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There is significant interest in developing paints based on structural colors, which do not fade like dyes and pigments. To use these paints as coatings, it is necessary to have a technology that can easily impart structural color to the material's surface without changing color based on the viewing angle. In addition, water‐repellent properties that lead to stain resistance are required for practical application. This study applies a structural color coating by synthesizing hydrophobic melanin particles using the Michael addition reaction and arranging these particles on a substrate at high speed. The resulting coating film shows angle‐independent structural color due to the amorphous structure of the particle arrangement, and the color tone could be controlled by adjusting the particle size. The combination of the particle's hydrophobic surface and the microscopic unevenness from the arrangement structure produced a superhydrophobic coating with a contact angle of over 160°. Since the Lotus effect, resulting from superhydrophobic surfaces, can maintain the cleanliness of structural color coatings, the findings of this research will contribute to the development of next‐generation coating technology. [ABSTRACT FROM AUTHOR]

Polyimide composites are easily degraded in high temperature and high humidity environments for long service, which reduces their reliability and stability in aerospace, electronic components, weapons, and other fields. In this paper, the inorganic and organic multiphase double‐layer coating was prepared. The insulating layer was made of vinyl polysilazane resin as the base material and hollow glass microspheres as the filler. The hydrophobic layer consisted of polydimethylsiloxane as the base material, hollow phenolic microspheres, and nano‐TiO2 as the filler. The heat resistance, hydrophobic properties, and aging resistance of the coated polyimide resin matrix composites were studied. The results showed that the thickness of the double‐layer coating was about 200 μm. Under the 200°C thermal insulation test, the maximum temperature drop can be achieved at 59.7°C. After adding 5 wt% TiO2, the static contact angle of composites was increased from 86.2° to 127.7°. Significantly, the hydrophobic performance was improved by 48.1%, which was due to the construction of micro‐nano structures in the surface layer coating. In the accelerated hydrothermal aging tests, the bending properties of coated composite materials can be improved by 8.5%, 3.2%, and 8.7% in water, alkali, and acid environments, respectively. The moisture absorption of glass fiber and the pyrolysis of polyimide led to the degradation of the mechanical properties. The existence of heat‐resistant and hydrophobic coating could effectively eliminate this adverse effect, which was of great significance for polyimide composites to cope with various service environments. Highlights: A novel coating consisting of thermal insulating and hydrophobic layers was developed on glass fiber reinforced polyimide composites (G/PI) composites.The maximum temperature drop of coating can be achieved at 59.7°C.The static contact angle of coated G/PI composites was increased from 86.2° to 127.7°.In the aging tests, the protective effect of the coating resulted in improved mechanical strengths of G/PI composites.The microscopic damage morphology was performed to analyze the anti‐aging properties of the coating. [ABSTRACT FROM AUTHOR]

Fuel cell systems are potential power sources for transportation applications due to their high energy efficiency, rapid start-up, and low emissions. The bipolar plates, which constitute the major volume of the fuel cell stack, are usually made of graphite. However, the brittle nature of graphite plates makes them unable to resist shock or vibration; as a result, metallic plates are considered as bipolar plates in fuel cell stacks due to their resistance to impact, strength, and cost-effective manufacturing. However, surface corrosion and hydrophobicity are significant challenges that need to be overcome in the fuel cell working environment. In this study, the resistance of SS304 plates to the electrochemical environment is enhanced by coating them with TiN, while the hydrophobic surface of the stainless steel is induced using femtosecond lasers and vacuum treatments. The effects of treatment conditions on surface morphology, contact angle, interfacial resistance, and fuel cell performance are investigated. Results show that linearly polarized lasers with scanning speeds of 20 mm s−1 and 80 mm s−1 are the optimum treatments for SS304 and TiN-coated SS304 plates, respectively. The TiN coating greatly improves the performance of SS304 flow field plates, with a maximum power density of 0.9 W cm−2 compared to 0.44 W cm−2 without the coating. Fuel cells consisting of laser-processed TiN-coated SS304 flow field plates can also operate durably with hydrogen and oxygen at the anode and cathode, respectively. [Display omitted] • Superhydrophobic surface of SS304 plates is created by femtosecond laser treatment. • A scanning speed of 80 mm s−1 is suitable for 3–5 μm thin TiN-coated SS304. • Four hours of vacuum-treated laser-processed SS304 exhibits a contact angle of 152.6°. • Fuel cell exhibits a high stability with maximum power density of 0.9 W cm−2. [ABSTRACT FROM AUTHOR]

Gallium‐based liquid metals with outstanding electrical conductivity and fluidity are widely used in wearable electronics for wireless communication, human–machine interaction, and smart textiles. However, their fluidity makes them easily leak from the embedded conductive circuits under repeatable stretching, mechanical damage, or exposure to acidic and alkaline environments, limiting their reliability in practical use. Here, highly stable LM–polymer composites are shown with the ability to endure significant mechanical or chemical stresses, maintaining low resistance changes (R/R0 = 3.3 and 2.4) after 10 times of standard washing and 24 h of storage in corrosive solutions. The use of fluoropolymer, providing robust interfacial binding with the gallium oxide layer, effectively serves as a barrier layer to withstand mechanical and chemical damage through the synergistic effect of adaptive dipole–dipole interactions among composites and enhanced hydrophobicity. The as‐prepared composites can be readily hot pressed onto commercial fabrics to develop electronic textiles with outstanding conductivity (10214 S m−1), high air permeability (148.6 mm s−1), and moisture permeability (30.3 g m−2). Taking advantage of their excellent stability and permeability, e‐textiles are demonstrated as washable thermal therapy patches and skin‐interfaced electrodes for epidermal biopotential recording. [ABSTRACT FROM AUTHOR]

Cotton fiber fabric with practicability and functionality attracts much attention and plays an important role in many occasions. However, its surface contains many hydroxyl groups to show a hydrophilicity, leading to easy adhesion to stains to limit the application. In this work, polyglycidyl methacrylate (PGMA) was used as an oily and flexible matrix and graphene oxide (GO) particles were used as a filler. PGMA/GO composite modified fabrics with hydrophobicity, self-cleaning feature and wear resistance were prepared by constructing surface coatings. Compared with original fabric, PGMA/GO composite modified fabric has a surface hydrophobicity attributed to organic oily characteristic of PGMA, and high surface roughness from GO surface enrichment. The reasonable GO content (1 wt%) in composite coating makes the modified fabric exhibit the best overall performance (surface water contact angle of ~ 151.7°; chromatism of ~ 2.4; large water contact angle of ~ 140.2° after 200 surface wear cycles). This work provides an effective method for an industrial production of high-performance waterproof cotton garment fabrics. [ABSTRACT FROM AUTHOR]

In this study, a three-dimensional (3D) porous sponge capable of oil–water separation was fabricated using recycled expanded polystyrene (EPS) through 3D electrospinning, by adding phosphoric acid to the electrospinning solution. The fabrication process was a rapid and efficient single-step process to produce the 3D sponge. In addition, the additive's concentration was also optimized for oil absorption. The fabricated EPS sponge was highly effective in oil–water separation due to its excellent hydrophobic and oleophilic properties. This demonstrates its potential as a sustainable and efficient absorbent to address ongoing oil pollution issues. Moreover, the performance of the recycled EPS sponge was found to be comparable to that of sponges made from virgin polystyrene, suggesting the feasibility of using recycled materials for the production of high-value products. This research presents an efficient method for fabricating 3D sponges from recycled materials, contributing to environmental protection and resource recycling. [ABSTRACT FROM AUTHOR]

