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Fabricating functional materials that can solve environmental problems resulting from oil or organic solvent pollution is highly desired. However, expensive materials or complicated procedures and unidirectional oil-water separation hamper their applications. Herein, a magnetic superhydrophobic carbon fiber aerogel with high absorption capacity was developed by one-step pyrolysis of Fe(NO)-coated cotton in an argon atmosphere. The obtained aerogel can selectively collect oils from oil-polluted region by a magnet bar owing to its magnetic properties and achieves fast oil-water separation for its superhydrophobicity and superoleophilicity. Furthermore, the aerogel performs recyclable oil absorption capacity even after ten cycles of oil-water separation and bears organic solvent immersion. Importantly, the obtained aerogel turns to superhydrophilic and underwater superoleophobic after thermal treatment, allowing it as a promising and efficient material for bidirectional oil-water separation and organic contaminants removal. [ABSTRACT FROM AUTHOR]

The polyimide (PI)/carboxyl-functionalized multi-walled carbon nanotube (MWCNTs-COOH) nanocomposite films were synthesized by situ polymerization method. The results showed that the incorporation of MWCNTs-COOH greatly enhanced thermal stability and mechanical property of PI. PI/MWCNTs-COOH nanocomposites exhibited better tribological properties under seawater lubrication than other conditions because of excellent lubricating effect of seawater. Besides, the wear resistance of PI under seawater lubrication had been greatly improved by filling MWCNTs-COOH, because strong interfacial adhesion between PI matrix and MWCNTs-COOH nanofillers could transfer load effectively between contact surfaces. In particular, when the content of MWCNTs-COOH was 0.7 wt%, the corresponding PI/MWCNTs-COOH nanocomposites had the best tribological properties under seawater lubrication. Graphical Abstract: The polyimide (PI)/carboxyl-functionalized multi-walled carbon nanotube (MWCNTs-COOH) nanocomposite films were synthesized by in situ polymerization using 4,4′-oxydianiline (ODA), carboxyl-functionalized multi-walled carbon nanotube (MWCNTs-COOH) and pyromellitic dianhydride (PMDA). The tribological properties of PI/MWCNTs-COOH nanocomposite films were measured under dry sliding condition, pure water condition and seawater lubrication condition. This study can provide some guidance to develop polymer materials with excellent wear resistance suitable for ocean environment.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Silica gel shell microcapsules containing ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate ([Bmim][PF]) have been successfully synthesized through an interfacial self-assembly process and solgel reaction. They are further developed as filler to improve the tribological property of polyurethane composite coatings. The tribological behaviors of the polyurethane composite coatings filled with microcapsules have been systematically investigated using ball-on-disk tribological test. The results showed that the polyurethane composite coating filled with microcapsules displayed much lower friction coefficient and wear, compared with that of unfilled one. It is demonstrated that the ionic liquid released from the broken microcapsules during the friction process lubricates the rubbing surfaces and prevents a direct contact between steel ball and coating, leading to a lower friction coefficient and a lower wear width and depth. [ABSTRACT FROM AUTHOR]

In this paper, a new superhydrophobic coating was successfully prefabricated by a facile sol–gel process which was made up of first the surface chemical reaction of (3-Glycidyloxypropyl) trimethoxysilane (A-187) and SiO 2 particles and subsequent spray-coating onto the substrate. Further hardening treatment and surface fluorination allowed the SiO 2 coating with the optimum mass ratio of 2.0:1 to exhibit nice superhydrophobic property and high adhesive effect to substrates. Our researches indicated that the mass ratio of A-187 and SiO 2 particles could significantly control the surface morphology (or the wettability) and affect adhesion force of the superhydrophobic coating to substrates. In the process, hardening temperature was quite important for rapid evaporation of the solvent and then fast hardening of the coating despite the absence of the similar effect to the mass ratio of A-187 and SiO 2 particles on the superhydrophobic coating, and moreover, a higher hardening temperature could also highly improve transparency of the superhydrophobic coating. These findings suggest that the superhydrophobic coating should have promising commercial applications as a self-cleaning product. [ABSTRACT FROM AUTHOR]

Producing fabric composites with improved high-temperature tribological property is highly desired for their use in practical application, yet still challenging. Herein, we employed MoSi 2 as anti-oxidant and filled it into the hybrid PTFE/Nomex fabric/phenolic composite. The high-temperature tribological properties of the fabric composites were evaluated on a pin-on-disk tribometer. The results showed that the MoSi 2 filled fabric composites displayed much lower wear rates in high-temperature environment, comparing to that of unfilled fabric composite. Moreover, the antiwear property of the MoSi 2 filled fabric composite can be further improved by treating the fabric with air-plasma, as the bonding strength between the fabric and resin was evidently enhanced. The wear behaviors and the corresponding wear mechanisms of the composites were discussed based on the characterizations. [ABSTRACT FROM AUTHOR]

Development of functional materials that can remove oil from water by an energy-efficient way is highly desirable yet still challenging. Herein, graphene coated cotton was fabricated by a self-assemble technique. This graphene coated cotton could be used as an oil absorbent material, due to its superhydrophobicity and superoleophilicity. It was found that the oil absorption capacity of the graphene coated cotton differed slightly after ten cycles of oil–water separation. The graphene coated cotton also possessed excellent mechanical properties, resulting from the special texture combined the advantages of graphene and raw cotton. Most interestingly, when applied in conjunction with a vacuum system, the time needs for oil collection was shortened. We believe that this kind of sorbent is a promising candidate for use in large-scale removal of oils from water. [ABSTRACT FROM AUTHOR]

