A robust and stretchable superhydrophobic PDMS/PVDF@KNFs membrane for oil/water separation and flame retardancy

Facile Construction of Chestnut-Like Structural Fireproof PDMS/Mxene@BN for Advanced Thermal Management and Electromagnetic Shielding Applications

Composite polymer materials featured superior thermal conductivity, flame retardancy, and electromagnetic shielding performance are increasingly in demand due to the rapid development of highly miniaturized, portable, and flexible electronic devices. Herein, a facile and green ball milling shear method is utilized for generating MXene@Boron nitride (MXene@BN). The multi-functional fillers (MXene@BN) are constructed and incorporated into polydimethylsiloxane (PDMS) to prepare a multifunctional composite (PDMS/MXene@BN) for achieving improved electromagnetic interference (EMI) shielding performance and thermal conductivity as well as flame retardancy simultaneously. When the PDMS/MXene@BN composite has a MXene@BN loading of 2.4 wt.%, it exhibits a high thermal conductivity of 0.59 W m-1K-1, which is 210% higher than that of the pure PDMS matrix. This is attributed to its unique chestnut-like double-layer structure. With a smoke production rate (SPR) of 0.04 m2 s-1 and total smoke production (TSP) of 3.51 m2, PDMS/MXene@BN 2.4 composite exhibits superb smoke suppression properties. These SPR and TSP values are 63.20% and 63.50% lower than the corresponding values of pure PDMS. Moreover, the EMI SE of the PDMS/MXene@BN 2.4 can reach 26.3 dB at 8.5 GHz. The work reported herein provides valuable insight into developing composites with multiple functions, which show strong potential for application in advanced packaging materials.

CdO-Nanografted Superhydrophobic Hybrid Polymer Composite-Coated Cotton Fabrics for Self-Cleaning and Oil/Water Separation Applications

The current study presents a simple and cost-competitive method for the development of high-performance superhydrophobic and superoleophilic cotton fabrics coated with cadmium oxide/cerotic acid (CdO/CE)-polycaprolactone (PCL)- and cadmium oxide/stearic acid (CdO/ST)-polycaprolactone-grafted hybrid composites. X-ray powder diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy are used to characterize the CdO/CE-PCL and CdO/ST-PCL and polycaprolactone-modified cotton fabrics. Using an optical contact angle meter, the wetting behavior of corrosive liquids such as coffee, milk, tea, water dyed with methylene blue, strong acids (HCl), strong alkali (NaOH), and saturated salt solution (NaCl) on the CdO-CE/ST/PCL-modified cotton fabrics is assessed as well as the durability of CdO-CE/ST/PCL-modified cotton fabrics in corrosive liquids. Data obtained from the oil-water separation experiment indicate remarkable separation efficiency with oil purity values of ≥99.97 wt %, and high permeation flux values of up to 11,700 ± 300 L m-2 h-1 are observed for surfactant-stabilized water-in-oil emulsions via a gravity-driven technique. From the data obtained, it is concluded that the nano-CdO-grafted superhydrophobic hybrid polymer composite-coated cotton fabrics (CdO-ST/(CE)/PCL/CFs) can be utilized for self-cleaning and oil/water separation applications.

Mussel-Inspired Fabrication of an Environment-Friendly and Self-Adhesive Superhydrophobic Polydopamine Coating with Excellent Mechanical Durability, Anti-Icing and Self-Cleaning Performances