Monitoring potassium ion (K+) concentration is essential in veterinary medicine, particularly for preventing hypokalemia in dairy cows, which can severely impact their health and productivity. While traditional laboratory methods like atomic absorption spectrometry are accurate, they are also time-consuming and require complex sample preparation. Ion-selective electrodes (ISEs) provide an alternative that is faster and more suitable for field measurements, but their performance is often compromised under variable temperature conditions, leading to inaccuracies. To address this, we developed a novel screen-printed ion-selective electrode (SPE) with hydrophobic Ti3C2 Mxene and gold nanoparticles (AuNPs), integrated with a temperature sensor. This design improves stability and accuracy across fluctuating temperatures by preventing water layer formation and enhancing conductivity. The sensor was validated across temperatures from 5 °C to 45 °C, achieving a linear detection range of 10−⁵ to 10−1 M and a response time of approximately 15 s. It also demonstrated excellent repeatability, selectivity, and stability, making it a robust tool for K+ monitoring in complex environments. This advancement could lead to broader applications in other temperature-sensitive analytical fields. [ABSTRACT FROM AUTHOR]

Non-Newtonian viscous fluids such as yogurt, honey, etc., due to their extremely high viscosity and complex fluidity, remain on food containers after use, where adhesion and staining occurs, which is a great inconvenience and causes a lot of wasted resources. Hydrophobic coatings can be an excellent candidate for eliminating liquid waste. Inexpensive wollastonite nanoparticles were used to build rough micro- and nano-structures, and chitosan was used to emulsify rice bran wax to prepare green and low surface energy emulsions. The above two were mechanically mixed to obtain the hydrophobic emulsion, and coated on the paper surface and heat-treated to prepare the hydrophobic paper. Contact angles up to 157.3°. The coating exhibits good self-cleaning properties for a wide range of non-Newtonian viscous food liquids and shows excellent resistance to repeated machine bending and multiple abrasion damages, while maintaining its hydrophobicity. After 40 cycles of friction, the contact angle is 148.1°, which is still close to 150° and has good hydrophobicity. In addition, the coating has great potential for application to the interior surfaces of various food packages to reduce or even eliminate liquid food residues. [ABSTRACT FROM AUTHOR]

Bio inspired textured surfaces are used in diversified engineering applications namely in tribology, biomedical, antifouling, anti-icing, micro fluidics, anti-bacterial surfaces, solar cells, etc. These textured surfaces are categorized as dimpled textured surfaces (negative) or pillared (positive) textured surfaces. Presently, laser machining is used to create dimpled textured surfaces. However very limited number of micro manufacturing process are available which can fabricate positive textured surface consisting of pillars of varying cross-sectional areas. Therefore, the primary objective of this work is to explore the reverse micro EDM process (R-MEDM) to fabricate pillared (positive) textured surface even on metallic surface. Earlier studies in R-MEDM had reported challenges involved in preparation of electrode used in the process. It is very difficult to machine thousands of micro-holes on plate which act as electrode in R-MEDM process. These holes will be replicated on work surface during processing. The work presented here addressed solutions to the challenges of preparation of electrodes and improves the process by using modified bubble assisted flushing method. Detail experimental investigation has been carried out in this work to evaluate the effect of process parameters on material removal rate, explore the use of low-cost sieves as electrodes followed by contact angle measurement on a fabricated textured surface. It is found that sieves are low-cost solution to successfully fabricate hydrophobic textured surface. Passing bubble enhances the debris flushing efficiency. Improvement of material removal rate by 20–25% and contact angle by 15–18% is realized using a bubble flushing method. The array of square rods of 200 µm side and 250 µm lengths were successfully fabricated on 6 mm bulk rod of brass with a good dimensional accuracy. [ABSTRACT FROM AUTHOR]

Distinctive challenges in developing oleophilic/hydrophobic membranes through the coating technique for the separation of oil–water mixtures are the lengthy processes, the release of volatile contents, and the decrease in separation efficacy with repeated cycles. In this work, an attempt has been made to develop cost-effective, eco-friendly, bio-based, sustainable, and durable hydrophobic/oleophilic polybenzoxazine (PBZ) matrices coated on the cotton fabric for efficacious separation of oil–water emulsion mixtures. The benzoxazine monomers were synthesized using eugenol, furfuryl amine or stearyl amine, and paraformaldehyde (E-fa and E-sa) by a solvent-less, green synthetic approach. The synthesized benzoxazine monomers were characterized by FTIR and 1H NMR. Trifunctional benzoxazine monomers were synthesized by a simple thiol-ene click reaction using E-fa, E-sa, and trithiocyanuric acid. Later, the hydrophobic cotton fabric or filter paper was prepared by a simple dip coating method using E-fa, E-sa, E-fa/TCA, and E-sa/TCA separately, followed by thermal curing. The hydrophobic PBZ coated on the fabric/filter paper materials revealed better separation of emulsified oil–water mixtures with a separation efficacy of > 98% even after 15 repeated cycles. The thermal behavior of developed PBZ showed better thermal stability (thermal degradation and higher char yield) than conventional bisphenol A and F based PBZs. The hydrophobic/oleophilic surface on the cotton fabrics/filter paper, altered with the sustainable bio-based eugenol-based benzoxazines, is eco-friendly and easy to scale up, revealing prodigious capacities in several practical applications including oil–water separation and self-cleaning. [ABSTRACT FROM AUTHOR]

In recent years, the interest in structured hydrophobic surfaces has considerably grown, finding applications in many industrial fields, including aerospace, automotive, and biomedical. Three‐dimensional (3D) printing technology is a simple, rapid, and economic process to fabricate structured surfaces based on neat polymers and composite materials, allowing working with a wide variety of plastic materials. The manufactured surfaces show a roughness depending on the printing design and the printing resolution: this characteristic is ideal to achieve superhydrophobic properties. Furthermore, patterned surface structures can be printed by fused filament fabrication (FFF), so increasing the hydrophobic character of the samples; indeed, micro‐ and nanosurface structures are required to make a hydrophobic surface. In this study, 3D micropatterned textures of pillars were printed by FFF using polylactide (PLA) and polypropylene (PP) as polymer filaments and PLA/carbon nanotubes (PLA/CNTs) and PP/carbon fibers (PP/CF) as composite filaments. Morphologies of printed specimens were analyzed by optical microscopy and scanning electron microscopy. Good correspondence was found between pillar dimensions and edge‐edge pillars distance of computer aided design (CAD) and composites 3D‐printed samples. Their wettability was evaluated by static contact angle (CA) measurements. Results clearly show a significant increase of water CA values up to 50% in all micropatterned samples with respect to flat surfaces. This improvement was achieved by surface microstructuring without the use of nanoparticles and/or chemical treatment. [ABSTRACT FROM AUTHOR]