Herein, we studied the combined effect of air-plasma treatment and lubricant filling on the dry sliding wear behavior of hybrid PTFE/Nomex fabric/phenolic composite. In this study, hybrid PTFE/Nomex fabric was firstly treated by air-plasma to improve the fabric-resin adhesion and tribological properties of hybrid PTFE/Nomex fabric/phenolic composite. Subsequently, polyfluo wax was employed as lubricant filler to further improve the anti-wear property of air-plasma treated fabric composite. The results of wear tests showed that polyfluo wax filled air-plasma treated fabric composite exhibited the optimal antiwear property and load-carrying capacity, compared to untreated and air-plasma treated fabric composites. The effects of the air-plasma treatment power and polyfluo wax content on the tribological behaviors of the fabric composites were also investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] A transparent superamphiphobic coating was produced using CNTs as a template. [•] The superamphiphobicity was retained after thermal treatment at 400°C. [•] Surface wettability can be controlled through varying the surface texture. [ABSTRACT FROM AUTHOR]

In recent years, two dimensional hybrid materials have attracted immense attention in tribology field. However, kaolin shows potential value in catalysts and oil lubrication, and rarely in tribology of LC (liner composites). Herein, kaolin/Ag hybrids, in which mono-dispersed Ag nanoparticles (AgNPs) were dotted on kaolin, were prepared via in-situ reduction. The tribological behaviors of kaolin/Ag hybrids-reinforced PBO(poly(p-phenylene benzobisoxazole)/phenolic resin LC were evaluated. The results indicated that wear rate decreased but the friction coefficient slightly increased for sole kaolin filled PBO/phenolic resin LC. However, when kaolin/Ag hybrids were incorporated into PBO/phenolic resin LC, the wear rate and friction coefficient synchronously decreased. To understand the synergistic mechanism, worn surface morphology and a cross section of the tribofilm via FIB-TEM analyses are provided. [Display omitted] • Monodispersed AgNPs are dotted on the kaolin surface proposed kaolin/Ag hybrid via in-situ reduction reaction. • The exfoliated lamellar-kaolin spread over the sliding interface separating directly contact of friction pair. • Released AgNPs served as "nano-bearing" decrease the friction coefficient and improve thermal conductivity of liner. • Kaolin/Ag hybrid play synergistic effect in improving the tribological behavior of PBO/phenolic resin liner composites. [ABSTRACT FROM AUTHOR]

A simple vapor-phasedeposition process has been developed to fabricatea superhydrophobic and superoleophilic sponge using ordinary commercialpolyurethane sponges. The simultaneous properties of superhydrophobicityand superoleophilicity enable the sponge to float on the water surfaceand selectively absorb oil from water. Its uptake capacities of differentoils (motor oil, lubricating oil, pump oil, silicone oil, and soybeanoil) in the oil–water mixtures were all above 20 g/g. The absorbedoil could be collected by squeezing the sponge, and the recoveredsponge could be reused in oil–water separation for many cycleswhile still maintaining a high capacity. This is helpful for realizingthe proper disposal of the oil and avoiding secondary pollution. Asimilar experiment was performed using the as-prepared sponge to removepetroleum from contaminated water. The results suggest that our materialmight find practical applications in the cleanup of oil spills andthe removal of organic pollutants from water surfaces. [ABSTRACT FROM AUTHOR]

Highlights: [•] We fabricated super-repellent cotton textiles by in situ doping polymerization. [•] The textile displayed extreme resistance to wetting from diverse liquids. [•] A rapid and reversible wettability switching of various liquids could be observed. [ABSTRACT FROM AUTHOR]

Abstract: A superhydrophobic perfluorooctanoic acid modified TiO2/polystyrene nanocomposites coating was fabricated by a facile spraying process. As modified by perfluorooctanoic acid, the TiO2/polystyrene nanocomposites changed from hydrophilic (86°) to hydrophobic (166°). The wettability can be adjusted by controlling the drying temperature and the content of modified TiO2 nanoparticles. When the weight ratio of perfluorooctanoic acid modified TiO2 to polystyrene was 1:1, the maximum of contact angle was obtained at 180°C. As the content of perfluorooctanoic acid modified TiO2 increased, the maximum of contact angle was achieved at 100°C. [Copyright &y& Elsevier]

The introduction of functional fillers is very important for enhancing the thermal conductivity and tribological performance of self-lubricating fabric liner composites. In present work, copper yarn was woven into hybrid Nomex/PTFE fabric via an integrated design method to fabricate self-lubricating fabric liner composites. Characterizations using thermal conductivity analyzer and tensile testing machine demonstrated that the copper fiber-reinforced self-lubricating fabric liner composites possessed a better thermal conductivity and yarn pull-out performance. The thermal conductivity and yarn pull-out force of copper yarn-reinforced self-lubricating fabric liner were 0.1814 W/m·K and 2.876 N, which increased by 78.9% and 24.8% compared with that of no-copper yarn-reinforced self-lubricating fabric liner composites, respectively. The results of wear tests indicated that the copper yarn-reinforced self-lubricating liner fabric composites exhibited preferred anti-wear properties. • The thermal conductivity and yarn pull-out strength of self-lubricating fabric liner composites were 0.1814 W/m·K and 2.876 N, which increased by 78.9% and 24.8% compared with composite-0, respectively. • The wear rate of composite-4 was lower than the pure composites under different wear test conditions, which decreased by 59.4 %-83.3 %. • The tribological performance of self-lubricating fabric liner composites acquired obviously enhancement, which was owing to the thermal conductivity network path formed by copper fiber. [ABSTRACT FROM AUTHOR]

