Superwetting Surfaces Research Articles

Robust photopolymerized superoleophobic/superhydrophilic mesh for oil-water separation

Selective superwetting surfaces preserve the opposite superwetting properties of oil and water and have attracted considerable attention for their application in oil-water separation owing to their efficient surface energy since 2000. Among these surfaces, superoleophobic/superhydrophilic surfaces are considered remarkable because of their anti-oil properties. The coexistence of superoleophobicity and superhydrophilicity poses a challenge based on the traditional surface/interface theory. However, the fabrication of superoleophobic surfaces requires extremely low surface energy, which is achieved by introducing compounds with long fluorocarbon chains. However, these compounds are harmful to the environment. Herein, a mesh with superoleophobic/superhydrophilic properties was developed by coating a chemically etched copper mesh substrate with photopolymerized short fluorocarbon chains and water-insoluble hydrophilic monomers. This mesh can separate different types of oil-water mixtures with a separation efficiency of >99 %. The mesh demonstrated excellent underwater stability as well as chemical and mechanical durability. The water resistance and chemical durability of the mesh are stronger than those of the control copper mesh using metal ions and long fluorocarbon chains. Moreover, oil-water separation was achieved even after immersion in deionized water and salt, acid, and alkali solutions. In addition, the mesh preserves the ability of oil-water separation after being cleaned and reused for 10 times. The proposed superoleophobic/superhydrophilic mesh offers a solution for continuous oil-water separation and has prospects for developing anti-fouling/sweat-absorbing fabrics and self-cleaning surfaces.

Hydrogel Coated Mesh with Controlled Flux for Oil/Water Separation.

Superwetting surfaces are often applied in oil/water separation. Hydrogels have been widely prepared as superhydrophilic/underwater superoleophobic materials for oil/water separation since they are naturally hydrophilic. Hydrogels usually need to be combined with porous substrates such as stainless steel mesh (SSM) due to their poor mechanical properties. However, it is usually inevitable that the pores of the substrate are clogged during the actual preparation process, leading to a significant decrease in the flux, which limits its effective application. In this study, acrylic acid (AA), chitosan (CS) and modified silica were utilized to form a layer of dual-network PAA/CS@SiO2 hydrogel by photopolymerization on SSM, followed by a simple and novel ultrasonic-assisted pore-making method to generate numerous pores in situ on the surface of the hydrogel-coated mesh, which led to an increase in water flux from 0 to 70,000 L m-2 h-1 without decreasing the separation efficiency. After 100 separations of a mixture of n-hexane and water, the flux was still higher than 50,000 L m-2 h-1 with a separation efficiency above 99%, which is superior to most of hydrogel-coated meshes reported so far. Moreover, the prepared PAA/CS@SiO2 hydrogel-coated mesh also has good environmental stability, low swelling, and self-cleaning properties. We believe that the strategy of this study will provide a simple new perspective when hydrogels block the substrate pores, resulting in low water flux.

Anti-fouling ampholytic polymer membrane with super-wetting surfaces for efficient oil-water emulsion separation

The development of highly efficient polymeric membranes with super-wetting surfaces (superhydrophilic/submerged superoleophobic) is one of the ideal options to achieve emulsified oily wastewater separation. However, this remains a challenging due to low fluxes and severe membrane contamination limitations. Here, we have demonstrated an ultra-hydrophilic, underwater super-oleophobic, highly anti-fouling and antibacterial (polydopamine/poly [2-(methacryloyloxy) ethyl] dimethyl- (3-sulfopropyl) ammonium hydroxide) PDA/PSBMA modified membrane by grafting amphoteric polymers via atom transfer radical polymerization (ATRP). Benefiting from PSBMA's superhydrophilicity and the unique adhesion of dopamine (DA), the PDA/PSBMA modified membrane shows superhydrophilic properties, superoleophobicity underwater, oil resistance, and fouling resistance. Meanwhile, PDA/PSBMA modified membrane reached a superb permeability to water as high as 5620 L·m−2·h−1·bar−1 and remarkable oil rejection rate of 98 % in separating diesel-in-water emulsions. Furthermore, the separating performance remained fairly constant over 10 emulsion filtration cycles. Besides, the PDA/PSBMA modified membranes have excellent acid and alkali resistance and antibacterial properties, showing its potential for oily wastewater purification. This work offers a simple and versatile strategy to fabricate superwetting efficient polymeric membranes to separate emulsified oily wastewater.

