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How to understand the effect of the surface microstructures and chemical compositions on the anticoagulant properties is the key to develop novel anticoagulant materials. In view of the special surface microstructures and low surface free energy of superhydrophobic materials, it is expected that excellent anticoagulant properties can be obtained from superhydrophobic materials. Here, various nanocone‐shaped ZnO films were prepared by electrochemical deposition method followed by hydrothermal method and modified with n‐dodecyl mercaptan. Ordered nanocone‐shaped ZnO arrays are easier to obtain under suitable preparation conditions and can exhibit superhydrophobicity. The surface wettability is related to the ratio of the diameter and spacing (d/l) of ZnO nanocones. When the d/l value is 0.25–0.55, the contact angle (CA) is consistent with the Cassie mode; when the d/l value is 0.55–0.65, it corresponds to the Wenzel mode. Although the d/l value of the nanocones cannot directly determine the value of the surface free energy, which is strongly associated with the contact mode of the droplets on the film surface. Furthermore, the relationship among surface morphology, CA, and surface free energy is established, and the influence of surface morphology and surface free energy on blood contacting with foreign bodies is explored. It is found that the surface wettability of blood contacting with foreign bodies has some characteristics similar to that of general fluids. For example, under the same contact mode, although the CA of blood on the surface of ZnO nanofilms is about 20° smaller than that of water on the whole, the variation of CA with surface roughness is the same as that of general fluids. However, it also has some unique characteristics, such as the surface of ZnO nanofilms modified with hydrophobic material, the CA becomes larger. These characteristics are of special significance for the development of blood compatibility of superhydrophobic nanomaterials. [ABSTRACT FROM AUTHOR]

The anticoagulant properties of materials are easily affected by the surface properties, which provide belief for designing and developing effective anticoagulant materials to achieve long‐term stable application of blood‐contacting implants and devices. Here, various nanocone‐shaped ZnO films were prepared by simple electrochemical deposition followed by hydrothermal method, and modified with polyethylene glycol (PEG10000, a hydrophilic substance). The influence of surface morphology and surface free energy on the anticoagulant properties of ZnO nanofilms was explored. Both hydrophilic (CA < 40°, surface modified with PEG10000) and superhydrophobic (CA > 150°, surface with rough needle‐like structure) ZnO nanofilms have good anticoagulant properties. Compared with the free energy of the film surface, the surface microstructure of ZnO nanofilms has a greater impact on the anticoagulant properties. After the ZnO nanofilms were modified with PEG, the contact model of water on the surface conforms to the Wenzel model instead of the Cassie model. The number of adhesive platelets was largely reduced, and the hemolysis rate is less than 5%, indicating the better blood compatibility. These characteristics are of special significance for the development of nanomaterials with good anticoagulation. [ABSTRACT FROM AUTHOR]

With the continuous development of bionics, such as, geckos and virginia creeper with both superhydrophobic and super‐adhesive, the surface wetting and super‐adhesive properties of various porous materials have attracted extensive attention of the scientific and medical communities. Here, the honeycomb polyurethane (PU) porous films with strong adhesion were successfully prepared by microphase separation method and the effects of growth parameters on their microstructure and adhesive strength to ice were investigated. It was found that a high relative humidity (e.g., 100%) and a low solution concentration (e.g., 2%) facilitated the formation of ordered honeycomb PU porous films, and as‐prepared PU pores with average pore diameter as small as 5 μm are better ordered and more uniform than these in related documents. Although the contact angle of water droplets on the surface of PU porous films increased from the premodification value of 85–130° to more than 160° after surface modification with polydopamine (PDA), the corresponding rolling angle remained approximately constant (180°), indicating that the surface of PU porous films has strong adhesion similar to geckos and virginia creeper. Furthermore, at lower temperature, the PU porous films exhibited the high adhesive strength of 142.13 kPa on ice, which was strongly dependent on the porous microstructures and surface compositions. The improved adhesive behavior to ice of honeycomb PU porous films modified with PDA provides new strategies for surface modification of materials and potential applications in medical domain. [ABSTRACT FROM AUTHOR]