Collecting urine samples from cats is a significant challenge for veterinarians due to their instinctive behavior to bury waste. The introduction of superhydrophobic cat soil, which prevents urine absorption, offers an innovative solution. This not only simplifies the diagnostic process for veterinarians but also significantly reduces stress for pets and their owners. In this study, we synthesized a hydrophobic coating using zinc oxide/silica composite nanoparticles (ZnO/SiO2 CNPs) modified with perfluorodecyltrichlorosilane (FDTS) compounds for various surfaces such as soil, sand, stone, and glass. Tetraethoxysilane (TEOS) and zinc acetate dihydrate were used as precursors, while FDTS was employed for surface modification. The prepared ZnO/SiO2 composite sol was sprayed onto different coatings, and the resulting hydrophobicity was confirmed by water contact angles, with an average angle of 110.3° for cat soil. Structural and morphological features of the synthesized ZnO/SiO2 CNPs were analyzed using XRD, FTIR, EDX, and FESEM techniques. The chemical resistance of the coated stone was tested in acidic and neutral environments, showing better hydrophobicity in the neutral condition. The study highlights the potential of this composite to enhance agricultural practices in arid regions, facilitate pet urine collection in veterinary medicine, and offer various environmental benefits. [ABSTRACT FROM AUTHOR]

Oils and lipids help make water-insoluble drugs soluble by dispersing them in an aqueous medium with the help of a surfactant and enabling their absorption across the gut barrier. The emergence of microemulsions (thermodynamically stable), nanoemulsions (kinetically stable), and self-emulsifying drug delivery systems added unique characteristics that make them suitable for prolonged storage and controlled release. In the 1990s, solid-phase lipids were introduced to reduce drug leakage from nanoparticles and prolong drug release. Manipulating the structure of emulsions and solid lipid nanoparticles has enabled multifunctional nanoparticles and the loading of therapeutic macromolecules such as proteins, nucleic acid, vaccines, etc. Phospholipids and surfactants with a well-defined polar head and carbon chain have been used to prepare bilayer vesicles known as liposomes and niosomes, respectively. The increasing knowledge of targeting ligands and external factors to gain control over pharmacokinetics and the ever-increasing number of synthetic lipids are expected to make lipid nanoparticles and vesicular systems a preferred choice for the encapsulation and targeted delivery of therapeutic agents. This review discusses different lipids and oil-based nanoparticulate systems for the delivery of water-insoluble drugs. The salient features of each system are highlighted, and special emphasis is given to studies that compare them. [ABSTRACT FROM AUTHOR]

The acrylic polymer composites in this study are made up of various weight ratios of cement or silica nanoparticles (1, 3, 5, and 10 wt%) using the casting method. The effects of doping ratio/type on mechanical, dielectric, thermal, and hydrophobic properties were investigated. Acrylic polymer composites containing 5 wt% cement or silica nanoparticles had the lowest abrasion wear rates and the highest shore-D hardness and impact strength. The increase in the inclusion of cement or silica nanoparticles enhanced surface roughness, water contact angle (WCA), and thermal insulation. Acrylic/cement composites demonstrated higher mechanical, electrical, and thermal insulation properties than acrylic/silica composites because of their lower particle size and their low thermal/electrical conductivity. Furthermore, to improve the surface hydrophobic characteristics of acrylic composites, the surface was treated with a dielectric barrier discharge (DBD) plasma jet. The DBD plasma jet treatment significantly enhanced the hydrophobicity of acrylic polymer composites. For example, the WCA of acrylic composites containing 5 wt% silica or cement nanoparticles increased from 35.3° to 55° and 44.7° to 73°, respectively, by plasma treatment performed at an Ar flow rate of 5 L/min and for an exposure interval of 25 s. The DBD plasma jet treatment is an excellent and inexpensive technique for improving the hydrophobic properties of acrylic polymer composites. These findings offer important perspectives on the development of materials coating for technical applications. [ABSTRACT FROM AUTHOR]

The carbon dioxide emissions caused by heat transfer have become one of the largest sources of carbon dioxide emissions. Reducing greenhouse gas emissions caused by heat conduction have become an urgent problem to be solved. In this paper, we are committed to the preparation and evaluation of the properties of the wood-based oxidized cellulose microtube thermal insulation foam materials inspired by natural microtubule insulation structure. The oxidized cellulose microtube can be uniformly dispersed in water due to the introduction of active carboxyl functional groups. The introduction of active carboxyl functional groups can improve the flexibility and dispersibility of the oxidized cellulose microtubules in water. The oxidized cellulose microtube (HOCM-X) foam can be prepared through strong electrostatic force between Ca2 + and carboxylic acid groups and MTMS surface hydrophobic treatment. The property of the wood-based oxidized cellulose microtube thermal insulation foam materials can be effectively tuned by the concentration of the oxidized cellulose microtubule. The water contact angle of the HOCM-X foam was about 135°. As the oxidized cellulose microtubules content increases, the mechanical strength of the HOCM-X foam gradually increases. The HOCM-2.5 foam exhibits the best thermal insulation properties with the thermal conductivity as low as 47 mW·m−1·k−1. [ABSTRACT FROM AUTHOR]

In this study, we present a method to enhance the hydrophobic properties of organofluorosilicon styrene–acrylate emulsions while simultaneously reducing their environmental pollutional, and assess their potential for applications in oil–water separation materials, waterproof coatings, and related fields. We achieved this by developing organofluorosilicon styrene–acrylate emulsions with core–shell interpenetration properties through a meticulously designed preemulsified semicontinuous seed emulsion polymerization process. In addition, we have added sodium lignosulfonate, a green and renewable material, to the polymerization process to further enhance the environmental sustainability of these emulsions. A comprehensive characterization of the lignin-modified emulsions was conducted using various techniques, including assessments of storage stability, centrifugal stability, ionic stability, water contact angle, thermogravimetric analysis, Fourier transform infrared spectroscopy, as well as scanning and transmission electron microscopy analyses. The findings revealed that the lignin-modified emulsions exhibited similar stability to conventional phenylpropylene emulsions in terms of Ca2+, mechanical, and storage stability, while demonstrating notably enhanced thermal stability and hydrophobicity. Significantly, immersion of filter paper in the modified emulsion resulted in filter paper with markedly improved hydrophobic properties, while retaining surface pores and preserving filter capacity. This underscores the potential of lignin-modified emulsions for application in oil–water separation materials. Furthermore, this innovation led to a noteworthy 50% reduction in the usage of organofluorosilicone monomers, thereby mitigating potential hazards and environmental pollution associated with their use. Our utilization of sodium lignosulfonate as a modifier for organofluorosilicon styrene–acrylate emulsions represents a novel and promising approach for applications in oil–water separation and waterproof coatings. The integration of green and sustainable materials has significantly advanced environmentally friendly solutions, fostering more eco-conscious practices in industrial and commercial applications. [ABSTRACT FROM AUTHOR]