Nano-Structural Superwetting Surfaces for Highly Reliable On-Site Detection of Bisphenol A.

In the domain of big data geographic screening for environmental pollutants, the expeditious dissemination of testing results to environmental investigation professionals is pivotal in facilitating comprehensive analysis and the implementation of more efficacious strategies for managing environmental issues. However, this endeavor can prove to be particularly arduous when conducting examinations in remote, resource-scarce rural areas and field environments, where deficient infrastructure often emerges as the principal impediment to unimpeded environmental monitoring. Therefore, the development of a reliable and portable monitoring strategy with the ability to analyze large amounts of data is highly required. Here, a deep-learning (DL)-assisted portable sensing strategy was developed based on thermal and pH dual-responsive nano-structural superwetting surfaces, for highly reliable, quick, and field monitoring of environmental pollutants. In our experiment, bisphenol A (BPA) was selected as the representative pollute. The achieved limit of detection, attaining a remarkably low value of 1.05 μM, unequivocally adhered to stringent international testing standards for evaluating the migration of BPA in thermal paper. Based on a DL image classification algorithm, highly precise predictions regarding the migration of BPA concentration were achieved, with an accuracy rate exceeding 99%. Furthermore, it successfully facilitated automated and exceedingly reliable monitoring of the migration of BPA from thermal paper within the principal provinces of thermal paper production in China. This strategy engenders the potential to establish correlations between environmental pollutant concentrations in specific regions and the prevalence of certain human ailments.

PDMS/magnetic lignin sponge for oil/water separation

Recyclable, non-toxic, and degradable biological substrates contribute significantly to super-wetting surfaces. In this work, we prepared magnetic micro-nano super-hydrophobic surfaces through a robust solution with magnetic modified lignin particles as the supporting structure. A novel PDMS (polydimethylsiloxane)/magnetic lignin particle (lignin@Fe3O4)/PDA sponge composite was fabricated. Through dopamine (DA) self-polymerization, covalent deposition of magnetic lignin (ML), and PDMS silane modification, the magnetic super-hydrophobic polyurethane sponge composite (Sponge-P) was synthesized so that the Fe3O4 nanoscale microspheres wrapped with microscale lignin magnetic particles adhered to the sponge surface tighter and were barely dislodged. The as-prepared Sponge-P displayed excellent flexibility and a water contact angle of up to 152.2°. The super-hydrophobic sponge prepared with the proposed method was acid-base stable (pH = 2–12), self-cleaning, and suitable for high-salinity seawater. The magnetic super-hydrophobic sponge has good oil-water separation ability and can absorb 43 times its own weight of oil. In the meantime, due to the introduction of magnetic materials into lignin, we not only constructed micro-nanostructures to improve the surface super-hydrophobicity, but also made Sponge-P have the function of magnetic recovery, which has a unique advantage in treating oily wastewater.

Influence of bio-inspired surface texture of additively manufactured 17-4 PH stainless steel adherends on the strength of adhesively bonded joints

The bonding potential of as-printed additively manufactured stainless steel is largely unknown, and the use of additional hierarchical bio-inspired surface texture has not yet been explored or characterized. In this study, it is demonstrated with the use of Selective Laser Melting (SLM) that a hierarchy of three surface features at different length scales can greatly improve the shear strength of metal-metal adhesive joints. The intrinsic stochastic texture of the SLM as-printed surface showed a high contact angle and a mixed failure with a dominance of adhesive failure. However, enhancing the as-printed surface with the Tree Frog (TF) and Fish Scale (FS) bio-inspired textures produced super-wetting surfaces, significantly improving the shear strength due to the synergistic effect of mechanical interlocking and physical adsorption adhesion mechanisms, resulting in mixed failure. The results indicated that the interfacial bonding performance was in line with the super-wetting behavior and was higher for the samples with a hierarchy of three surface features. The highest increase in bond strength was found for the tree frog hierarchical hexagonal texture (+70% compared to the as-printed texture). In contrast, abrasion of the as-printed surface with P1000-grit paper significantly reduced the surface roughness and increased the water contact angle, resulting in the lowest shear strength.