In this paper, 304 stainless steel-based ZnO (304SS-based ZnO) seed layer was prepared by using sol-gel method or electrochemical deposition. Superhydrophobic nano-ZnO (CSS–ZnO) surface were prepared on its surface by hydrothermal method. The results show that different structural morphologies of 304SS-based ZnO surface were prepared by varying different seed layer preparation methods. In the static icing test, compared with hydrophilic nano-ZnO (SS–ZnO) surface, hydrophobic nano-ZnO (QS-ZnO) surface and 304SS surface at −5 °C, −10 °C and −15 °C. The icing time of CSS-ZnO surface was prolonged by about 2.7 h at −5 °C, delayed by about 40 min at −10 °C and delayed by about 9 min at −15 °C. The CSS-ZnO surface is the most effective surface in static anti-icing. It is because that there has a residual air layer at the solid-liquid interface and the coating can still effectively retard ice formation in a partially wetted state. In the dynamic icing test, compared with QS-ZnO surface, SS-ZnO surface and 304SS surface at −16 °C, SS-ZnO surface and QS-ZnO surface have no anti-icing effect, and CSS-ZnO surface has a significant anti-icing effect. The mechanism for inhibiting condensation of water droplets by superhydrophobic surfaces was illustrated, which can be identified that the contact angle of the ice embryo will increase with the increase of the water contact angle. This work provides a practical application for promoting anti-icing ability of 304SS surfaces in industry. [ABSTRACT FROM AUTHOR]

Icing/frosting poses a significant problem for materials used in everyday applications. In recent years, anti-icing methods utilizing superhydrophobic materials have become popular. These materials have superhydrophobic surfaces with air-solid composite structures, which can prevent icing/frosting by creating air cushions in the micro- and nano-scales of the rough structure. However, long-term protection of the substrate is challenging due to air leakage from the air cushion and the breakdown of the superhydrophobic coating. The use of superhydrophobic materials in cold environments is also greatly limited by this shortcoming. In this paper, superhydrophobic copper foam (SHS CF) was created by using electrochemical oxidation and impregnation techniques and subsequent modified by fluorosilane coupling agent on the copper foam surface to reduce surface particle activity through condensation reactions, achieving a superhydrophobicity with a water contact angle of up to 170±2°. Furthermore, gas was utilized to form a specific rough structure by combining with Cu(OH) 2 micro-nanopins, leading to the development of long-lasting gas in SHS CF (LAG-SHS CF). The LAG-SHS CF exhibited impressive anti-frost characteristics, with a delayed icing time of approximately 2171 s. Notably, the SHS CF retained strong wetting capabilities and excellent resistance to abrasion, UV, acid, and alkali even after the removal of LAG, which was ascribed to the fact that the composite structure effectively reduces the solid-liquid contact area and has a high roughness. These properties provide a solid foundation for the application of LAG-SHS CF. The findings of this study contribute to the creation of new materials with anti-icing and anti-frost properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Through the reasonable design of the microstructure of superhydrophobic coatings, the solid-liquid contact area between the substrate and the liquid can be reduced, the penetration of corrosive medium into the liquid can be reduced, and the flow resistance can be lowered. In this paper, a bionic superhydrophobic composite coating of aluminum matrix material was prepared by the spraying method using KH550 coupling agent-modified silica (KH550@SiO 2) and stearic acid-modified titanium dioxide (STA@TiO 2) mixed with waterborne polyurethane. The performance was tested by water contact angle, drag reduction measurements, and electrochemical analysis. The composite coating has a droplet contact angle of 163.4° and a rolling angle of 4° and is extremely wettable. The synergistic effect of the air layer and coating densities resulted in excellent corrosion inhibition efficiency of the coating in a 3.5 wt % NaCl solution. In addition, the composite-coated spheres can form a continuous air cavity during water ingress, which is essential for extending the drag reduction capability of the coating in liquids. The design and preparation of superhydrophobic composite coatings have promising applications in large-area corrosion protection and voyage damping of metals. [Display omitted] • Dual nanoparticle superhydrophobic coating. • Superhydrophobic surface, drag reduction, corrosion resistance. • Synergistic enhancement of drag reduction and corrosion protection in marine environments. • A facile method for constructing scalable and low-cost superhydrophobic coating with anti-corrosion and drag-reduction properties. [ABSTRACT FROM AUTHOR]