Dust deposition on photovoltaic systems has a significant impact on the transmittance, temperature, and roughness, causing reductions in their power generation efficiency and lifetime. A promising approach to deal with this problem relies on the use of superhydrophobic coatings to impart the surfaces of these devices with self-cleaning properties. In this work, materials with different chemistry and morphology were added to an acrylic dispersion to create hydrophobic surfaces using a non-fluorinated coating simple strategy for glass substrates. Results showed that materials with more complex morphology, namely the spherical shape of silica nanoparticles, and the needle-like and prism-like structures of zinc oxide, imparted the glass with higher water contact angles. All coatings prepared displayed self-cleaning features and good adhesion to the glass substrate. Coatings comprising silica nanoparticles, zirconia and alumina modified with HDMTS were the best ones to prevent ice formation. In terms of chemical stability, all the coatings resisted acidic conditions close to acid rain pH and solvents with mild polarity. Therefore, the coatings proposed hold great potential to expel dust contaminants and prevent ice formation of photovoltaic devices, increasing their lifetime and power generation efficiency. [ABSTRACT FROM AUTHOR]

Poly (lactic acid) (PLA) membrane is fabricated through electrospinning, which effectively absorbs oil from the oil/water mixture. The prepared PLA electrospun membrane is hydrophobic with a water contact angle (WCA) of 117.2⁰. Introduction of POSS (polyhedral oligomeric silsesquioxane) particles as nanofiller into the PLA matrix, as well as a coating on the electrospun membrane, appreciably enhances the hydrophobicity and thermal stability of the nanofibrous membranes. The membranes become dense, less porous, and crystalline after heat treatment. The unannealed nanofibrous membrane with a highly porous, oleophilic surface helps to impart higher oil absorption properties than that of annealed membranes, which are 60.45 g/g and 66.03 g/g for palm oil and used engine oil respectively. The as-prepared PLA fibrous membranes can absorb oil from the oil-water interface, showing excellent recyclability and separation efficiency > 70%. [ABSTRACT FROM AUTHOR]

Plastic agricultural films are widely applied in agriculture due to the integrated functionalities such as insulation, increasing air moisture, and preserving soil moisture. However, the massive consumption of petroleum-based plastic agricultural films has caused serious environmental problems. Therefore, in the pursuit of the green agriculture, the development of biodegradable alternative films is an emerging need for the future of agriculture. This paper presents a general strategy for the preparation of transparent biodegradable cellulose-based films with good hydrophobicity and thermal insulation properties using lignocellulosic nanofibers (LCNF), copper nanowires (CuNWs), and polydimethylsiloxane (PDMS) as the main raw materials. The results indicate that CuNWs are uniformly deposited on LCNF and both sides are covered by PDMS (LCNF/CuNW/PDMS), exhibiting tensile properties equivalent to ordinary polyethylene film, with tensile strength and elongation at break significantly increased to 113.34 MP and 6.54%, respectively. Due to the excellent infrared radiation properties of CuNWs, infrared images reveal that the temperature difference between the composite film and the heat source is 5.2 °C, reducing heat transfer to outside and providing a warm and comfortable interior for crops. In addition, the hydrophobicity (water contact angle > 90°) and water vapor barrier properties (0.0289 g cm−2 d−1) of the composite are improved by PDMS modification of the surface, overcoming the defects of the cellulose substrate performance and greatly raising the possibility of its application. Based on the above properties, this study provides a facile strategy to prepare flexible cellulose-based composite films with infrared insulation and water resistance, to be valuable for improving the growing environment of crops, and promising to replace petroleum-based plastic films with great potential for agricultural applications. [ABSTRACT FROM AUTHOR]

Enhancing the hydrophobicity of chitosan through acylation enables the encapsulation of water‐insoluble drugs within the polymeric carrier cores. In this study, hydrophobically modified chitosan was synthesized by reacting low‐molecular‐weight chitosan with acyl chloride (C18–C24) using an agitation method under mild conditions. The structure of acylated chitosan was analyzed using FTIR and 1H‐NMR spectroscopy. The degree of substitution (DS) varied between 56% and 69% for different long‐chain N‐acylated chitosan, with N‐stearoyl chitosan (ChC18) exhibiting the highest DS. The incorporation of capecitabine (CAP) into extended acylated chitosan increased particle size and decreased zeta potential. N‐lignoceroyl chitosan (ChC24) exhibited the highest zeta potential value of −27 mV for 0.2 mg of CAP, indicating that the most extended acyl group was the most stable in the suspension. Transmission electron microscope images revealed that all acylated chitosan particles were spherical, with sizes ranging from 100 to 200 nm, and existed as stand‐alone entities, indicating excellent stability in suspension. The loading of CAP increased in particle size but did not alter particle shape, except for ChC24, which exhibited agglomeration. SEM images revealed that the individual arrangement of particles in CAP‐ChC18 made it more stable than other acylated chitosan. In contrast, the formation of clusters in CAP‐ChC24 can be attributed to strong hydrophobic interactions. X‐ray photoelectron spectroscopy results show that there is no nitrogen atom in ChC18, which means that the acyl group is oriented inward and bound to the stearoyl group via van der Waals forces. At different drug weight‐to‐carrier ratios, the encapsulation efficiency (EE) of CAP with varying acyl group lengths ranged from 85% to 97%. The drug loading (DL) capacity and EE increased as the amount of drug in the carrier increased. However, the length of the acyl group did not significantly affect DL and EE, even when the carrier‐to‐drug ratio was consistently maintained. Sustained release was observed in CAP‐loaded ChC24, indicating a significant influence of the extended chain on chitosan. Consequently, extended N‐acylated chitosan possesses enormous potential as a drug delivery system for CAP. [ABSTRACT FROM AUTHOR]

In situ electrospun 3D polyacrylonitrile (PAN) nanofiber-reinforced (EPNR) silica aerogel monoliths were prepared through methyltriethoxysilane–trimethylchlorosilane modification followed by ambient pressure drying (APD). The 3D PAN nanofiber network was built into silica sol by liquid-assisted collection. Homodispersed and intertwined PAN nanofibers were well incorporated into the silica aerogel matrix. The APD-EPNR silica aerogel had a porosity of 90.9% and a BJH pore volume of 2.15 cm3 g−1. Furthermore, the APD-EPNR silica aerogel monolith showed excellent flexibility and revealed a highly hydrophobic surface with a water contact angle of 145º. The APD-EPNR aerogel was suitable for removal of oil from water. The static mass of the APD-EPNR silica aerogel achieved 700%–1500% to various solvents and the aerogel can be recovered without obvious performance decline. The APD-EPNR silica aerogel mat also achieved oil/water separation with a separation efficiency of more than 99%. Hence, the prepared APD-EPNR silica aerogel has promising application for treatment of oil pollution. [ABSTRACT FROM AUTHOR]

Abstract Cotton fiber fabric with practicability and functionality attracts much attention and plays an important role in many occasions. However, its surface contains many hydroxyl groups to show a hydrophilicity, leading to easy adhesion to stains to limit the application. In this work, polyglycidyl methacrylate (PGMA) was used as an oily and flexible matrix and graphene oxide (GO) particles were used as a filler. PGMA/GO composite modified fabrics with hydrophobicity, self-cleaning feature and wear resistance were prepared by constructing surface coatings. Compared with original fabric, PGMA/GO composite modified fabric has a surface hydrophobicity attributed to organic oily characteristic of PGMA, and high surface roughness from GO surface enrichment. The reasonable GO content (1 wt%) in composite coating makes the modified fabric exhibit the best overall performance (surface water contact angle of ~ 151.7°; chromatism of ~ 2.4; large water contact angle of ~ 140.2° after 200 surface wear cycles). This work provides an effective method for an industrial production of high-performance waterproof cotton garment fabrics.