Ultraviolet modificated hydrophobic glass on-demand hydrophobic/superhydrophilic patterned surface for fog harvesting and underwater oil resistance

Atmospheric water collection provides a new solution to overcome the issue of water shortage. Learning from the smart creatures, biomimetic materials with the ability of fog harvesting have been development based on the surface wettability. Herein, a hydrophobic glass with high transparency could be fabricated to mimic the wettability patterns on the back of Stenocara beetle, by combining with different patterned masks and ultraviolet (UV) treatment method. The water collection rate of hydrophobic/superhydrophilic patterned glass has been optimized by changing and combining the size of superhydrophilic patterns on the hydrophobic surface, as well as the percent of superhydrophilic area. Comparing with uniform superwetting surfaces, the fog harvesting efficiency of fabricated patterned surface has been improved. The surface with smaller superhydrophilic pattern size and larger percent of superhydrophilic pattern area exhibits a higher fog harvesting efficiency. In the other hand, the hydrophobic glass could be modified to be superhydrophilic/underwater superoleophobic without mask under UV treatment, which has the ability of acid and alkali resistance.

Janus Fabric with Asymmetric Wettability for Switchable Emulsion Separation and Controllable Droplets with Low Friction.

Superwetting surfaces have recently attracted extensive attention in oil-water emulsion separation and droplet manipulations, which are widely used in various situations ranging from wastewater treatment, to flexible electronics, to biochemical diagnosis. However, it still remains challenging to obtain asymmetric materials with high efficiency during oil-water separation. Meanwhile, excellent robustness of the superhydrophobic surface is of significance but retards the mobility of droplets due to increased lateral adhesion of small spacing between solid protrusions. Herein, a facile approach is demonstrated to obtain the excellent robustness of Janus fabrics with asymmetric wettability. As for one side of water-in-oil emulsion separation, mimicking the soft earthworm with periodically wrinkled skin, an adaptive superhydrophobic fabric was fabricated by wrapping soft wrinkled poly(dimethylsiloxane) (PDMS) polymer with a cross-linking structure on woven fabric fibers induced by Ar plasma treatment. In addition, inspired by the desert beetle's structure but with reversed wettability, the other side of the Janus fabric was constructed for treating emulsion of oil-in-water. In addition, the underwater superoleophobic surface consisting of magnetically responsive PDMS microcilia with slippery heads, which shows robustness against pH, improved water drop mobility and lowered the resistance of fluid friction similar to the intrinsic hydrophobic Salvinia molesta with additional slippery performance. Hence, we propose a novel and easy approach that optimizes enhanced emulsion separation and reduced fluid drag properties simultaneously, which actively broadens their widespread applications.

Super-Slippery Poly(Dimethylsiloxane) Brush Surfaces: From Fabrication to Practical Application.

Superwetting surfaces with special slippery performances have been the focus of practical applications and basic research for decades. Compared to superhydrophobic/superoleophobic and slippery liquid-infused porous surfaces (SLIPS), liquid-like covalently attached poly(dimethylsiloxane) (PDMS) brush surfaces have no trouble in constructing the micro/nanostructure and the loss of infused lubricant, meanwhile, it can also provide lots of new advantages, such as smooth, transparent, pressure- and temperature-resistant, and low contact angle hysteresis (CAH) to diverse liquids. This paper focuses on the relationship between the wetting performance and practical functional application of PDMS brush surfaces. Recent progress of the preparation of PDMS brush surfaces and their super-slippery performances, with a special focus on diverse functional applications were summarized. Finally, perspectives on future research directions are also discussed.

Interfacial design for detection of a few molecules.

Major advances in molecular detection are being driven by goals associated with the development of methods that are amenable to miniaturization and automation, and that have high sensitivity and low interference. The new detection methods are confronted by many interfacial issues, which when properly addressed can lead to improved performance. One interfacial property, special wettability, can facilitate precise delivery and local enrichment of molecules to sensing elements. This review summarizes applications of unique features of special wettability in molecular detection including (1) chemical and electrochemical reactions in anchored microdroplets on superwetting surfaces, (2) enrichment of analytes and active materials at low contact areas between droplets and superwetting surfaces, (3) complete opposite affinities of superwetting surfaces toward nonpolar/polar solutes and oil/water phases, and (4) directional droplet transportation on asymmetric superwetting surfaces. The challenges and opportunities that exist in design and applications of special wettability in interfacial delivery and enrichment for detection of a few molecules are also discussed.