Superhydrophobic coatings play a crucial role in self-cleaning and anti-icing infrastructure areas under harsh service environments such as very low temperature, strong wind, and sand impact. In the present study, an environment-friendly and self-adhesive superhydrophobic polydopamine coating inspired by mussels had been successfully developed and its growth process was accurately regulated by formula and reaction ratio optimization. The preparation characteristic and reaction mechanism, surface wetting behavior, multi-angle mechanical stability, anti-icing, and self-cleaning tests were systematically investigated. The results showed that the superhydrophobic coating achieved an ideal static contact angle of 162.7° and a roll-off angle of 5.5° through the proposed self-assembly technique in an ethanol-water solvent. This was due to the coupling effect of constructing a hierarchical roughness structure on the coating surface and reducing its surface energy, which had been well documented by the surface morphology characteristic and chemical structure analysis. The as-prepared coating's self-mechanical performances (tensile strength/shear holding power) and surface wear resistance (sand impact/sandpaper abrasion) behaviors were tested, and results showed tight internal compactness and excellent mechanical robustness, respectively. Furthermore, the 180° tape-peeling on 100 cycles and pull-off adhesion tests indicated that the above coating had significant mechanical stability and an increased percentage (57.4%) of interface bonding strength (27.4 MPa) with steel substrate compared to pure epoxy/steel. This was attributed to the metal chelating capacity between polydopamine catechol moieties and steel. Finally, the superhydrophobic coating had obvious self-cleaning properties by using graphite powder as a contaminant. Additionally, the coating had a higher supercool pressure and displayed much-reduced icing temperature, a longer icing delay time, and an extremely low and stable ice adhesion strength (0.115 MPa) owing to the extreme water-repellence and mechanical durability.

Enhanced air filtration performances by coating aramid nanofibres on a melt-blown nonwoven

Nanofibre membranes with a small diameter and a large specific surface area are widely used in the filtration field due to their small pore size and high porosity. To date, aramid nanofibres (ANFs) have received extensive research interest because of their high stiffness and excellent temperature resistance. However, the preparation of ANFs usually takes a long time, which greatly hampers the practical application of these fibres. Herein, we report the preparation of ANFs by a modified deprotonation method at elevated temperature. Owing to the increase of temperature, the preparation cycle of ANFs was shortened to 8 hours. The resulting ANF dispersion was further coated on a polypropylene melt-blown nonwoven to form a composite nonwoven filter. With the submicron porous structure, the filtration efficiency, pressure drop and quality factor of the filter were 95.61%, 38.22 Pa and 0.082 Pa^-1, respectively. Compared to the pristine nonwoven, the filtration, mechanical, and heat insulation properties of the composite filter were also significantly improved. This work may offer a simple and efficient way for enhancing the air filtration performances of current filters.

Preparation strategy and evaluation method of durable superhydrophobic rubber composites

Superhydrophobic rubber composites have broad application prospects in national defense, industrial and agricultural production and daily life due to their special surface wettability. However, its poor durability at present seriously limits its practical application. Microstructure and low surface energy substances are the decisive factors to realize superhydrophobic surface. Therefore, three strategies to improve the durability of superhydrophobic surface were put forward, including improving the mechanical strength of microstructure, enhancing the adhesion between coating and substrate, and constructing self-repairing surface. On this basis, the preparation techniques of durable superhydrophobic rubber composites were summarized, and then the evaluation methods of durability of superhydrophobic rubber composites were introduced in detail from mechanical durability and chemical durability.

Solvent-free processing of eco-friendly magnetic and superhydrophobic absorbent from all-plant-based materials for efficient oil and organic solvent sorption

The unique features of bioresources such as cellulose and bio-wax include renewability, biodegradability, low cost, and abundance on Earth. Therefore, their efficient use is essential for a sustainable economy. Herein, we report a facile method for the surface modification of pretreated cotton with a bio-wax emulsion in water and Fe₃O₄ nanoparticles to fabricate a green, durable, magnetic, and superhydrophobic/superoleophilic absorbent for the sorption of oil and organic solvents. Magnetic superhydrophobic cotton (MSC) was successfully prepared via a simple two-step dip-coating method without using any toxic organic reagents. The as-prepared MSC was used to selectively absorb various types of oils and organic solvents up to approximately 20-50 times its own weight. Furthermore, it exhibited a stable magnetic responsivity and high reusability in oil/water separation cycles. In addition, the removal and collection of the absorbed oil/organic solvents were easily achieved with distillation and a vacuum air pump. Moreover, the as-prepared MSC was used in a heavy oil/water gravity-separation filter system and in the continuous collection of a light oil from water surfaces using a pump. The proposed concept may provide a green and sustainable strategy for fabricating superhydrophobic/superoleophilic materials for efficient sorption of oils and organic solvents.