This research involved top-down dealumination and steam treatment methods to design the hierarchical pores of ZSM-5, which is then wet-impregnated with a Fe-Co. This method overcomes the steric barrier that hinders the oxidative desulfurization (ODS) process and makes the catalyst hydrophobic, thereby allowing it to overcome the biphasic hindrance caused by the difference in polarity between the fuel oil and the oxidant. Characterization of the catalyst's properties based on BET and BJH, XRF, and contact angle, as well as testing its performance on DBT model oil in n-hexadecane and Indonesian commercial diesel were conducted. Simulation of the reaction energy profile using density functional theory calculations was also carried out to deepen insight into the mechanism of the reaction. Results of this study show that the catalyst has excellent catalytic reactivity in the long-chain hydrocarbon ODS process, with a TOF number of 183 h−1.

[Display omitted] • A direct-to-metal (DTM) coating was prepared with long-lasting anti-corrosion performance. • The synergistic effect of dopamine methacrylate and fluorine compounds on corrosion protection was studied. • PUA coatings had great water-repellency, anti-contamination, and transparency properties based on NP-GLIDE structures. Aluminum and its alloys have been widely used in our lives. However, Aluminum and its alloys is prone to corrosion, especially in harsh environment. In recent years, hydrophobic coatings were used in the corrosion protection of metal. But, the low surface tension of resins made them have a worse wettability on metal which had high surface tension, resulting in a worse adhesion of these coatings. Herein, we developed a long-lasting anti-corrosion direct-to-metal polyurethane NP-Glide coating based on the coordination effect of polyphenol and dual cross-linking. In comparative evaluation, the corrosion protection and anti-contamination performances of direct-to-metal polyurethane NP-Glide coating are significantly improved by the introduction of functional monomer dopamine methacrylamide (DMA) and TEMAc-8. The PU coatings with 10 wt% TEMAc-8 possesses high impedance value (|Z| 0.01Hz > 109 Ω•cm2) after 40 days of immersion in 3.5 wt% NaCl solution, exhibiting a great pull-off adhesion both in dry and wet coating, and a long-term anti-corrosion performance for aluminum alloy protection. [ABSTRACT FROM AUTHOR]

The membrane contactor application to purify acid gases is a significant advancement in environmental protection and engineering processes. Notwithstanding the numerous privileges of membrane contactors, the wetting of the polymeric membrane is considered the main worry in developing the mentioned technology. The polymeric membrane wetting by liquid absorbents increases the membrane mass transfer resistance and decreases the gas absorption. In this study, hydrophobic PVC membranes including various amounts of CaCO3 nanoparticles were manufactured to reduce the wetting problem. The prepared membranes were evaluated using AFM, TEM, XRD, contact angle, SEM, and tensile strength measurements. The contact angle results illustrated that adding the nanoparticles enhanced the membrane contact angle; so that for nanocomposite membranes comprising 1.5 wt.% nanoparticles, the contact angle increased from about 77°–94°. Investigating the tensile strength results showed that the nanoparticle presence in the membrane structure raised the tensile strength by 10 MPa. Finally, the nanocomposite and pure membrane performance in CO2 absorption was evaluated in the system of membrane contactors. The findings exhibited that after 25 days of the gas absorption process, the permeate flux of pure membranes significantly decreased. However, the gas absorption flux in nanocomposite membranes containing 1.5 wt.% nanoparticles remained constant during this period. [ABSTRACT FROM AUTHOR]

Abstract Boric acid and other impurities on the surface of boron (B) particles can interact with hydroxyl-terminated polybutadiene (HTPB), weakening the mechanical properties and energy release efficiency of boron-based solid rocket propellants. SA@B composite particles were created by coating stearic acid (SA) on the surface of B particles through solvent evaporation-induced self-assembly. The study investigated the impact of SA coating on the combustion performance of B particles and the mechanical properties of HTPB matrix composites. The results showed that the SA coating enhanced the oxidation efficiency of B particles in air. The combustion heat of SA@B composite particles is 30.29 MJ/g, about 50% higher than that of B particles. During the combustion of SA@B composite particles, fewer molten solid particles surround the flame, which enhances the stability of the combustion process of the B particles. Furthermore, the SA coating effectively enhanced the dispersion of B particles in HTPB. At a stretching speed of 100 mm/min, the tensile strength of the SA@B/HTPB composite materials is higher than that of the B/HTPB composite materials. Moreover, when the mass loading of the SA@B composite particles reaches 50 wt%, the tensile strength of SA@B/HTPB composite materials is 2.46 MPa. Activating the surface of boron particles with SA can significantly improve their compatibility with HTPB, which is crucial for the stable storage of boron-based solid rocket propellants.

High heat generation is the main problem that sophisticated electronic devices can suffer. The pool boiling process can offer an excellent heat dispassion at constant temperatures. Therefore, it is one of the most powerful cooling processes used in nuclear power plants, data centers, air conditioning, etc. Because of that, enhancing pool boiling has become a goal of many recent investigations. The current paper presents an experimental study to evaluate the effect of nano and nanocomposite coating on the performance of pool boiling of deionized water under atmospheric pressure. Four surfaces made of copper were used in this study: smooth, CNT (1 g), GNPs (1 g), and (CNT-GNPs (1:1) g) surfaces. A four-step electro-deposition method was used to fabricate a nickel coating using the abovementioned materials. The variation in coating materials offers different surface wettability and roughness to the fabricated surfaces. The experiment's outcome revealed that the hydrophilic material can enhance the critical heat flux (CHF). The mixed wettability obtained by the nanocomposite coating can improve the heat transfer coefficient (HTC). Maximum enhancement in the CHF is obtained by GNPs (1 g) surface with 102%, while the maximum HTC is obtained by (CNT-GNPs (1:1) g) surface with 154% when it is compared with the plain surface.

In this work, a simple and one-step process was demonstrated to develop hydrophobic polymer surfaces. Commercially available polycarbonate (PC) was treated to turn the front surface hydrophobic with an average wetting contact angle (WCA) as high as 110.5°. The formation of micro-flowers with a coverage density of 9.29 × 106/cm2 on the top of fine base nanostructures was confirmed by a high-resolution field emission scanning electron microscope (FESEM). Impact of typical metal and metal oxide such as silver (Ag) and tungsten oxide (WO3) deposited on such hydrophobic surfaces was demonstrated. Petals of micro-flowers and fine base nanostructures were well decorated with functional metals such as Ag and thus the front surface remained hydrophobic with an average WCA as high as 106.6°. Abundant sharp spikes on the top of narrow hills and dips as revealed in the high-resolution FESEM investigation, were speculated to be the reason behind this hydrophobic characteristic. On the other hand, the hydrophobic surface (WCA of ∼ 110.5°) turned hydrophilic (WCA of ∼11.7°) when the surface was decorated with functional metal oxides, such as WO3. Sessile drop tests were carried out to record average WCA and to understand the wetting characteristics of the specimens. A plausible mechanism for such hydrophobic characteristics as well as the transition from a hydrophobic state to a hydrophilic state has been elucidated.

