•Superamphiphobic fabrics were fabricated by synergistic hydrophobization.•The synergistic hydrophobization lowered the amount of fluorinated compound needed.•The as-obtained fabrics have excellent durability of superamphiphobicity.•The superamphiphobic fabrics show brilliant resistance to blood staining.Superhydrophobic poly(ethylene terephthalate) (PET) fabrics were firstly fabricated by one-pot in situ Stöber reaction of tetraethylorthosilicate (TEOS) and dodecyltrimethoxysilane (DTMS), in which the as-formed silica particles roughened the fiber surfaces and the hydrolyzed dodecyltrimethoxysilane hydrophobized the fabrics. Then the superhydrophobic fabrics were turned superamphiphobic after modification with perfluorodecyltrichlorosilane (PFDTS), with water and oil contact angles higher than 150°. The synergistic hydrophobization of DTMS, PFDTS and PDMS made the roughened fabrics easy to be superamphiphobic using very low concentration of PFDTS. Meanwhile, the as-obtained superamphiphobic fabric showed excellent chemical robustness even after exposure to different chemicals, such as acid, base, and salt. Importantly, the fabrics were durable to 100 cycles of laundries, 1000 cycles of mechanical abrasion as well as long time exposure to UV irradiation without apparently changing the amphiphobicity. Also, the surface of the superamphiphobic fabrics showed excellent blood stain resistance properties.Download high-res image (134KB)Download full-size image

Multifunctional fabrics with excellent water repellency are very useful for practical applications. In this study, poly(ethylene terephthalate) (PET) fabrics were functionalized by introducing carbon nanotubes (CNTs) onto the PET fibers via a facile layer-by-layer electrostatic assembly using poly(dimethyl diallyl ammonium chloride) as a polyelectrolyte, followed by post-treatment with poly(dimethylsiloxane) (PDMS). The obtained fabric surfaces possessed superhydrophobicity, UV blocking properties and electrical conductivity. The hydrophobicity and electrical conductivities of the PET fabrics were systematically tunable by controlling the number of assembly layers. Wettability tests showed that the superhydrophobicity of the modified fabrics was robust to acid/alkaline etching, UV irradiation, long-time laundering and mechanical abrasion. Moreover, electrical conductivity showed no significant change even after repeating water laundering 20 times.

Superhydrophobic fabrics were fabricated by creation of roughening structures through alkali etching of fibers, modification with mercapto silanes and hydrophobization via thiol–ene click chemistry. Alkali etching resulted in nanoscale pits on the fiber surfaces roughening the fabrics with hierarchical structures, and improved the affinity of fibers for mercapto silanes. The click reaction between dodecafluoroheptyl methacrylate and sulfhydryl fibers lowered the surface energy, making the fabrics superhydrophobic with superoleophilicity. The as-obtained superhydrophobic fabrics showed excellent chemical robustness even after exposure to different chemicals, such as acid, base, salt, acetone, and toluene. Importantly, the fabrics maintained superhydrophobicity after 4500 abrasion cycles, 200 laundering cycles, as well as long time exposure to UV irradiation. The fabrics could be applied in oil/water separation due to their superhydrophobic and superoleophilic properties.

Hydrophobic polydimethylsiloxane based coatings were self-roughened on textiles via a nonsolvent-induced phase-separation method. The self-roughened coatings have superior durability in superhydrophobicity. The obtained superhydrophobic and superoleophilic materials were demonstrated as excellent filters for continuous oil–water separation. The work showed large-scale and practical application for consecutive collection of oil from water.