Alginates are natural unbranched polysaccharide and have been extensively investigated because of their biocompatibility and superior gel-forming properties. However, the tribology functions of alginate hydrogels still remain largely unexplored. Here, we develop a facile method for reducing friction and wear between polymer-metal friction pairs. The using of gluconic acid- δ -lactone (GDL) is important to regulate gelation time and induce complete, uniform gelation of alginates by in situ release Ca2+. After the addition of graphene, the friction coefficient and wear volume decline with ratios of 37 % and 50 %, respectively. The effective isolation of friction pairs and the release of water molecule owning to the self-decomposition of alginate hydrogels together contribute to reduce friction and wear. [ABSTRACT FROM AUTHOR]

Preparing nanoparticles with hierarchical structure is a promising approach to improve the interfacial adhesion between additives and polymer matrix. Herein, we exploited hydrothermal carbon spheres (HCSs) decorated with amino-functionalized UiO-66 (UiO-HCSs) to enhance the mechanical and tribological properties of ultra-high molecular weight polyethylene (UHMWPE) composites. Experimental analyses of the morphologies and chemical structure indicate the successful growth of Zr-based metal-organic frameworks (MOFs) on the surfaces of HCSs. The comprehensive studies reveal the beneficial effects of mulberry-like UiO-HCSs nanoparticles on the interfacial properties. The transfer of Zr-based materials onto the steel counterpart also contributes to decrease the wear rate of UHMWPE composites. Furthermore, the present work may pave a route for applying MOFs to tribology. • Decorating carbon spheres with Zr-based MOFs. • Enhancing mechanical and tribological performances of UHMWPE composites by incorporating UiO-HCSs. • Disclosures about different wear mechanisms of UHMWPE composites. [ABSTRACT FROM AUTHOR]

Interfacial properties between reinforcement and resin matrix have significantly influence on the tribological and mechanical behaviors of self-lubricating liner composites. Introducing nanoscale fillers onto fibers surface can significantly enhance the surface energy and roughness, which contributed to improve the adhesion strength. In this work, MgAl-LDH/PAMPA multilayers films were loaded onto Nomex and PTFE fibers surface by a simple and high efficiency Layer-by-Layer (LbL) self-assembly approach. The tensile strength of the LbL-9 composite was 111.54 MPa, which increased by 11.58% compared to that of pristine composites (99.96 MPa). Moreover, the bonding strength of LbL-9 composites was 40.8% higher than that of pristine one. Meanwhile, friction and wear tests results proved that MgAl-LDH/PAMPA modified composite displayed preferable tribological properties. • • MgAl-layered double hydroxide nanosheets were successfully fabricated.MgAl-LDH multilayers films constructed on fibers surface via LbL self-assembly technique. • Tensile strength, bonding strength and tribological properties were significantly improved. [ABSTRACT FROM AUTHOR]

[Display omitted] The shortage of drinking water has become a global problem, coastal cities can make full use of abundant seawater resources by desalination technology to ease the contradiction between supply and demand. However, fossil energy consumption contradicts the goal of reducing carbon dioxide emissions. Currently, researchers favor interfacial solar desalination devices relying only on clean solar energy. Based on the structure optimization of the evaporator, a kind of device composed of a superhydrophobic BiOI (BiOI-FD) floating layer and CuO polyurethane sponge (CuO sponge) is constructed in this paper, with its design advantages presented in the following two aspects: 1. The novel BiOI-FD photocatalyst in the floating layer reduces the surface tension and realizes the degradation of the enriched pollutants, ensuring the device to achieve solar desalination and inland sewage purification; 2. CuO sponge can inhibit salt crystallization and realize the combination of the water transport and photothermal layers. Particularly, the photothermal evaporation rate of the interface device reached 2.37 kg m−2 h−1.The novel interface evaporator design will bring a new solution for solar desalination, sewage treatment and large-scale application. [ABSTRACT FROM AUTHOR]

In order to improve the photocatalytic capacity of Bi 2 WO 6 , methods including crystal facet modulation, high-temperature treatment, heterojunction construction and quantum dot doping are often used. Therefore, it is necessary to synthesize a high-performance Bi 2 WO 6 photocatalyst through simple preparation methods. Here, a two-step method was used to improve the photodegradation activity of Bi 2 WO 6 by 27.5 times: 1) Stir at room temperature; 2) Dry at 80 °C. It is demonstrated that the improved photocatalytic performance of octadecanethiol-modified superhydrophobic Bi 2 WO 6 (SH-Bi 2 WO 6) is caused by the reduced band width from 2.69 eV to 2.1 eV. Meanwhile, SH-Bi 2 WO 6 can be loaded to glass and fabric surface through spraying method. Thus, superhydrophobic glass (contact angle is 162º) with self-cleaning performance and superhydrophobic fabric with a size of 0.4 m × 0.4 m were obtained. [Display omitted] • The photodegradation ability of Bi 2 WO 6 was improved 27.5 times under mild conditions. • Bi 2 WO 6 photocatalyst with self cleaning performance was obtained by spraying method. • The 0.4 m × 0.4 m fabric was synthesized to verify the large-scale preparation. [ABSTRACT FROM AUTHOR]