Abstract Ferro hydrophobic particles possess essential properties for controlling the behavior of suspended substances in water. By adjusting the concentration of these particles, the magnetic force within the fluid carrier can be modified, leading to the emergence of distinct flow structures and patterns on the water's surface. This study examines the cloaking phenomenon exhibited by different ferroparticle conditions, employing both experimental and numerical approaches. Under the magnetic influence, hydrophilic particles can attain cloaking velocities of up to 35 mm/s, while hydrophobic particles remain unaffected by the magnetic force, remaining suspended on the water's surface. Hydrophobization of ferroparticles not only decreases their water-cloaking ability but also alters their magnetic properties. The inherent hydrophobic nature of these particles enhances water surface stability, rendering them valuable in various applications, including biomedical and self-cleaning technologies. This research holds particular significance for manipulating suspended particles in water, particularly in biomedical applications like drug delivery and tissue engineering, as well as for advancing self-cleaning technologies.

Moth eye protuberances, for instance, exhibit highly developed and well-organized nanostructures that allow them to adapt to a wide range of environmental conditions and achieve remarkable antireflective performance, which has inspired and been emulated by scientific advancement. Innovative studies have focused on bioinspired and imitating moth-eye patterns to provide a textured surface in multilayer antireflective coatings (ARC) using nanomaterials, polymers, or composites to eliminate undesired reflection in standard optical components and optoelectronic industrial applications. Multilayer AR systems provide a number of advantages over single-layer designs. Still, their limited applicability is due to obstacles such as mismatched properties at interfaces, high costs, poor mechanical durability, and wetting concerns. Using MgF2 and polytetrafluoroethylene, we develop a technique for fabricating high-performance AR nanostructures on borosilicate crown glass and Fluorine-doped Tin Oxide substrates via the glancing angle deposition technique. By inducing porosity and changing the deposition angle (α) at 550 nm, the refractive index of MgF2 is reduced from 1.38 to 1.14. In agreement with optical modelling predictions, high-performance ARC has been successfully produced on different substrates. Besides this, introducing a thin layer of polytetrafluoroethylene on MgF2 ARC via vapor deposition having a refractive index of 1.21 deposited at α ∼80° results in inducing water-repellent properties in ARC. Hence, our fabricated ARC yields stable AR efficiency with outstanding directional uniformity, durability, and negative temperature stability, having hydrophobic characteristics.

Phenolic aerogels based on resorcinol‐formaldehyde (RF) are among the best thermally insulating materials. However, the hydrophilicity inherent to the free phenolic moiety of RF gels generally limits their actual range of applications. Prior efforts to render phenolic gels hydrophobic are restricted to post‐synthetic functionalizations of hydrophilic gels, processes that are often limited in efficiency, scope, and/or longevity. Here, an acid‐mediated conversion of 1,3,5‐trimethoxybenzene with formaldehyde is reported, yielding monolithic trimethoxybenzene‐formaldehyde (TMBF) aerogels and xerogels with low density (0.11–0.30 g cm−3), high porosity (74–92 %), inner surface areas (SBET) of up to 284 m2 g−1, and thermal conductivity of 34.5–43.9 mW m−1 K−1. For a monolithic xerogel based on TMBF xerogels an unprecedently low thermal conductivity of 34.5 mW m−1 K−1 could be achieved. In addition, all TMBF gels are thermally stable (degradation >280‐310 °C) and highly hydrophobic (water contact angles 130°–156°). As such, TMBF serves as a new class of inherently hydrophobic aerogels and xerogels and useful complement to RF materials. [ABSTRACT FROM AUTHOR]

Hydrophobic antifouling polymers capable of self‐healing performance are highly desirable for industrial applications. However, the construction of self‐healing, hydrophobic antifouling polymers is challenging considering their complex fouling environments, which are humid in aqueous environment. In this work, a self‐healing hydrophobic polymer containing Fe3+‐catechol coordination applicable to antifouling is synthesized. The hydrophobic fluoroalkyl segments in the polymers formed unique domains dispersed in a polydimethylsiloxane matrix. The as‐synthesized polymers can completely restore their tensile strength, and their self‐healing efficiency is above 90% in both artificial seawater and pure water because of the dynamic Fe3+‐catechol coordination interactions. The as‐synthesized polymer exhibited self‐healing and antifouling properties against common marine bacteria. The colony adhesion and self‐healing processes of the damaged coating in artificial seawater containing marine bacteria are characterized by laser confocal microscopy. This strategy may be useful for the development of future polymeric antifouling materials. [ABSTRACT FROM AUTHOR]

Boric acid and other impurities on the surface of boron (B) particles can interact with hydroxyl-terminated polybutadiene (HTPB), weakening the mechanical properties and energy release efficiency of boron-based solid rocket propellants. SA@B composite particles were created by coating stearic acid (SA) on the surface of B particles through solvent evaporation-induced self-assembly. The study investigated the impact of SA coating on the combustion performance of B particles and the mechanical properties of HTPB matrix composites. The results showed that the SA coating enhanced the oxidation efficiency of B particles in air. The combustion heat of SA@B composite particles is 30.29 MJ/g, about 50% higher than that of B particles. During the combustion of SA@B composite particles, fewer molten solid particles surround the flame, which enhances the stability of the combustion process of the B particles. Furthermore, the SA coating effectively enhanced the dispersion of B particles in HTPB. At a stretching speed of 100 mm/min, the tensile strength of the SA@B/HTPB composite materials is higher than that of the B/HTPB composite materials. Moreover, when the mass loading of the SA@B composite particles reaches 50 wt%, the tensile strength of SA@B/HTPB composite materials is 2.46 MPa. Activating the surface of boron particles with SA can significantly improve their compatibility with HTPB, which is crucial for the stable storage of boron-based solid rocket propellants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Silica with hydrophobic hyperbranched structure was obtained. • Excellent defoaming and antifoaming effects were obtained in PDMS. • Hyperbranched microstructure exhibit superior "needle effect". • The "interface − coordination" defoaming mechanism is proposed. Hydrophobic nano silica powder is a kind of important synergist to silicone defoaming agents. The large pore volume and branched chain conformation of silica nanoparticles present superior effects on defoaming properties. However, silica nanoparticles synthesized by liquid phase easily aggregate and pore collapse because of their high surface activity and polarity, leading to poorer dispersity and limited practicability. In this paper, a novel hydrophobic silica with a hyperbranched structure was designed through in-situ modifying method with hexamethyldisilazane (HMDS) and polydimethylsiloxane (PDMS) in the liquid phase. The trimethylsilanol generated by HMDS hydrolysis reacts quickly with the highly active hydroxyl groups on the silica, causing the surface properties of the nanoparticles to transform from polar to non-polar properties. The steric hindrance of the trimethyl silicon and the reduction of the surface polarity effectively prevent silica pores from collapsing and maintain the macropore structures to realize the hyperbranched silica. At the same time, the −Si (CH 3) 2 − from PDMS endowed the hyperbranched silica with excellent hydrophobicity. When applied in the defoaming agent, the hydrophobicity of silica contributes to dewetting the foams, and the hyperbranched spatial structures play an enhanced needling effect. Therefore, this hydrophobic hyperbranched silica exhibited a surprising defoaming effect, which significantly reduced the defoaming time from 464.4 s to less than 2 s, superior to commercial defoaming silica (155.3 s). The defoaming efficiency reached 100 % within 2 s of the end of the shaking, and the defoamer antifoaming ability was improved to reach 27.5 min, which was 77 % higher than that of commercial defoamer. [ABSTRACT FROM AUTHOR]