Magnetically controlled super-wetting surface switching between ultra-low and ultra-high droplet adhesion

Controlled liquid adhesion behaviors on super-wetting surfaces have gained significant attention, however, precise controlling of adhesion behavior is extremely hard to realize due to some inherent limitation in surface chemistry or morphology. Herein, we report a silicone-oil-infused magnetic porous polydimethylsiloxane (SMPP) surface with magnetically tunable super-wetting behaviors. Benefiting from the magnetic-field-responsive structure and interconnected porous characteristics, the SMPP can use magnetic field to control the seepage and absorption of silicone oil in the micropore channels, thereby precisely changing the adhesion of the water droplets on the surface. Compared to conventional super-wetting surfaces, this SMPP surface displays reversible in-situ conversion from ultra-high to ultra-low droplet adhesion with sliding angles ranging from 3° to 180° that hold up well even after severe cutting or abrasion. We also demonstrated that this tunable adhesion behavior can be used not only to enhance droplet manipulation in spatiotemporal but also to design unique microfluidic microreactors and antigravity transport devices. We envision that this proof-in-concept surface can serve as an important component of integrated control systems for intelligent manipulators, biochemical reactions, fluid transport, and biomedical analysis.

Self-Healing Superwetting Surfaces, Their Fabrications, and Properties.

The research on superwetting surfaces with a self-healing function against various damages has progressed rapidly in the recent decade. They are expected to be an effective approach to increasing the durability and application robustness of superwetting materials. Various methods and material systems have been developed to prepare self-healing superwetting surfaces, some of which mimic natural superwetting surfaces. However, they still face challenges, such as being workable only for specific damages, external stimulation to trigger the healing process, and poor self-healing ability in the water, marine, or biological systems. There is a lack of fundamental understanding as well. This article comprehensively reviews self-healing superwetting surfaces, including their fabrication strategies, essential rules for materials design, and self-healing properties. Self-healing triggered by different external stimuli is summarized. The potential applications of self-healing superwetting surfaces are highlighted. This article consists of four main sections: (1) the functional surfaces with various superwetting properties, (2) natural self-healing superwetting surfaces (i.e., plants, insects, and creatures) and their healing mechanism, (3) recent research development in various self-healing superwetting surfaces, their preparation, wetting properties in the air or liquid media, and healing mechanism, and (4) the prospects including existing challenges, our views and potential solutions to the challenges, and future research directions.

Design of a simple nanoscale hydrophilic-hydrophobic heterojunction system with under-liquid dual superlyophobicity for application in controllable droplet-based microreactor system and oil/water emulsions separation

Recently, many superwetting materials have emerged to deal with environmental problems. Among them, the under-liquid dual superlyophobic superwetting surface has attracted widespread attention due to the possessing of underwater superoleophobicity and underoil superhydrophobicity at the same time, and without the requirement of any energy stimulation when compared to conventional or responsive superwetting surfaces. However, A rational design of this deliciated surface state still lacking. Herein, a novel dual superlyophobic surface was achieved by simply modulating the relative proportion of a nanoscale hydrophilic-hydrophobic heterojunction system - cellulose nanofibrils (CNFs) and graphited multiwalled carbon nanotubes (gMWCNTs), and without any additional chemical modification. Besides, the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory or extended-DLVO (EDLVO) theory was introduced first to help understand the wettability variation of such a heterogeneous surface, which is mainly attributed to the changing stability of oil or water film covering the membrane surface. Additionally, this novel nanoscale hydrophilic-hydrophobic heterojunction system with dual superlyophobicity and excellent flexibility can not only separate both oil-in-water emulsion and water-in-oil emulsion simultaneously, but also achieve the lossless transfer in the droplet-based microreactor system under both water and oil environments. This may bring novel applications to the field of dual superlyophobicity. Moreover, this nanoscale hydrophilic-hydrophobic heterojunction system offers new and universal theoretical guidance for facile preparation of dual superlyophobic surfaces, owing to the richness in the functionality of low dimensional nanomaterials, it is foreseeable that more potential applications in various fields can be coupled with such an adaptable platform.

A Self-Detecting and Self-Cleaning Biomimetic Porous Metal-Based Hydrogel for Oil/Water Separation.