Superhydrophobic surfaces were fabricated via surface-initiated atom transfer radical polymerization of fluorinated methacrylates on poly(ethylene terephthalate) (PET) fabrics. The hydrophobicity of the PET fabric was systematically tunable by controlling the polymerization time. The obtained superhydrophobic fabrics showed excellent chemical robustness even after exposure to different chemicals, such as acid, base, salt, acetone, and toluene. Importantly, the fabrics maintained superhydrophobicity after 2500 abrasion cycles, 100 laundering cycles, and long time exposure to UV irradiation. Also, the surface of the superhydrophobic fabrics showed excellent antifouling properties.Keywords: alkali treatment; antifouling property; SI-ATRP; superhydrophobic;

Maintaining hierarchical roughness and a low surface energy property are keys to long lasting superhydrophobic surfaces. By spraying polystyrene/SiO2 core/shell nanoparticles as a coating skeleton and polydimethylsiloxane as hydrophobic interconnection, lasting and self-healing superhydrophobic surfaces were fabricated. The coating exposed new roughening structures during the rubbing process, thus maintaining a suitable hierarchical roughness, favouring a superhydrophobic property of the surface. Also, the superhydrophobicity of a damaged surface from an air plasma treatment could be automatically restored in 12 h at room temperature or by heat curing and tetrahydrofuran treatment, which helped with the release of hydrophobic polystyrene. This strategy may find practical applications in all kinds of substrates because spray coating is a simple process, and the obtained surfaces possess lasting superhydrophobicity.

Prolonging the lifetime of superhydrophobic surfaces is required so that the materials can be used practically. Thus, great efforts have been made in designing surfaces that maintain micro- and nanoscaled hierarchical structures and low surface-energy property, which are necessary for superhydrophobicity, during use. It was demonstrated that improving surface mechanical strength to increase wear resistance helps maintain hierarchical roughness, retarding the loss of superhydrophobicity. Additionally, designing self-healing materials that can recover their structure and/or properties when damaged has been suggested and demonstrated to sustain the superhydrophobicity of surfaces. This review focuses on recent advances in developing mechanically durable, corrosion-resistant, self-healing, and easily repairable superhydrophobic surfaces, which will enable prolonged lifetime of superhydrophobicity for practical applications in the future.

Rough structures created from bulk materials at the surface could have superior durability. Superhydrophobic colorful surfaces were fabricated through chemical etching of the fiber surfaces, followed by diffusion of fluoroalkylsilane into fibers. The obtained superhydrophobic textiles show strong durability against severe abrasion, long-time laundering, and boiling water.

•ZnO nanostructures were grown uniformly covering around PET fibers.•The ZnO structures were treated by silica to suppress the photoactivity of ZnO.•The textiles decorated with ZnO/silica core/shell structures were hydrophobized.•UV-durable superhydrophobic textiles with UV-shielding properties were obtained.ZnO nanostructures with different morphologies were grown on poly(ethylene terephthalate) fibers by a hydrothermal process at a low temperature of 93 °C. Then the ZnO nanorod decorated fibers were layer-by-layer coated with silica forming ZnO/SiO2 core/shell structures on the textiles, and hydrophobized with hexadecyltrimethoxysilane. Scanning electron microscopy showed that introduction of ZnO nanostructures onto fibers made the textiles roughened dramatically, favoring the formation of superhydrophobic surfaces. Ultraviolet–visible spectrophotometry analysis and contact angle measurement of the textiles showed that growth of ZnO on the fibers enhanced the UV-blocking ability of the textiles, and coating of silica improved not only the UV-shielding property but also the UV-durability of the superhydrophobicity on the textiles.

ZnO nanorod forests were grown wrapping nylon fibers using a two-step process. In the first step, the formation of ZnO seeds at nylon fiber surfaces was induced by the dip coating of ZnO nanosols; in the second step, the growth of the ZnO seeds into nanorod forests was carried out via a wet chemical route in a bath containing an equimolar solution of zinc nitrate hexahydrate and hexamethylenetetramine. The as-obtained ZnO-coated nylon fibers were characterized by scanning electron microscopy, Energy dispersive X-ray spectrum imaging, and X-ray diffraction, respectively. Thermal gravimetric analysis of the pristine and the ZnO-coated nylon fibers was also conducted.

By the complex coating of amino- and epoxy-functionalized silica nanoparticles on epoxy-functionalized cotton textiles to generate a dual-size surface roughness, followed by hydrophobization with stearic acid, 1H,1H,2H,2H-perfluorodecyltrichlorosilane, or their combination, superhydrophobic surfaces were prepared. The static water contact angle of the most superhydrophobic sample as prepared reaches 170° for a 5 μL droplet. The wettability and morphology were investigated by contact angle measurement and scanning electron microscopy. Characterizations by Fourier transformation infrared spectroscopy, and thermal gravimetric analysis were also conducted.