In recent years, wearable smart textiles with multifunctional properties have attracted great interest for use with a wide range of applications, including personal protection, sport, healthcare etc. In the present study, all-in-one multifunctional conductive hydrophobic coated cotton fabric with electromagnetic interference (EMI) shielding, joule heating, and antibacterial properties was prepared via in-situ chemical oxidative polymerization. A graphene oxide (GO)–polyaniline (PANI)–silver (Ag) composite was coated onto the cotton fabric, exhibiting a low electrical resistance of 24.3 Ω sq−1 and strong hydrophobicity, with a water contact angle of ~ 139°. The high electrical conductivity of the composite coating resulted in excellent EMI shielding of ~ 52 dB in the X-band frequency region. Notably, the EMI shielding performance was tunable by simply changing the pH due to the acid- and alkali-sensitive nature of PANI. Furthermore, the fabricated conductive cotton fabric demonstrated excellent joule heating, achieving a temperature of 105.7 °C within 30 s at a voltage of 3.5 V. Additionally, in the presence of Ag, the cotton fabric exhibited excellent anti-bacterial properties against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. [ABSTRACT FROM AUTHOR]

AbstractLocalized corrosion in steel heat exchangers is a major concern, occurring mostly during operational shutdowns. Due to the absence of flow and moisture content availability, corrosion reduces operation efficiency. A study aimed to optimize the proportions of Zinc and Chromium (Zn-Cr) for developing a hybrid multi-layer electroplating method to inhibit corrosion in hypo-eutectoid carbon steel commonly used in heat exchangers. The Zn-Cr coating was performed using the amperometric method in an electrochemical workstation, producing coatings of varying thicknesses by varying the potential and time. The surface morphology was characterized using Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) analysis. The average thickness of the Zn-Cr coating was found to be 2.5 µm using the scanning probe microscope analysis. The corrosive action of a standard 3.5% NaCl solution was investigated on both coated and uncoated specimens through open circuit potential measurement and electrochemical impedance spectroscopy. The results indicated that the Zn-Cr coating effectively resisted corrosion. Contact angle measurement of water particles with the Zn-Cr coated specimen revealed a near-super hydrophobic nature with the highest contact angle of 146.8°. [ABSTRACT FROM AUTHOR]

2,4-Difluoronitrobenzene has been reacted with a linker diamine (ethylenediamine or propylenediamine) and butylamine, in either order, to give new molecular building blocks for porous supramolecular networks. Two structures were established by X-ray single crystal structure determinations. The propylenediamine structure displays small pores, which may be due to the longer and more flexible linker in the structure. [ABSTRACT FROM AUTHOR]

This study employed atmospheric plasma (AP) pretreatment to enhance the hydrophobicity of polytetrafluoroethylene (PTFE) thin films. When a PTFE thin film was deposited on the substrate pretreated with AP, the deposition followed the Frank-van der Merwe mode at hydrophilic regions and the Volmer–Weber mode at hydrophobic regions, thereby causing the PTFE thin film to have continuous bumps. In accordance with the Wenzel and Cassie equation, increasing the surface roughness of hydrophobic materials increased their hydrophobicity. The water contact angle increased from 100° to 110° after deposited PTFE thin film on substrate pretreated with AP. Finally, the water contact angle further increased to 115° after annealed in nitrogen gas. A salt spray test demonstrated that the hydrophobic PTFE thin film had excellent corrosion resistance and stability. This hydrophobic film preparation technology can be used for the protective film of electronic device, sensor, solar cell and so on. [ABSTRACT FROM AUTHOR]

The effect of biphilic surfaces on subcooled flow boiling in a horizontal rectangular duct was investigated. Biphilic surfaces were created on an aluminum alloy substrate in the form of juxtaposed Hydrophobic (HPo) and Hydrophilic (HPi) transverse strips. In this regard, two different testing samples with strip widths of 10 and 18 mm were prepared, named pattern I and pattern II, respectively. Using Deionized Water (DIW), the experiments were performed with the two mentioned biphilic patterns and a plain surface. Finally, different cases were compared, and the results were interpreted. The results showed that the biphilic surfaces improve the Heat Transfer Coefficient (HTC) and cause boiling to be initiated at a lower wall temperature. In this regard, pattern I and pattern II represent 22 and 40% improvement in HTC, and boiling initiates 31 and 33.5 °C sooner compared to the plain surface, respectively. In addition, the experiments were also conducted with an Ethylene Glycol/Water mixture (EG/W) in the same manner. The results revealed that EG/W represents smaller HTC values for all cases and shifts the boiling points to higher wall temperatures compared to DIW. It is worth mentioning that the major amount of this HTC reduction is occurred in the single-phase area, in lower wall temperatures. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to fabricate the acrylic-based polymeric composite coating with a hydrophobic surface associated with natural oil polyol (NOP) and polydimethylsiloxane with the incorporation of 3 Wt.% SiO2 nanoparticle (SiO2np) against the corrosive NaCl media. Design/methodology/approach: The structural properties of the formulated polymeric composite coatings were investigated by using Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, water contact angle (WCA) and cross-hatch (X-Hatch) tests. The WCA measurement was used to study the surface wettability of the formulated polymeric composite coatings. The corrosion protection performance of the nanocomposite coated on the mild steel substrate was studied by immersing the samples in 3.5 Wt.% NaCl solution for 30 days using electrochemical impedance spectroscopy. Findings: The enhanced polymeric composite coating system performed with an excellent increase in the WCA up to 111.1° which is good hydrophobic nature and very high coating resistance in the range of 1010 Ω attributed to the superiority of SiO2np. Originality/value: The incorporation of SiO2np into the polymeric coating could enhance the surface roughness and hydrophobic properties that could increase corrosion protection. This approach is a novel attempt of using NOP along with the addition of SiO2np. [ABSTRACT FROM AUTHOR]

Inorganic semiconductor gas sensors, being widely utilized in gas‐sensing applications, face significant challenges in attaining mechanical flexibility and humidity resistance in wearable sensing fields. Herein, a highly flexible, breathable, and hydrophobic all‐inorganic self‐supporting nanofiber (NF) gas sensor is developed using electrospinning combined with thermal sulfidation approach. This innovative sensor features a bilayer configuration, with an amorphous SiO2 nanofiber substrate layer and an interwoven SiO2 and SnO2–SnS2 nanofiber active layer. The relatively low elastic modulus of the amorphous SiO2 nanofibers, combined with the three‐dimensional network interwoven structure, endow the SnO2–SnS2–SiO2/SiO2 sensor with superior mechanical flexibility. The sensor exhibits excellent sensitivity, selectivity, moisture resistance, and cycling stability (>10 000 cycles at 140° bending) to both high and low concentration NO2. Notably, an excellent flexible detecting capability of the sensor to NO2, an asthma‐related biomarker, is demonstrated at ultralow concentrations (≈25 ppb) in simulated exhaled breath environments. The enhanced moisture resistance is attributed to the effective inhibition of hydrogen bond formation from H2O molecules by the Sn─S bonds formed through sulfidation of SnO2 nanofibers. This work represents a substantial advancement in the universal fabrication of flexible, breathable and moisture‐resistant inorganic semiconductor sensors for wearable breath sensing applications. [ABSTRACT FROM AUTHOR]