Given the increasing contamination of freshwater supplies, it is essential to effectively treat industrial wastewater. However, treating industrial wastewater using a single method is challenging due to the presence of complex contaminants like petroleum, organic dyes, bacteria, and other complex contaminants. In this study, we present a straightforward and scalable approach to prepare multifunctional nanocellulose-based membranes (NM) that exhibit superhydrophobicity, self-cleaning, oil/water separation, photocatalysis, and anti-bioadhesion properties. To begin with, we created NM by extruding fiber slurry onto a stencil and drying it. Next, we built a polyurethane (PU)/ZIF‐8/1H, 1H, 2H, 2H‐perfluorooctyltriethoxysilane (POTS)-based superhydrophobic layer by spraying it over the NM's surface. By employing the aforementioned processes, we successfully integrated multiple functions into a single superhydrophobic NM. Our results demonstrate that the NM-PU/ZIF-8/POTS membrane exhibits superior hydrophobicity performance, with a high-water contact angle (166.8 ± 0.8°) and a low rolling angle (5 ± 0.3°). Moreover, these samples retain high-water contact angles and low rolling angles even in harsh environments such as acid and alkali solutions, high temperatures, abrasion resistance, UV aging resistance, bending and folding, tape peeling, and self-cleaning. The NM-PU/ZIF-8/POTS membrane also exhibits high and stable oil-water separation performance, with a separation efficiency of 94.6% and a relatively high separation flux (133.2 L·m−2·h−1). At the same time, the NM-PU/ZIF-8/POTS membrane exhibits water-in-oil emulsion separation ability. The membrane's stability, effectiveness, and reusability were demonstrated through ten repetitions of degradation experiments using aqueous methylene blue solution, with the NM-PU/ZIF-8/POTS membrane exhibiting an excellent degradation rate (>94%). Finally, the bioadhesion resistance test indicated a reduction of 69.1% in the adhesion rate of the NM-PU/ZIF-8/POTS membrane. Overall, the creation of the NM-PU/ZIF-8/POTS membrane serves as a useful inspiration for the practical application of superhydrophobic NM in multifunctional integration, while also broadening the scope of membrane applications. [Display omitted] • A simple strategy to manufacturing multifunctional superhydrophobic NM-PU/ZIF-8/POTS membranes. • This membrane has high separation efficiency and flux for a variety of oils. • This membrane had outstanding anti-biofouling performance against Chlorella. • The degradation and anti-fouling tests proved its photocatalytic and self-cleaning performances. [ABSTRACT FROM AUTHOR]

The superhydrophobic coating blocks a certain air layer between the solid surface and the liquid, thereby changing the interaction between the surface and water, and has potential applications in enhancing buoyancy and drag reduction. Consequently, a superhydrophobic coating designed to reduce drag (the contact angle was up to 168°) was prepared in this study. The coating was applied to copper mesh by spraying a mixed solution comprising ZIF-8 particles, waterborne polyurethane, and a silane coupling agent, resulting in a significant enhancement of load capacity. The superhydrophobic coating can change the contact mode between the copper mesh and water, leading to a remarkable sevenfold increase in the maximum load capacity when compared with the uncoated sample, primarily due to its' increased buoyancy. In addition, the self-made superhydrophobic model ship exhibited an impressive drag reduction efficiency of up to 36 %, indicating that it has significant drag reduction capability. It's worth noting that once water enters, the superhydrophobic spheres will form a gas cavity, which is critical for the coating's drag reduction capability. The self-cleaning property of this superhydrophobic composite coating is highly promising. Moreover, it can also purify seawater by utilizing ZIF-8's photocatalytic activity to degrade organic contaminant. Therefore, in the context of actual ships and underwater vehicles, this superhydrophobic coating holds potential as a relevant strategy for enhancing buoyancy and reducing drag, thus offering commercial value. [Display omitted] • ZIF-8/POTS coatings were prepared by simple chemical modification and spraying technology. • The WCA and SA of the Zif-8/pots coating were 168 ± 1° and 4°, respectively. • The coating exhibits excellent self-cleaning and photocatalytic properties. • The coating exhibits excellent floating and drag reduction properties. [ABSTRACT FROM AUTHOR]