Superhydrophobic poly(ethylene terephthalate) (PET) textile surfaces with a self-cleaning property were fabricated by treating the microscale fibers with alkali followed by coating with polydimethylsiloxane (PDMS). Scanning electron microscopy analysis showed that alkali treatment etched the PET and resulted in nanoscale pits on the fiber surfaces, making the textiles have hierarchical structures. Coating of PDMS on the etched fibers affected little the roughening structures while lowered the surface energy of the fibers, thus making the textiles show slippery superhydrophobicity with a self-cleaning effect. Wettability tests showed that the superhydrophobic textiles were robust to acid/alkaline etching, UV irradiation, and long-time laundering. Importantly, the textiles maintained superhydrophobicity even when the textiles are ruptured by severe abrasion. Also colorful images could be imparted to the superhydrophobic textiles by a conventional transfer printing without affecting the superhydrophobicity.

Maintaining hierarchical roughness and a low surface energy property are keys to long lasting superhydrophobic surfaces. By spraying polystyrene/SiO2 core/shell nanoparticles as a coating skeleton and polydimethylsiloxane as hydrophobic interconnection, lasting and self-healing superhydrophobic surfaces were fabricated. The coating exposed new roughening structures during the rubbing process, thus maintaining a suitable hierarchical roughness, favouring a superhydrophobic property of the surface. Also, the superhydrophobicity of a damaged surface from an air plasma treatment could be automatically restored in 12 h at room temperature or by heat curing and tetrahydrofuran treatment, which helped with the release of hydrophobic polystyrene. This strategy may find practical applications in all kinds of substrates because spray coating is a simple process, and the obtained surfaces possess lasting superhydrophobicity.

Superhydrophobic fabrics were fabricated by creation of roughening structures through alkali etching of fibers, modification with mercapto silanes and hydrophobization via thiol–ene click chemistry. Alkali etching resulted in nanoscale pits on the fiber surfaces roughening the fabrics with hierarchical structures, and improved the affinity of fibers for mercapto silanes. The click reaction between dodecafluoroheptyl methacrylate and sulfhydryl fibers lowered the surface energy, making the fabrics superhydrophobic with superoleophilicity. The as-obtained superhydrophobic fabrics showed excellent chemical robustness even after exposure to different chemicals, such as acid, base, salt, acetone, and toluene. Importantly, the fabrics maintained superhydrophobicity after 4500 abrasion cycles, 200 laundering cycles, as well as long time exposure to UV irradiation. The fabrics could be applied in oil/water separation due to their superhydrophobic and superoleophilic properties.

Hydrophobic polydimethylsiloxane based coatings were self-roughened on textiles via a nonsolvent-induced phase-separation method. The self-roughened coatings have superior durability in superhydrophobicity. The obtained superhydrophobic and superoleophilic materials were demonstrated as excellent filters for continuous oil–water separation. The work showed large-scale and practical application for consecutive collection of oil from water.

Prolonging the lifetime of superhydrophobic surfaces is required so that the materials can be used practically. Thus, great efforts have been made in designing surfaces that maintain micro- and nanoscaled hierarchical structures and low surface-energy property, which are necessary for superhydrophobicity, during use. It was demonstrated that improving surface mechanical strength to increase wear resistance helps maintain hierarchical roughness, retarding the loss of superhydrophobicity. Additionally, designing self-healing materials that can recover their structure and/or properties when damaged has been suggested and demonstrated to sustain the superhydrophobicity of surfaces. This review focuses on recent advances in developing mechanically durable, corrosion-resistant, self-healing, and easily repairable superhydrophobic surfaces, which will enable prolonged lifetime of superhydrophobicity for practical applications in the future.

Rough structures created from bulk materials at the surface could have superior durability. Superhydrophobic colorful surfaces were fabricated through chemical etching of the fiber surfaces, followed by diffusion of fluoroalkylsilane into fibers. The obtained superhydrophobic textiles show strong durability against severe abrasion, long-time laundering, and boiling water.