Review on the recent development of durable superhydrophobic materials for practical applications

Biomimetic superhydrophobic surfaces show great potential in oil-water separation, anti-icing and self-cleaning. However, due to the instability caused by its fragile structure and non-durable superhydrophobicity, it is difficult to apply them in the actual field. Here, by introducing surface wettability and analysing the mechanism of superhydrophobic failure, it is concluded that the reason for the failure of the superhydrophobic surface comes from the transition of the surface energy and the hysteresis of the contact angle (CA). On the basis of this analysis, it is concluded that the principle of designing a durable superhydrophobic surface is to satisfy one of the following three points: improving the binding force between molecules, introducing durable materials and improving chemical durability. On this basis, a variety of preparation methods are proposed, such as assembly method and spray/dip coating method, and the design and preparation of a self-healing surface inspired by nature will also be included in the introduction. Last but not least, the preparation and application of a durable super-hydrophobic surface in oil-water separation, anti-icing and self-cleaning are also introduced in detail. This review reveals the conclusions and prospects of durable superhydrophobic surfaces, and aims to inspire more researchers to invest in this research.

One-Step Fabrication of a Micro/Nanosphere-Coordinated Dual Stimulus-Responsive Nanofibrous Membrane for Intelligent Antifouling and Ultrahigh Permeability of Viscous Water-in-Oil Emulsions

Membrane fouling is a major challenge for long-term oil/water separation. The incomplete degradation of organic pollutants or membrane damage exists in the common methods of membrane regeneration. Herein, a dual-responsive nanofibrous membrane with high water-in-oil emulsion separation efficiency and smart cleaning properties is reported, which shows complete restoration of its original separation performance. The pH-responsive and upper critical solution temperature (UCST)-type thermoresponsive nanofibrous membrane with a micro/nanosphere structure was developed via a one-step-blending electrospinning strategy. The membrane displays high hydrophobicity/oleophilicity at pH 7 and 25 °C and hydrophilicity/oleophobicity at pH 3 and 55 °C. As a result, it exhibits an ultrahigh permeability of 60528.76 L m^-2 h^-1 bar^-1 and a separation efficiency of 99.5% for water-in-D5 emulsions at room temperature (25 °C). Moreover, the contaminated membranes could be easily reclaimed by being rinsed with warm acidic water (pH 3 and 55 °C). The membrane maintained high separation performance after being used for multiple cycles, indicating its scalable application for purifying emulsified oil. This study provides a facial method of constructing membranes with multiscale hierarchical structures and a new idea for the design of recyclable oil/water separation membranes.

Stable and Durable Conductive Superhydrophobic Coatings Prepared by Double-Layer Spray Coating Method

Herein, a low cost, durable, and stable conductive superhydrophobic composite coating (CSC coating) was fabricated on a Q345 steel surface by simple double-layer spray coating. The water contact angle (WCA) of the CSC coating was 160° and the sliding angle (SA) was 3°. In addition to its excellent conductivity (3.10 × 103 Ω), the fabricated composite coating had good durability and wear resistance. After 10 sand-washing cycles, the CSC coating surface still exhibited stable superhydrophobicity (149° WCA, 9.5° SA). At 200 g pressure, the surface of the optimized CSC coating still maintained fine superhydrophobicity (150° WCA, 9.2° SA) and conductivity (1.86 × 104 Ω) after 10 abrasion cycles. In addition, it also exhibited fine adhesion (0.307 MPa) between the composite coating and the substrate. This functional superhydrophobic surface can be applied in specialty fields with harsh conditions such as coal mining and petrochemical activities. This new coating may also expand the application fields of superhydrophobic surfaces and have broad practical application prospects.

Robust superhydrophobicity: mechanisms and strategies

Superhydrophobic surfaces hold great prospects for extremely diverse applications owing to their water repellence property. The essential feature of superhydrophobicity is micro-/nano-scopic roughness to reserve a large portion of air under a liquid drop. However, the vulnerability of the delicate surface textures significantly impedes the practical applications of superhydrophobic surfaces. Robust superhydrophobicity is a must to meet the rigorous industrial requirements and standards for commercial products. In recent years, major advancements have been made in elucidating the mechanisms of wetting transitions, design strategies and fabrication techniques of superhydrophobicity. This review will first introduce the mechanisms of wetting transitions, including the thermodynamic stability of the Cassie state and its breakdown conditions. Then we highlight the development, current status and future prospects of robust superhydrophobicity, including characterization, design strategies and fabrication techniques. In particular, design strategies, which are classified into passive resistance and active regeneration for the first time, are proposed and discussed extensively.