The effects of solid loading on the fabrication of ceramic microparts by soft molding were studied. Alumina microchannel parts of different dimensions (60–160 µm) were fabricated from well-dispersed suspensions with different solid loadings (70, 75 and 80 wt%). The structural integrity of the green microchannel parts was examined to study the moldability of the suspensions. It was found that the minimum feature size and linear shrinkage of the microchannel parts decreased with increasing solid loading, while the green density and sintered density showed the opposite trend. The reasons for incomplete filling and demolding failures were also discussed. [ABSTRACT FROM AUTHOR]

Hydrophobic surface for drag reduction on marine vehicles and structures has been proposed for many years. However, the drag reduction effect has been found to be unstable under high flow speed/pressure conditions because of the destruction of air-water interface. In this paper, an air layer was maintained experimentally by continuous air injection on hydrophobic surfaces. Good hydrophobicity was found to benefit the spread of air bubbles and the formation of a wide and flat air layer on solid surfaces. Based on this recognition, a method combining air injection and surface hydrophobicity adjustment was proposed to maintain the air layer. Through flow field analyses, it has been found that the roughness of irregular micro-structures on superhydrophobic surfaces became dominant and the frictional drag was increased in the Wenzel state. However through air injection, the Cassie state was able to be recovered and the slip could also be re-formed at the solid surface. Because of the slip effect, vortices and shears in the turbulent boundary layer were restrained, and a drag reduction up to 20% was obtained in the study. This method was promising to maintain a robust air-water interface on superhydrophobic surfaces and sustain the drag reduction effect in engineering applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • The multifunctional floating layer is constructed by co-sedimentation method. • Polyurethane sponge was used as a hydrogel growth template. • Bismuth oxychloride has the photothermal conversion and photodegradation properties. In order to solve the pollution faced by traditional evaporators, an interface evaporator containing a floating unit and a bismuth oxychloride composite hydrogel unit was constructed. The innovation lies in: 1. The infiltrating behavior of the floating unit is non-wetting; 2. The water contact angle of the floating layer is 160° and the construction strategy can be extended to sponges, fabrics and felts. The obtained bismuth oxychloride composite hydrogel retained an excellent water supply and salt suppression capacity, with the water droplets expanding within 120 ms and reaching a steam production rate of 1.82 kg·m−2·h−1. From band structure calculation, the conduction and valence band are −0.928 eV and 1.502 eV, respectively. Comparative experiments and ESR analyses demonstrated the h+ degraded species. It is hoped that the construction of the above interface evaporator could bring a new solution for environmental restoration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sodium alginate hydrogels were grown in situ on the graphite felt surface. • A novel self-floating solar evaporator was synthesized. • The synchronization of clean water production and environmental remediation. At present, the shortage of drinking water caused by environmental pollution hinders social development. The advent of solar interface evaporation systems provides an effective solution for clean water production. However, the issue of residual pollutants has not been adequately addressed. In this paper, we introduce BiOBr into the floating layer, which not only increases the roughness to achieve superhydrophobic performance but also photodegrades soluble pollutants. Additionally, to overcome the poor water supply capacity of carbon felt, we propose the use of a sodium alginate hydrogel, which reduces the evaporation enthalpy to 1690 J/g and increases the steam flux to 1.99 kg m−2 h−1 under 1 sun irradiation. It is hoped that the design strategies presented in this paper will provide a reference for optimizing solar evaporation systems and enhancing environmental purification. [ABSTRACT FROM AUTHOR]

Superhydrophobic materials has attracted considerable attention due to their usage in wide range of practical applications. However, in practical conditions, inevitable high discharge of VOC and dust particles in the common spraying method could be very harmful to the environment and workers as well. Herein, modified silica nanoparticles were combined with a commercial PDMS to obtain a non-fluoride transparent superhydrophobic coating cured at ambient temperature via an environment-friendly method of brushing. The coating can be fabricated on a wide range of substrates in a short time of only two minutes. The coating demonstrated excellent thermal stability upto 360 °C and corrosion resistance in electrochemical testing. Owing to the short fabrication process, the coating can be readily repaired by prompt brushing after being destroyed. With ultra-easy fabrication, it is expected that the coating has a great potential for practical application with different requirements such as low pollutant discharge, high transmittance, good thermostability or corrosion resistance. [ABSTRACT FROM AUTHOR]

The shortage of drinking water and water pollution are the two major problems facing social development. Although being successful in the production of clean water, traditional interface evaporators are ineffective in the removal of dissolved and non-water-soluble pollutants. This paper follows the design of interface evaporators, with superhydrophobic canvas, filter paper and CuO/Cu 2 O/copper foam serving as the floating layer, the water transport channel and the photothermal transfer layer respectively. An evaporation rate of 1.18 kg•m−2•h−1 was obtained using the constructed interface evaporator, which had the ability to selectively adsorb floating organic solvents owing to the non-wettability of the floating layer, while the floating layer it had the performance of photodegradable soluble dyes due to the existence of Bi 2 WO 6. [Display omitted] • An interface evaporator with a sandwich structure was constructed. • The presence of Bi 2 WO 6 endowed the floating layer with photodegradation ability. • CuO/Cu 2 O/copper foam was used as the photothermal layer. [ABSTRACT FROM AUTHOR]