Porous materials with super-wetting surfaces (superhydrophilic/underwater superoleophobic) are ideal for oil/water separation. However, the inability to monitor the pollution degree and self-cleaning during the separation process limits their application in industrial production. In this study, a porous metal-based hydrogel is proposed, inspired by the porous structure of wood. Porous copper foam with nano-Cu(OH)2 is used as the skeleton, and its surface is coated with a polyvinyl alcohol, tannic acid, and multiwalled carbon nanotube cross-linked hydrogel coating. The hydrogel has superhydrophilicity and excellent oil/water separation efficiency (>99%) and can adapt to various environments. This approach can also realize hydrogel pollution degree self-detection according to the change in the electrical signal generated during the oil/water separation process, and the hydrogel can also be recovered by soaking to realize self-cleaning. This study will provide new insights into the application of oil/water separation materials in practical industrial manufacturing.

Recent advances in nature-inspired antifouling membranes for water purification

• Nature breaks new ground in the design of antifouling membranes. • The review summarizes the recent progress of nature-inspired antifouling membranes. • Fundamentals, strategies and applications of antifouling membranes are reviewed. • Challenges and perspectives for nature-inspired antifouling membranes are provided. Membrane separation technologies have been widely used for water purification. However, membrane fouling, which arises from unwanted deposition and adhesion of foulants, significantly hinders the applications of membrane technology. In recent years, inspirations that come through materials, processes and designs of nature open a new avenue for the development of antifouling membranes. The review aims to summarize the recent progress in nature-inspired antifouling membranes. The fundamentals of membrane fouling are first discussed based on the classical theories and recent advances in available literature. Subsequently, antifouling surfaces inspired from nature, involving superwetting surfaces, antimicrobial approaches and bio-synthesis strategies, are systematically summarized and antifouling membrane fabrications based on these strategies are critically reviewed. The challenges and perspectives are also discussed to facilitate the future research and development of nature-inspired antifouling membranes. This review provides comprehensive understanding and practical guidance on the construction of nature-inspired antifouling membranes for water purification.

Improved Stable Drag Reduction of Controllable Laser-Patterned Superwetting Surfaces Containing Bioinspired Micro/Nanostructured Arrays.

Superwetting surfaces are widely used in many engineering fields for reducing energy and resistance loss. A facile and efficient method using laser etching has been used to fabricate and control superwettable drag reduction surfaces. Inspired by the self-cleaning theory of lotus leaves, we propose controllable patterned bionic superhydrophobic surfaces (BSSs) simulating the uneven micro/nanostructures of lotus leaves. The superhydrophobicity and drag reduction ratios at low velocities are highly improved using a laser ablation method on metal substrates. However, unstable air layers trapped on superhydrophobic surfaces are usually cut away by a high-velocity flow, which greatly reduces the drag reduction performance. The fabricated bionic superhydrophobic/hydrophilic surfaces (BSHSs) with alternated hydrophilic strips can build a large surface energy barrier to bind the three-phase contact line. It maintains the stable drag reduction by capturing the air bubbles attached to the hydrophilic strips at a high velocity. Three-dimensional simulation analysis and equipment to measure the weak friction of a self-assembled solid–liquid interface are used to explain the drag reduction mechanism and measure the drag reduction ratios at different flow speeds. BSSs achieve an improved drag reduction effect (maximum 52.76%) at a low velocity (maximum 1.5568 m/s). BSHSs maintain an improved and steady drag reduction effect at high speed. The drag reduction ratios can be maintained at about 30% at high speed, with a maximum value of 4.448 m/s. This research has broad application prospects in energy saving, liquid directional transportation, and shipping due to their robust superhydrophobic properties and stable drag reduction effect.

Paper-based dual-mode liquid manipulation system: Oil/water separation and time-lapse droplet switch

Multi-mode liquid handling system integrated different types of liquid behaviors on super-wetting surfaces has attracted great interest from both academia and industries due to their promising applications in the field of surface science. Herein, a paper-based dual-mode droplet manipulation system that combines oil/water separation and time-delay droplet switch was designed by spray-coating α-cellulose 10-undecenoyl ester (CUE) particles on filter paper with further “reverse sizing” by polydimethylsiloxane (PDMS) based on capillary action and “like dissolve like” principle. Such novel binding technique leaded to a remarkably robust superhydrophobicity of the as-fabricated PDMS@CUE-coated paper (PDMS@CCP), including outstanding mechanical resistance and environmental durability. In particular, the front side of PDMS@CCP displayed excellent separation efficiency (higher than 99.89%) for light oil/water mixture, heavy oil/water mixture, and even surfactant-stabilized water-in-oil emulsion. Interestingly, based on the hydrophobicity of the back side of PDMS@CCP and the intrinsic hygroscopicity of paper itself, a time-delay droplet switch was simply achieved in between by the Laplace pressure derived from the curvature difference of the droplet on two paper surfaces with surface energy gradient. By adjusting the width of the filter paper and the volume of the droplet, the switch time could be rationally modulated between 0.8 and 202.1 s. The designed functional paper would enrich the application field of the liquid manipulation system.