Gravity-Driven Separation of Oil/Water Mixture by Porous Ceramic Membranes with Desired Surface Wettability

Porous Al₂O₃ membranes were prepared through a phase-inversion tape casting/sintering method. The alumina membranes were embedded with finger-like pores perpendicular to the membrane surface. Bare alumina membranes are naturally hydrophilic and underwater oleophobic, while fluoroalkylsilane (FAS)-grafted membranes are hydrophobic and oleophilic. The coupling of FAS molecules on alumina surfaces was confirmed by Thermogravimetric Analysis and X-ray Photoelectron Spectroscopy measurements. The hydrophobic membranes exhibited desired thermal stability and were super durable when exposed to air. Both membranes can be used for gravity-driven oil/water separation, which is highly cost-effective. The as-calculated separation efficiency (R) was above 99% for the FAS-grafted alumina membrane. Due to the excellent oil/water separation performance and good chemical stability, the porous ceramic membranes display potential for practical applications.

A superhydrophobic surface with aging resistance, excellent mechanical restorablity and droplet bounce properties

The use of a silicone rubber composite insulator has become an important aspect to ensure the safe operation of an electrical power grid. This study introduces a preparation method of a superhydrophobic silicone rubber surface using a simple preparation process at low cost and with excellent performance, which can be used in the mass production of silicone rubber composite insulators. In this study, the combination of a compression molding process and a template method was used to prepare the product. A microstructure composed of numerous boat-shaped grooves was constructed on the surface of silicone rubber. The modification of a low surface energy material is not required. The static contact angle with water after the high-temperature treatment exceeds 150°, and the rolling angle is under 10°. Excellent performance has been observed in terms of self-cleaning effect, aging resistance, and mechanical and droplet bounce properties. It has been shown that the loss of superhydrophobic properties, due to the prolonged immersion in water, can be restored by a high temperature heating process.

Superhydrophobic Nickel-Electroplated Carbon Fibers for Versatile Oil/Water Separation with Excellent Reusability and High Environmental Stability

Superhydrophobic filtrating materials have been widely developed for rapid removal or collection of oils from oil/water mixture due to the increasing water pollution caused by oil spills and oil-contaminated wastewater. However, poor reusability, superhydrophobic failure in harsh environments, and that only heavy oil or light oil was separated from water seriously restricted their practical application. Herein, superhydrophobic carbon fibers were first fabricated using a novel nickel electroplating for versatile oil/water separation with excellent reusability and high environmental stability. The interconnected nanometer-scale nickel grains formed on the micrometer-scale fibers and fluoroalkylsilane molecules enabled the fibers to be superhydrophobic with the water contact angle (CA) of ∼159.1° and superoleophilic with the oil CA of ∼0°. The nickel coating contributed to the improvement of the bonding strength, tensile strength, and oxidation resistance of the fibers. The as-prepared fibers could be applied for the separation of heavy or light oil/water mixtures with separation efficiencies above 99.1%, during which the oil content in the separated water all remained below 78 ppm. The fibers also realized the highly efficient separation of dichloromethane and various harsh environmental solutions such as hot water, acid, alkali, and salt. The superhydrophobicity of the fluorinated nickel-coated carbon fibers still remained even after 100 cycles of separation and 24 months of storage in air, demonstrating outstanding durability of the fibers. These novel superhydrophobic carbon fibers had promising potentials for versatile oil/water separation in practical applications.

Robust super-hydrophobic/super-oleophilic sandwich-like UIO-66-F4@rGO composites for efficient and multitasking oil/water separation applications