[Display omitted] • A sodium alginate hydrogel was successfully grown on the aerogel surface. • The designed solar steam device had the self-floating characteristic. • Bismuth molybdate was introduced into the floating layer to degrade dyes. It is a challenge to construct devices for producing clean and purified water. In this paper, devices assembled using an aerogel-hydrogel composite and a floating layer were used to produce clean water while purifying water sources. A low-surface-tension polymer and bismuth molybdate were loaded to the surface of a carrier through co-deposition. The contact angle of the constructed superhydrophobic fabric, canvas and felt was 162°, 159° and 160° respectively. Even under the external force of deformation, the beads still quickly left the surface, showing a low adhesion effect. The purification efficiency of the assembled self-floating solar steam generator was 99.82 % and 99.48 % for rhodamine B (Rh B) and methyl orange (MO) respectively, whose mechanical stability and salt suppression capacity were demonstrated through stress–strain curves and photothermal experiments with a high saline concentration (10 wt% NaCl). Through the introduction of bismuth molybdate in the floating layer, not only the roughness increased, but the properties of photodegradation performance were also achieved. Through an active substrate capture test and a band structure analysis, the h+ played a decisive role in the degradation process. The valence and conduction band position of the catalyst were 2.28 eV and −0.35 eV, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • A superhydrophobic Bi/BiOCl photocatalyst was synthesized. • The floating layer with photodegradation performance was constructed. • The PMDA-TAPA COF photothermal layer expands the application range of the solar evaporator. Solar interface heating evaporators are widely used and have been able to obtain clean water vapor from sewage. However, the soluble contaminants remaining in the original solution were not removed, and the floating organic pollutants affect the steam production rate. In this paper, the superhydrophobic Bi/BiOCl with low surface tension is synthesized and loaded to the felt to construct the floating layer of the photothermal device. The floating layer collaborated with the filter paper hydrophilic layer and the Pyromellitic dianhydride-Tris (4-aminophenyl) amine covalent organic framework (PMDA-TAPA COF) photothermal layer to treat the sewage containing dissolved pollutants, achieving an interfacial evaporation rate of 1.47 kg⋅m−2⋅h−1. Importantly, the floating layer not only has a contact angle of 161°, which can selectively adsorb the organic solvents floating on the water surface, but also can degrade the pollutants dissolved in the water under the light and solving the problems that hinder device applications. The valence band and conduction band potentials of superhydrophobic Bi/BiOCl are at 3.065 eV and −0.435 eV, respectively, which produce h+ and O 2 – under light to degrade dissolved pollutants in water. The introduction of novel superhydrophobic Bi/BiOCl photocatalyst in the floating layer provides a reference for solving the problem of pollutant residues. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pollutants in bulk water can be removed during steam generation. • The raw materials of solar interfacial evaporator come from daily life. • The evaporation rate of the evaporator is 4.2 times that of pure water. • The evaporator has the performance of salt inhibition. It is crucial for relieving the shortage of clean water in inland to construct an economical photothermal interfacial evaporator with a function of solving the enrichment of dyes during clean water production. Herein, a photothermal interfacial evaporator satisfying the above acquirement is constructed, in which BiOBr with oxygen vacancies (BiOBr-OVs) serves as photothermal material, which lays a foundation for preparation of a photothermal interfacial evaporator with an ability of avoiding dyes aggregation during clean water production. Furthermore, the raw materials except photothermal material and sodium alginate coating of the evaporator are from daily life, which reduces its cost. Importantly, the evaporation rate of the evaporator under one sun illumination is 4.2 times that of pure water (0.39 kg·m−2·h−1). Meanwhile, it also exhibits a purification efficiency of 99.9 % for Rh B solution. Noteworthily, Rh B in bulk water is photodegraded by the evaporator during steam generation under one sun illumination and its photodegradation efficiency is 99.9 %, indicating that the evaporator is capable of preventing dye aggregation during water evaporation. Besides, the evaporator has desalination performance, in which its steam generation rates in 3.5 wt% and 10 wt% NaCl solution are attenuated only by 1.23 % and 3.07 %, respectively, compared with that of in pure water. Meanwhile, the removal efficiency of the evaporator for K+, Na+ and Mg2+ in simulated seawater is 99.98 %. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The problem of BiOBr recycling is solved. • The superhydrophobicity and degradation property has been combined. • Both oily and water soluble pollutants can be removed. • The degradation performance remained stable after cyclic tests. Abstract Materials with superhydrophobicity have been successful in removing and recovering oily pollutants in water, however, it cannot get rid of water soluble pollutants. In this paper, we prepared a superhydrophobic Cu-BiOBr surface which combined the superhydrophobicity with the photodegradation property to realize the oil/water separation and the removal of water-soluble pollutants. The result shows that the surface of the material has macroporous (620 nm) and mesoporous (3.2 nm) structure. The degradation efficiency for Rhodamine B (Rh B) does not change after 5 times of repeated use, which indicates the good degradation stability of the material. In addition, the surface remains superhydrophobic and high flux for up to 11 cycles. The preparation process is simple and economical with no complicated and expensive equipment but only filtration and spraying used. A 13 cm × 13 cm superhydrophobic Cu-BiOBr mesh was also prepared to verify the feasibility of large scale fabrication. [ABSTRACT FROM AUTHOR]