Hybrid Superwetting Surfaces for Enhanced Condensation: Design of Hybrid Superwetting Surfaces with Self‐Driven Droplet Transport Feature for Enhanced Condensation (Adv. Mater. Interfaces 13/2021)

Hybrid superwetting surfaces with wedge-shaped superhydrophilic patterns that can transport droplets spontaneously are designed and fabricated to enhance drop-wise condensation, as demonstrated by Xiaolong Yang, Di Zhu, and co-workers in article number 2100284. The pattern design is optimized based on dynamic behavior of droplet transporting and condensing performance, which has great potential applications in developing new heat transfer devices, water desalination facilities, etc.

Design of Hybrid Superwetting Surfaces with Self‐Driven Droplet Transport Feature for Enhanced Condensation

AbstractPatterned hybrid superwetting surfaces that function in drop‐film‐wise condensation mode have great potential applications in heat transfer devices, water desalination, etc., due to the high performance of condensate transport. However, design and combination strategy for pattern optimization are still not clear. In this work, superhydrophobic surfaces with wedge‐shaped superhydrophilic patterns are created for enhanced condensation. Dependence of geometry, size, and combination of the patterns on droplet transporting and heat transfer coefficient is investigated. Results imply that superhydrophobic surface with array of single‐wedge‐shaped superhydrophilic patterns shows 30% improvement of heat transfer coefficient when compared with superhydrophobic surface, due to rapid condensate transferring from drop‐wise to film‐wise region, condensate converging and departing from the film‐wise region. Additionally, when compared with the surface with array of cluster‐wedge‐shaped superhydrophilic patterns, the surface with array of single‐wedge‐shaped superhydrophilic patterns have higher condensation efficiency because of the larger total circumference, which donate greater condensate transferring capacity. Moreover, single‐wedge‐shaped superhydrophilic patterns with large size show higher heat transfer coefficient than the patterns with small size due to lower saturated vapor pressure. This new fundamental insight can be used to develop new hybrid superwetting surfaces intended on engineering applications, such as water production and heat transfer.

Air superhydrophilic-superoleophobic SiO2-based coatings for recoverable oil/water separation mesh with high flux and mechanical stability

Due to the inherent differences in surface tension between water and oil, it is a challenge to fabricate air superhydrophilic-superoleophobic materials despite their promising potential in the field of oil/water separation. Herein, a facile approach is developed to fabricate air superhydrophilic-superoleophobic SiO2 coating by combination of controllable modifying SiO2 nanoparticle surface by both hydrophilic groups (i.e., –OH groups) and oleophobic groups (i.e., fluorinated groups) with constructing porous and hierarchical structures. Hydroxyl-modified SiO2 nanoparticles (NPs) are synthesized using a base-catalysed procedure in the presence of ammonia or NaOH. Chitosan quaternary ammonium salt (HACC) is introduced to bind SiO2 by forming a unique hydrogen bond between HACC and –OH, followed by adding pentadecafluorooctanoic acid (PFOA) to complex with HACC to form fluorinated groups. The SiO2 coatings are fabricated on various substrates (e.g., glass, foam and Cu mesh) by spraying procedure and characterized using SEM, FTIR, XPS, etc. The contact angles of oils (e.g., pump oil, castor oil, corn oil, hexadecane and bean oil) and water on the coatings are over 150° and close to 0°, respectively. By optimization, the representative SiO2-coated Cu mesh displayed high-efficiency of 99.2% in separating water from mixture of water/pump oil, and high penetration flux of 1.41 × 104 L·m−2 ·h−1. Besides, the coating maintains its superhydrophilic-superoleophobic properties even after 110 cycles of sandpaper abrasion or after being immersed in water for 3 h. After 20 cycles of oil/water separation, the coating retains separation efficiency up to 97.93%. This study provides a new and universal protocol to fabricate unique superwetting surfaces with effective oil/water separation performance, long-term durability and outstanding reusability.