Super-wetting MOFs@graphene hybrid has shown promising application for oil/water separation, due to high porosity, low density, and controllable wettability, however, achieving excellent stability and recyclability are found to be still challenging. In this study, sandwich-like UIO-66-F₄@rGO hybrid was synthesized by immobilization of UIO-66-F₄ nanoparticles on rGO matrix, which featured the unique micro/nano hierarchy with hydrophobic characteristics. In order to realize the oil/water separation, as-prepared sandwich-like UIO-66-F₄@rGO hybrid was applied as a potential candidate for constructing robust super-hydrophobic/super-oleophilic interfaces by using filter paper (FP) and melamine sponge (MS) as substrates. Typically, the surface modification of substrates can be easily achieved by simple dip-coating method, and interfacial adhesion between substrates and UIO-66-F₄@rGO was enhanced by cross-linking of hydroxyl-fluoropolysiloxane (FPSO). Consequently, the super-hydrophobic/oleophilic UIO-66-F₄@rGO/FP exhibited high contact angle of 169.3 ± 0.6° and was capable of separating various water-in-oil emulsions effectively. The flux and separation efficiency were 990.45 ± 36.28 Lm^-2 h^-1 and 99.73 ± 0.19 % driven by gravity, respectively. The super-hydrophobic/super-oleophilic UIO-66-F₄@rGO/MS possessed selective oil absorption with absorption capacity of 26∼61 g/g depending on the viscosity of oils and continuous cleaning of oil spill. Furthermore, the UIO-66-F₄@rGO composite could tolerate high/low temperature, corrosive solutions, and physical damage, displaying robust and stable super-hydrophobic/super-oleophilic interfaces for treating oily wastewater in harsh environments.

A Robust and Versatile Continuous Super-Repellent Polymeric Film for Easy Repair and Underwater Display

Functionalized super-repellent polymeric materials play important roles in academic and industrial fields. In this work, a versatile continuous super-repellent polymeric film (CSPF) integrating reversible wettability with design manipulation was synthesized. On the basis of the optimal combination of a polyurethane acrylate (PUA)/precipitated silica particle (PSP)/ethanol suspension, covalently cross-linking networks and hierarchical topography were constructed in a polymer skeleton, endowing the CSPF with solid mechanical strength (B hardness). Taking advantage of the continuous superhydrophobicity established by the silica particle across the film bulk, the CSPF was found to be repetitively exposed via the shedding of the surface layer to achieve reversible wettability and repair its nonwetting performance (>50 cycles). Accordingly, the continuous superhydrophobicity and regenerative feature enabled the CSPF to realize design manipulation successively and underwater display rapidly, which may broaden the application fields of super-repellent materials in marine transportation and undersea exploration. Furthermore, the CSPF also displayed enticing damage-resistance (>200 cycles), environmental stability (>5 days), and self-cleaning behavior. Our findings convincingly propose a feasible approach to fabricate versatile super-repellent polymeric materials as candidates for advanced and smart materials.

The fabrication of mechanically durable and stretchable superhydrophobic PDMS/SiO2 composite film

Stretchable superhydrophobic film was fabricated by casting silicone rubber polydimethylsiloxane (PDMS) on a SiO₂ nanoparticle-decorated template and subsequent stripping. PDMS endowed the resulting surface with excellent flexibility and stretchability. The use of nanoparticles contributed to the sustained roughening of the surface, even under large strain, offering mechanically durable superhydrophobicity. The resulting composite film could maintain its superhydrophobicity (water contact angle ≈ 161° and sliding angle close to 0°) under a large stretching strain of up to 100% and could withstand 500 stretching–releasing cycles without losing its superhydrophobic properties. Furthermore, the obtained film was resistant to long term exposure to different pH solutions and ultraviolet light irradiation, as well as to manual destruction, sandpaper abrasion, and weight pressing.

Stretchable superhydrophobic film was fabricated by casting silicone rubber polydimethylsiloxane (PDMS) on a SiO₂ nanoparticle-decorated template and subsequent stripping.

Modification of Supramolecular Membranes with 3D Hydrophilic Slide-Rings for the Improvement of Antifouling Properties and Effective Separation

A three-dimensional (3D) strategy for the fabrication of ethylene vinyl alcohol (EVAL) membranes with a dynamic surface was developed based on sliding supramolecular polymer brushes (SSPBs). The SSPBs with a 3D hydrophilic structure were introduced into the alkyne-EVAL membrane matrix via an azide-alkyne click coupling reaction. The self-mobile hydrophilic slide-rings in the SSPB provided a proactive exclusion system. This resulted in reduced direct contact of the membrane surface with multiple pollutants such as bovine serum albumin (BSA) and oil droplets. The EVAL-SSPB membrane demonstrated increased surface hydrophilicity, underwater oleophobicity, and antifouling properties. More importantly, the abundant hydrophilic rings in the membrane matrix result in supramolecular assembly and efficient hydrophilic sliding channels. This resulted in a dramatic increase in the water flux [2000 L/(m² h)] while retaining a 96% rejection of BSA and oil/water emulsions. The results of the study indicate that three effects of the cyclodextrins rings, i.e., the hydrophilic effect, the exclusion effect, and the sliding effect, enabled the improved membrane performance. The demonstrated 3D fabrication strategy is versatile, facile, and scalable, which allows for its application to various other membranes. The fabricated materials possess excellent permeability and separation efficiencies, which make them attractive candidates for use as separation membranes with novel functions.