• The device has a steam generation rate of 2.81 kg·m−2·h−1 under 1 sun illumination. • The device shows the performance of anti-fouling and salt-resistance. • Contaminants remaining in the bulk water can be removed after steam generation. The limitations of a single-function solar-driven interfacial evaporation device applied to unpurified water (brine and wastewater) with a complex composition have been exposed. Herein, a solar-driven photothermal evaporation device with the nature of salt-resistance as well as removal of Rh B remaining and oil slicks in bulk water is established through a novel design, with the aim of breaking the current limitations. Concretely, the oil slicks (toluene and cyclohexane) and residual Rh B in bulk water are eliminated by the superhydrophobic part of the device, which makes it possible to protect the device and the environment from the negative effects of oil slicks and the enrichment of dyes. Furthermore, the purification efficiency of the device is above 99.9 % for heavy metal ions and 99.9 % for Rh B solution. Then, the device shows evaporation rates of 2.81 kg·m−2·h−1 (deionized water), 2.77 kg·m−2·h−1 (3.5 wt% NaCl solution), and 2.60 kg·m−2·h−1 (10 wt% NaCl solution) under one sun illumination in different water sources. Meanwhile, the salt-resistance mechanism of the device is the passive transport of salt solution with high concentration between the bulk water and the evaporation surface, which is ascertained through the salt flow being observed in bulk water. A great potential is revealed in the device in desalination and wastewater purification. [ABSTRACT FROM AUTHOR]

Through surface sulfonation and neutralization, amino-terminated block copolymer can be successfully grafted onto graphene surface with the content as high as 81.9 wt%, leading to the macroscopic fluidity of graphene in the absence of solvents at room temperature and the unfolded morphologies in microscopic scale. The excellent solubility of the liquid-like graphene enables the well-dispersion of graphene in a wide spectrum of solvents for a long time. As a lubricant additive in water, the maximum reduction of the friction coefficient and wear rate can reach to 53% and 91% compare with water, which may be due to the formation of tribo-film on the contact interface by electrostatic adsorption and molecular rearrangement of the liquid-like graphene. [ABSTRACT FROM AUTHOR]

The thermal stability of polymer matrix composite could effectively improve by incorporation of highly thermally conductive ceramic materials into polymers. In present work, hybrid PTFE/Nomex fabric/phenolic composite specimens were prepared with zirconium diboride (ZrB 2 ) particles for the improvement its high-temperature tribological performances. The thermal stability of hybrid PTFE/Nomex fabric/phenolic composite was investigated by TGA. The result showed that the thermal stability was improved because of addition of ZrB 2 particles. In addition, it was found that 9 wt% ZrB 2 reinforced hybrid PTFE/Nomex fabric/phenolic composite exhibited optimal tribological performances compared to unfilled fabric composite under all test conditions. [ABSTRACT FROM AUTHOR]

Interfacial strength between reinforcement and polymer matrix and dispersion of lubricant fillers in polymer composites are vital properties in determining the mechanical behaviors and tribological performance. In this work, a facile biomimetic method was employed to improve the interfacial strength between hybrid PTFE/Nomex fabric and phenolic resin as well as the dispersion of carbon carbonaceous in phenolic composite. Dopamine is the main component of mussel adhesive proteins which can easily attach on substrate surface by self-polymerization under weak basic buffer solution. Hence, polydopamine modified graphene oxide (D-rGO) and multi-walled carbon nanotubes (D-MWCNTs) were incorporated into polydopamine functionalized hybrid PTFE/Nomex fabric (D-fabric) composite to improve the tribological performance of the phenolic composite. XPS, TGA, SEM, and TEM characteristics illustrated that the hybrid PTFE/Nomex fabric, graphene oxide (GO), and carbon nanotube (MWCNTs) were successfully functionalized by polydopamine. More importantly, wear test results showed that D-rGO (or D-MWCNTs) reinforced D-fabric phenolic composite exhibited excellent tribological performance. The wear test results and corresponding wear mechanisms of the hybrid PTFE/Nomex fabric composite were discussed in terms of characterizations. [ABSTRACT FROM AUTHOR]

The design of multifunctional materials with durability under extreme conditions has raised considerable interest for their highly practical potential. Thus, we developed an efficient and technically simple method to prepare easily repairable and rapid self-healing superhydrophobic fabrics, which only involves one-step coating of polyfluorowax (PFW)/graphite fluoride (GF) complexes. The resulting waterproof fabrics can be easily repaired without any complicated and expensive fabrication procedures. Importantly, the fabrics with a self-healing function can rapidly and repetitively restore the superhydrophobicity when the hydrophobicity is damaged owing to the regenerated fresh surface on the fibers induced by heating. Furthermore, the fabrics can maintain their water repellency even was seriously damaged during the abrasion and mechanical stretch tests. In addition, the self-healing fabric can be further dyed and still exhibits satisfactory durability against strong acidic or alkaline, high temperature and humidity, freezing environment and long-term UV exposure. [ABSTRACT FROM AUTHOR]

Designing multifunctional and fluorinate-free liquid-repellent materials via a facile and scalable method is highly desired. Herein, a transparent, durable, and self-cleaning superhydrophobic coating based on trimethoxypropylsilane-silica nanoparticles sol solution was prepared by one-step process. Once spray deposited on glass substrates, the transparent superhydrophobic self-cleaning glass with high water contact angle (158.5°) as well as low sliding angle (3.9°) was obtained. The transmittance of coated glass substrates is above 80 % in visible-light region (400-800 nm). Moreover, the prepared coatings kept stable superhydrophobicity under extreme environment conditions of high temperature and humidity, high or low temperature, and UV light irradiation. Water droplets could still roll off the obtained surface easily after examined by water impact and lacerating the surface with a knife. In addition, this versatile and environmentally benign approach can be applied on wide substrates readily by using spraying or dipping technique without any extra surface treatments. Therefore, our method may provide extensive applications in optoelectronics, liquid-repellent coatings, and oil-water separation. [ABSTRACT FROM AUTHOR]