Superhydrophobic coatings have numerous applications across various industries. However, there have been limited reports on superhydrophobic and smart coatings that possess multifunctionality and their applications in flexible sensing electronics. Herein, a Robust fabrication of superhydrophobic and photocatalytic self-cleaning flexible strain sensor membrane (Nanocellulose-based membrane/Graphene/Co(OH) 2 /Stearic acid (NM-G-Co(OH) 2 -STA)) for full-range human motion was developed by burshing and dip-coating method. The synergistic effect and strong interaction of Co(OH) 2 , STA, and Graphene lead to the formation of a highly conductive hierarchical structure on the surface of NM. As a result, a sensor with excellent conductivity stability and superhydrophobicity is achieved. The water contact angle (WCA) of this sensor membrane can reach 166°. The integration of these characteristics allows the sensor to operate effectively in challenging conditions, including bending, abrasion, high temperature, UV exposure, and contact with corrosive liquids. This sensor membrane possesses excellent self-cleaning, photocatalytic, and full-range human motion. This sensor membrane results in high photocatalytic degradation capacity (> 93%) for dyed wasterwater treatment. This sensor membrane integrates high sensitivity (GF = 137.25), fast response and recovery (response time is 151.01 ms, recovery time is 123.01 ms) and dynamic durability in a single system (stretching and bending at 131.3 mm/min for 300 s). Due to its excellent flexibility, high sensitivity, and broad sensing range, this sensor membrane is suitable for use as a wearable sensor to detect various human motions, including wrist, finger, and knuckle movements. Consequently, this material holds significant potential for applications in wearable electronics, measurement platforms, rainfall monitoring, and intelligent irrigation systems. [Display omitted] • A flexible, superhydrophobic and conductive strain sensor membrane is prepared. • The Co(OH) 2 nanoparticles and STA improve the mechanical properties of strain sensor membrane. • The strain sensor membrane excellent corrosion resistance and durability. • The strain sensor membrane showed great photocatalytic degradation activity. • The strain sensor membrane based strain sensor can detect various body motions. [ABSTRACT FROM AUTHOR]

Bio-based membranes for removing organic dye and microorganism-containing complicated oil-water effluents simultaneously are sustainable, low-cost, renewable, biodegradable, and nontoxic. Here, a robust, sustainable and molecular-level superhydrophobic Pulp/cellulose nanofiber (CNF) composite membrane (SPCCM) via crosslinking of nanofibers and coating ZnO suspensions for accomplishing this purpose is proposed. The results show that this designed SPCCM has superior superhydrophobicity (water contact angle: 163 ± 2°) and superoleophilicity (oil contact angle: 0 °), which has a great separation efficiency for separating oil-water mixture (92 %) and a high flux (1435 L·m−2·h−1·bar−1). Moreover, SPCCM showed good durability in harsh environment (such as: bending, corrosion solution, temperature, etc). It also showed that the synergistic impact of electrostatic adsorption and ZnO photocatalyst is responsible for the high degradation capacity (Degradation under visible light using 300 w xenon lamp, high degradation efficiency up to 98 %). Furthermore, the SPCCM had a high level of anti-biofouling for microorganisms. Thus, the SPCCM mainly derived from sustainable pulp fibers showed potential performance for oil/water separation and water purification. [Display omitted] • A simple method has been developed to prepare Pulp/CNF composite membrane (CM). • ZnO can construct superhydrophobic coating on the CM surface. • The CM exhibits good mechanical and chemical robustness. • The CM possesses excellent self-cleaning ability. • The CM shows efficient emulsions' separation, photocatalytic degradation property. [ABSTRACT FROM AUTHOR]