Non-ionic hydrophobic eutectic solvents have emerged as a new class of eutectic solvents. They are prepared by mixing two non-ionic components. They have gained significant interest compared to their counterpart ionic hydrophobic eutectic solvents and hydrophobic ionic liquids due to the availability of a wide array of non-ionic substances that can be used to prepare these solvents. Understanding the distinct physical characteristics of these solvents is crucial to their practical application within process industries and associated fields. The present work reports the development of a density model for these solvents based on the conductor-like screening model (COSMO), a dielectric continuum solvation model. For this purpose, a comprehensive literature search was carried out, and 485 density points of 37 different hydrophobic non-ionic eutectic solvents were collected. COSMO volume, one of the outputs of the COSMO calculations, was correlated with the experimental molar volume for the model development. Two different models were developed, one at 298.15 K and another a general model that can predict the density over a wide temperature range at atmospheric pressure. The developed model only requires the molar ratio and COSMO volumes of the components forming the eutectic solvents to predict the density. The proposed general model performed better than most other models and was comparable with the best one reported in the literature, with an average relative deviation percent (ARD%) of 1.34%. [ABSTRACT FROM AUTHOR]

Tremendous potential in the field of anti-biofouling coatings to prevent stainless steel (SS)-based underwater pipelines, sea vessels and other marine structures have been recognized to protect from biofouling, which is often initiated by algae attachment over the surface. In this work, hydrophobicity in spray-pyrolysed tungsten oxide (TO) coating on SS-316 substrate has been reported for the first time, via post-processing treatment using octadecyltrimethoxysilane (ODTMS) to induce self-assembled monolayer (SAM). Initially, structural and vibrational characteristics of ODTMS and ODTMS-treated TO (OTO) coating on SS were analysed using X-ray diffraction (XRD), Fourier transform infrared (FTIR) and Raman spectroscopies. OTO-coating depicted a water contact angle (WCA) of 121°, revealing its hydrophobic nature, with further affirmation from X-ray photoelectron spectroscopy (XPS). Durability of the TO-coating was explored using the scratch hardness (Hs) test at different loading conditions (5, 10 and 15 N). Biofouling study was conducted by culturing blue-green algae (BGA, Phormidium sp.) in an in-house laboratory setup for 40 days, using seawater (collected from the Arabian Sea, Karnataka). The SS, TO- and OTO-coatings were immersed for 14 days in a controlled sea-water environment in the laboratory with the presence of BGA. A comparative study on the areal-algae attachment was keenly analysed over SS-, TO- and OTO-coatings. This work can be projected as a promising application providing multi-dimensional solutions in creating scratch-resistant and anti-biofouling coatings on SS in the shipbuilding industry. [ABSTRACT FROM AUTHOR]

In this study, superhydrophobic surfaces were fabricated on aluminium alloy plates with two different experimental procedures using the dip coating method. Each procedure was optimised using the Taguchi design to evaluate the significance of factors such as SiC abrasive paper number, etching time, and chemical modification time. By determining three levels for these factors, the L9 orthogonal array was formed. Water contact angle (WCA) measurements determined the wettability of the surfaces against the water. Scanning Electron Microscopy (SEM) was used to assess the general appearance and roughness of the surfaces. The coating thickness of the surfaces was also measured. For both experimental procedures, the most effective parameter in providing superhydrophobic coatings on the surfaces was determined as the etching time. SEM analyses demonstrated the roughness created by the clustered and protruding structures formed on the surface after the coating. The WCAs above 150° indicate that superhydrophobic surfaces were prepared. [ABSTRACT FROM AUTHOR]

Molecular sieving is an ideal separation mechanism, but controlling pore size, restricting framework flexibility, and avoiding strong adsorption are all very challenging. Here, we report a flexible adsorbent showing molecular sieving at ambient temperature and high pressure, even under high humidity. While typical guest‐induced transformations are observed, a high transition pressure of 16.6 atm is observed for C2H4 at 298 K because of very weak C2H4 adsorption (~16 kJ mol−1). Also, C2H6 is completely excluded below the pore‐opening pressure of 7.7 atm, giving single‐component selectivity of ca. 300. Quantitative high‐pressure column breakthrough experiments using 1 : 1 C2H4/C2H6 mixtures at 10 atm as input confirm molecular sieving with C2H4 adsorption of 0.73 mmol g−1 or 32 cm3(STP) cm−3 and negligible C2H6 adsorption of 0.001(2) mmol g−1, and the adsorbent can be completely regenerated by inert gas purging. Furthermore, it is highly hydrophobic with negligible water adsorption, and the C2H4/C2H6 separation performance is unaffected at high humidity. [ABSTRACT FROM AUTHOR]

In addition to filtering some sediments, hydrophobic wood sponges can also absorb many organic solvents, particularly crude oil. The leakage of crude oil poses a serious threat to the marine ecosystem, and oil mixed with water also generates great danger for its use. From the perspective of low cost and high performance, wood sponges exhibit great potential for dealing with crude oil pollution. Wood sponge is a renewable material. With a highly oriented layered structure and a highly compressible three-dimensional porous frame, wood sponges are extremely hydrophobic, making them ideal for oil–water separation. Currently, the most common approach for creating wood sponge is to first destroy the wood cell wall to obtain a porous-oriented layered structure and then enhance the oil–water separation ability via superhydrophobic treatment. Wood sponge prepared using various experimental methods and different natural woods exhibits distinctive properties in regards to robustness, compressibility, fatigue resistance, and oil absorption ability. As an aerogel material, wood sponge offers multi-action (absorption, filtration) and reusable oil–water separation functions. This paper introduces the advantages of the use of wood sponge for oil–water separation. The physical and chemical properties of wood sponge and its mechanism of adsorbing crude oil are explained. The synthesis method and the properties are discussed. Finally, the use of wood sponge is summarized and prospected. [ABSTRACT FROM AUTHOR]

Hydrophobic and oleophilic carbon fiber aerogel (CFA) was produced from lignocellulosic biomass such as black locust, hybrid polar, and chestnut shell. The biomasses were treated by some chemicals to prepare hydrophilic cellulose aerogel (CA). Successive freeze-shaping in liquid nitrogen (− 196 °C) and freeze-drying at − 53 °C and 0.113 mbar formed the hydrophilic cellulose aerogel (CA). Then, carbonization of CA at 900 °C yielded ultralight (0.011 g/cm3) and mesopore-rich (38 nm) hydrophobic/oleophilic CFA with moderate surface area (110–533 m2/g) and pore volumes (0.25–0.73 cm3/g). Water contact angle, surface functionalities, cellulose crystallinity, morphology, surface area, and thermal stability of CFA were characterized. Water contact angle of CFA reached 141° that indicates highly hydrophobic nature. Although no chemical activation was applied, the oil sorption capacities of 76.0, 81.6, and 81.8 g/g were achieved for diesel oil, crude oil, and sunflower oil, respectively. [ABSTRACT FROM AUTHOR]