Development of superhydrophobic materials that can remove oil pollutant from water by an energy-efficient way is highly desirable. In this study, we present a novel composite material base on commercially available polyurethane foams functionalized with magnetic superhydrophobic nanoparticles, which can be used for removal of contaminants from water. In addition to the water repellent and oil absorbing capacities, the functionalized foams exhibit magnetic respond. When a piece of coated foam was placed on the surface of oil/water mixture, the foam could be manipulated to the oil-polluted region by magnet bar; they can absorb the floating oil from the polluted regions, hence purifying the water underneath. This low cost process can easily be scaled up to clean large area oil spills in water. [ABSTRACT FROM AUTHOR]

In this work, we investigated the effect of air-plasma treatment on the bonding strength of hybrid PTFE/Nomex fabric and mechanical strength of PTFE and Nomex fibers. Besides, we employed hexagonal boron nitride (h-BN) as high-temperature lubricant and incorporated it into the hybrid fabric/phenolic composite. The high-temperature tribological performances of the fabric composite were evaluated on a pin-on-disk tribometer. The results indicated that the air-plasma treated hybrid PTFE/Nomex fabric composites filled with 6 wt% h-BN exhibited outstanding tribological properties. The results of the morphology study of the fabric composites support the results of the wear test and the corresponding wear mechanisms of the composites were discussed based on the characterizations. [ABSTRACT FROM AUTHOR]

The polyimide (PI)/graphene oxide (GO) nanocomposite films were synthesized by situ polymerization and their tribological behaviors under dry friction, pure water lubrication and seawater lubrication were comparatively investigated. The results showed that PI/GO exhibited better tribological properties under seawater-lubricated condition than other conditions because of excellent lubricating effect of seawater. Besides, the wear resistance of PI had been greatly improved by filling GO under seawater lubrication and reached the top when the content of GO was 0.5 wt%, because strong interfacial adhesion between PI matrix and GO nanofillers could transfer load effectively between the contact surfaces. [ABSTRACT FROM AUTHOR]

The lack of robust interphases bonding between carbon fiber (CF) and polyimide (PI) polymer composites can be tackled by growing homogeneous copper oxide (CuO) nanowires 2 ∼ 3 μm on the surface of the CFC. The CuO nanowires can improve the interface compatibility with PI, and introduce a lubricating phase into PI/CuO@CFC composite to boost its mechanical and tribological performance. Compared to PI/CFC composites, PI/CuO@CFC composites were given a lower friction coefficient (45% lower), as well as a narrower wear width (47% lower), and the tensile strength increased by 43%. The enhancement mechanism is proposed via the analysis of the composite interface and worn surface. Therefore, it is an effective method to grow CuO nanowires for preparing high-performance PI/CFC composites, and has important application prospects in tribology field. • Uniform CuO nanowires on CFC can improve interfacial bonding with PI matrix. • PI/CuO@CFC composites exhibited improved mechanical and tribological properties. • Growth of CuO nanowires is an ideal way to obtain high performance composite. [ABSTRACT FROM AUTHOR]