A CM-MnO 2 -STA sample for oil/water separation, photocatalytic degradation and anti-biofouling property was obtained via MnO 2 micro/nano structure and subsequent modification of STA. This multifunction CM-MnO 2 -STA sample demonstrates great potentials in the field of wastewater treatment, oil spill cleanup, and anti-biofouling ability. [Display omitted] • A CM-MnO 2 -STA sample was obtained by MnO 2 micro/nano structure and STA. • This sample showed physical/chemical/mechanical stability in harsh environment. • This sample showed superior oil–water separation efficiency. • This sample showed great photocatalytic degradation activity. • This sample exhabited strong anti-biofouling adhesion potential. Flexible multiple functional cellulose-based membrane (CM) for oil/water separation, anti-microbial and photodegradation are in great demand in marine wastewater treatment due to its' effective and ecologically benign. Based on this requirement, MnO 2 micro/nanoparticles were in situ deposited on CM sample surface followed by decoration of stearic acid (STA) for very effective oil/water separation, anti-fouling, and dye photodegradation triggered by visible light. The results demonstrated that this as-prepared CM sample showed superhydrophobicity with a water contact angle of 162 ± 2° and superoleophilicity with an oil contact angle of 0°. It also demonstrated exceptional high stability in hostile environments (acid and alkali solution, high temperature, wear resistance, underwater writing, self-cleaning) and a 2.6% increase in tensile strength. In addition, it can successfully separate emulsified oils from typical oil-in-water emulsions with good separation efficiency all over 98% and comparatively high flux (145.8 L·m−2·h−1). After 8 cycles, the separation efficiency of the n-hexane/water emulsion is still over 98%. Moreover, over 98% of MB was degraded by using superhydrophobic CM sample, indicating strong photocatalytic activity. Meanwhile, in the maritime environment, this biomimetic sample decreased the adherence of green algae by more than 95%, demonstrating strong anti-biofouling adhesion potential. It indicates that this cost-effective, scalable, environmental friendly, and efficient methodology presented superhydrophobic CM sample has the potential to promote the widespread development of multipurpose superwetting materials, with enticing potential for the treatment of complex oily wastewater. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces have many advantages in wetting fields. However, the lack of easyily production methods and limited mechanical/chemical/physical robustness remain the two most pertinent barriers to the scalability, large-area production, and widespread use of superhydrophobic materials. In this work, a mechanical/chemical/physical robustness superhydrophobic coating sample consisting of a regular array of square Cu mesh with secondary nano structures of polytetrafluoroethylene (PTFE) and SiO 2 powders on the sidewalls is produced through a scalable and easyily production technique of the combination of hot-press sintering and subsquent spray-coating. The Cu mesh is used as a template to fabricate the grooves and bulges as the first-level roughness, and the SiO 2 powder is maintained on the surface of the coatings to form two-level hierarchical structures, with both micro and nano structures firmly affixed by low-surface energy polymer binder (PTFE). For comparison, Cu mesh and Cu mesh/Cu sample are also produced. Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and time-dependent apparent contact angle are used to examine the as-prepared materials. The corrosive solution, high temperature, UV irradiation, ultrasonic treatment, water drop hitting, sand drop impacting, multi-cycled sandpaper abrasion, tape-peeling test, and self-cleaning test was conducted to simulate the real-world damages. All of the armored superhydrophobic coating samples have an apparent water contact angle of more than 150°, as well as outstanding mechanical and chemical resilience. The salt spray test and mechanical behavior of the as-prepared samples revealed that the armored superhydrophobic coating sample has the lowest corrosion rate, the highest tensile strength, and the greatest elongation among these threee as-prepared samples, implying that it has the best anti-corrosion ability and mechanical property. This strategy might give guidance for the development of composite materials that need to retain mechanical/chemical/physical robustness in severe working conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

A superhydrophobicity cellulose membrane for high-efficiency oil/water separation and removal of hazardous organic pollutants was fabricated via depositing Fe 2 O 3 particles and subsequent modification of STA. This multifunction superhydrophobic cellulose membrane demonstrates great potentials in the field of oil-water separation field and photocatalytic property. [Display omitted] • A multifunction membrane was obtained by depositing Fe 2 O 3 particles and STA. • This membrane still show superhydrophobicity in harsh environment. • This membrane showed excellent oil-water separation ability. • This membrane exhibited great photocatalytic degradation activity. In this work, the fabrication and characterization of a multifunction cellulose membrane is reported: (і) high stable in harsh environment (acid/alkali solution, high temperature, abrasion, underwater writable, heat-insulated and self-cleaning), (іі) oil-water separation with high efficiency, and (ііі) effective and rapid photocatalytic degradation of hazardous environmental contaminants. This multifunction cellulose membrane was successfully prepared through depositing Fe 2 O 3 particles and subsequent modification of stearic acid (STA). The results showed that this multifunction cellulose membrane had excellent superhydrophobic and self-cleaning properties with a high static water contact angle of 167.2 ± 2°. Moreover, it possessed unusual repellent properties towards acid/alkali solution, abrasion, high temperature and heat-insulated properties. This membrane could also be used for writing underwater and keep satisfactory superhydrophobic performance for a long time with a water contact angle of 154.2 ± 2°. It also showed a high separation efficiency (>89.0 %) and a high separation flux (greater than 80 Lm−2 h−1) for these three oils (toluene, trichloromethane and n-Hexane). After repeated separation for 6 cycles, the separation flux and separation efficiency of n-Hexane has not changed significantly. It also demonstrated reliable photocatalytic ability, a useful property for resisting organic contaminations. Compared with conventional cellulose membrane, it is anticipated that this multifunction superhydrophobic cellulose membrane is not only really competitive in complex and harsh environment, but also demonstrates great potentials in the field of effective underwater treatment, fire-proof applications, oil-water separation field and photocatalytic property. [ABSTRACT FROM AUTHOR]