‐Based Water Repellent Surface Enabled by Scalable Construction of a Flexible Coral‐Reef‐Like Architecture

Contact Info

Product

Resources

About