• Modular design of 3 D photothermal device. • CdS/Bi 2 MoO 6 heterojunction was introduced to the non-wetting floating layer. • Ethanol was used as a "switch" for the wetting transition. Potable water shortage and environmental pollution are two major challenges in terms of the development of human society. Inspired by plant transpiration in nature, 3 D photothermal devices are assembled, mainly including: a floating layer composed of hydrophobic Co 3 O 4 and compound photocatalyst, a hydrophilic layer and a Co 3 O 4 photothermal conversion layer. Non-wetting fabrics not only realizes the photothermal device floating on the water surface, but also obtains the ability of removing the organic solvent and water-soluble pollutants. The fabric surface remained non-wettable, proving its mechanical and temperature stability after blade scraping, surface adhesion, sandpaper grinding and a treatment at 300 °C. The photoresponse ability and degradation of pollutants are improved by forming a heterojunction between composite catalyst, and the O 2 – is verified as the main active species. A vapor production rate of 2.34 kg•m−2•h−1 under 2 sun illumination is achieved through the 3 D photothermal device. The modular design provides guidance for the flexible application of 3 D photothermal devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The device for preparation was simple and complex packaging process was avoided. • The superhydrophobic COF/GO X composite was obtained by one-step method without any subsequent surface treatments. • The synergistic effects of COFs and GO overcome the problems of poor stability of GO in water and easy agglomeration of COFs. • The prepared COF/GO 50 coating has high flux for separating oil/water mixture and good acid and alkali resistance. Covalent organic frameworks (COFs) have been emerged as potential coating material because of their rigid porous structure and excellent chemical stability, however, the challenges of complicated preparation process and poor processability are still remained. As a widely used composite matrix, graphene oxide usually suffers from swells and poor acid/base resistance caused by the weakening of π-π interaction between graphene sheets with large interlayer spacing in an aqueous environment. Currently, it is a trend to combine COFs and graphene oxide to utilize their synergistic effect in materials. In this study, a simple one-step method is developed to prepare hybrid materials based on COFs and GO without using any special device generally required for COFs fabrication. Significantly, synergistic effects of COFs and GO which can improve the acid /alkali resistance of GO in water as well as overcome the COFs' tendency to agglomeration further make the hybrid materials stable in separation process. The hybrid materials formed by COFs polymerization and parallel covalent linking to GO were translated into recyclable superhydrophobic composite coating by spraying onto filter paper. The fabricated coatings presented ultra-high oil/water permeation flux of 26,000 L m-2h−1 bar−1 with > 98% separation efficiency. Moreover, the coating exhibited exceptional chemical stability in acid and basic environment with excellent cycling stability. The simple methodology presented here will be expected to open up a new route for the fabrication of COFs based hybrid materials for wide range of applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy is presented to design robust and recyclable superhydrophobic materials. • Degradation and efficient recycle of samples are realized in waterborne condition. • Environmental issues caused by hydrophobic particles are also resolved. • The obtained monoliths possess both mechanical stability and chemical tolerance. Superhydrophobic materials have many exceptional properties e.g. self-cleaning, anti-icing; to address the increasing demands of their practical usage, most research have been focused on how to improve their robustness. However, it becomes increasingly challenging to recycle robust superhydrophobic materials for their high mechanical, chemical and thermal durability. Here we develop a strategy to synthesize and recycle robust superhydrophobic composites that consist of hydrophobic particles (HPs) and poly hexahydrotriazine (PHT). The superhydrophobic PHT-HPs composites demonstrate high mechanical and chemical robustness, which had a wear rate of only 1.90 wt% in a 30-min ball-on-disk wear test, and retained superhydrophobicity after 100,000 cm of sandpaper abrasion and 3-himmersion in acid and alkali solutions. Tiny volume of ethanol was used to pre-wet the superhydrophobic PHT-HPs composites and acted as a "key" to initiate the recycling process, followed by rapid degradation of PHT using waterborne acid solutions. The recycling rate of HPs and PHT were both higher than 90% even after three recycling loops. This strategy is expected to give a new prospective to fabricate degradable, recyclable and robust superhydrophobic materials in an environmental-friendly way, in order to reduce the potential pollution to the environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unique mushroom-like structures were controllable synthesized by bottom-up method. • The superhydrophobic mesh can serve as marine vehicle with high sailing velocity. • The superhydrophobic mesh possessed superior loading capacity and drag resistance. Generally, the elaborate design of hierarchical micro-nano structures always suffers from high cost and complex procedures, such as laser lithography and plasma etching. Herein, we developed a novel strategy to in-situ fabricate mushroom-like structures constructed by nanowhisker-nanowire hierarchical architectures on copper mesh through a more flexible bottom-up method. The final morphology is highly controlled by adjusting corresponding synthetic conditions. The superhydrophobic copper mesh with a static contact angle of 151.8° and a sliding angle of 3.6° possesses superior anti-fouling and self-cleaning performances towards pollution of daily drinks and dirt. In virtue of the introduction of polydimethylsiloxane (PDMS), the tolerances of superhydrophobic mesh are greatly prolonged more than 24 h in extreme solutions including pH = 1 ~ 14 solutions and 3.5 wt% NaCl solution. Moreover, the superhydrophobic copper mesh presents excellent drag resistance with a high sailing velocity of 25.38 cm s−1 and a large loading capacity (7.34 times) on water. Therefore, the as-prepared mesh exhibits huge potentials for serving as a marine vehicle with a high sailing velocity, which shows satisfying tolerance in extreme environments. It is expected that this research can pave the way to elaborating hierarchical structures on solid surfaces through manageable bottom-up approaches. [ABSTRACT FROM AUTHOR]

Co-MOF (cobased metal-organic frame) nanosheets were developed onto the surface of PBO (poly(p-phenylene benzobisoxazole)) fabric, and OMMT (modified montmorillonite) was incorporated into phenolic resin synergistically to improve the wear resistance of PBO/phenolic resin composites. Co-MOF nanosheets with a large specific surface area exhibited strong interlocking and excellent compatibility between the fabric and resin. In addition, OMMT possessed excellent affinity with phenolic resin and a larger lamellar space, and then polymer chains could be conveniently entangled into interlayers, which further confined the movement of molecular chains caused by friction heat. In addition, a weak interlayer force was conducive to facilitating the formation of a uniform and robust transfer-film on the counterpart. It was demonstrated that the Co-MOF@PBO/OMMT composites presented optimal tribological behavior due to the synergistic effect between interfacial modification and OMMT reinforcement., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Designing functional materials that can be used for oil-water separation in an efficient and cost-effective process is highly desired yet still challenging. Herein, three functional materials used for oil-water separation are readily produced by a dip coating process. Three typical porous materials including copper mesh, fabric, and sponge were dipped into the solution of polyfluorowax-hydrophobic SiO2 to alter their surface texture and chemistry, allowing them to exhibit superhydrophobic property. It was found that the resulting superhydrophobic copper mesh and fabric can be used as a membrane to separate oil-water mixture efficiency; while the obtained superhydrophobic sponge was demonstrated as an oil sorbent scaffold to absorb oil from the oil-water mixture selectively. More importantly, these superhydrophobic materials can retain their oil-water separation efficiency even after 10 cycles of oil-water separation., (Copyright © 2014 Elsevier Inc. All rights reserved.)

We have reported an easy means in this paper to imitate the "lotus leaf" by constructing a superhydrophobic surface through a process combining both electroless galvanic deposition and self-assembly of n-octadecanethiol. Superhydrophobicity with a static water contact angle of about 169 +/- 2 degrees and a sliding angle of 0 +/- 2 degrees was achieved. Both the surface chemical compositions and morphological structures were analyzed. We have obtained a feather-like surface structure, and the thickness of the Ag film is about 10-30 microm. The stability of the superhydrophobic surface was tested under the following three conditions: (1) pH value from 1 to 13; (2) after freezing treatment at -20 degrees C; (3) at ambient temperature. It shows a notable stability in that the contact angle of the sample still remained higher than 150 degrees in different conditions. It can be concluded that our approach can provide an alternative way to fabricate stable superhydrophobic materials.