Designing Carbon Nanotube-Based Oil Absorbing Membranes from Gamma Irradiated and Electrospun Polystyrene Nanocomposites

Carbon-based materials are outstanding candidates for oil spill clean-ups due to their superhydrophobicity, high surface area, chemical inertness, low density, recyclability, and selectivity. The current work deals with the fabrication of membrane oil absorbents based on carbon nanotube (CNT) reinforced polystyrene (PS) nanocomposites by electrospinning technique. The spun membranes are also irradiated with the gamma radiation to induce enough crosslinks and thus good polymer-filler interactions. The structural, morphological, and surface properties in addition to the oil/water separation efficiency were investigated by varying the concentration of CNT and the dose of γ-irradiation. Fabricated nanofiber membranes show superior hydrophobicity and selective oil absorption at 0.5 wt.% of CNT concentration. The best mechanical properties are also obtained at this particular concentration and at 15 KGy optimum γ-irradiation dosage. The gamma irradiated PS/0.5 wt.% CNT membrane also exhibits good antibacterial effects against the bacteria, Escherichia coli, in the form of bacterial inhibition rings around the membranes. The present study thus shows the environmental applicability of the fabricated PS/CNT membranes in treating oil-contaminated water.

An oil/water separation nanofibrous membrane with a 3-D structure from the blending of PES and SPEEK

A new nanofibrous membrane (NFM) was prepared by blending polyethersulfone (PES) and sulfonated poly(ether ether ketone) (SPEEK) via electrospinning. The membrane exhibits good thermal stability and high mechanical strength. The hydrophilicity of the membrane could be controlled by adjusting the mass ratio of PES to SPEEK. PES acts as the backbone fiber and provides high mechanical strength, while SPEEK provides hydrophilic functional groups due to the strong hydrophilicity of the sulfonic group. The test results show that the composite NFM integrates the advantages of the two polymers. Simple adjustment of the weight ratios of the two polymers can enable an adjustable flux so that the membrane can be used for different kinds of oil/water separation. The results show that NFMs can not only separate immiscible oil/water systems but also separate oil-in-water emulsions. The immiscible oil/water separation process was driven only by gravity and had a high flux of 1119.63 Lm−2 h−1. This separation process conserves energy, which is beneficial for environmental protection. The separation flux of the oil-in-water emulsion was 758.71 Lm−2 h−1 bar−1 based on measurements under different pressures, and the separation purity total organic carbon was below 50 ppm. This work indicates that a membrane comprised of PES and SPEEK has excellent performance and can be used in different fields.

Preparation and performance testing of superhydrophobic flame retardant cotton fabric

A superhydrophobic flame retardant coating was fabricated using a simple method of depositing a DAP coating and a H-ZrO₂@PDMS coating on the surface of a cotton fabric. Thermal stability tests and vertical burning tests demonstrate the excellent flame retardancy of the coating.

Effect of liquid droplet surface tension on impact dynamics over hierarchical nanostructure surfaces

Analyzing impact dynamics is important for practical applications of superhydrophobic surfaces, because these nonwetting surfaces frequently encounter impacting liquid droplets in real environments. Thus, various studies have been conducted to investigate impact dynamics by examining the correlation between the behaviors of impacting liquid droplets and several determining parameters, such as impacting velocity, surface structure and surface energy. The impacting behaviors of pure water droplets were the main focus in most previous studies; the effect of surface tension, another critical parameter, on impact dynamics has rarely been investigated. In the current work, we have newly studied the effects of liquid surface tension on impact dynamics using an ethanol-water solution as a model liquid system. We systematically varied the liquid's surface tension between 72 and 32 mN m-1 by changing the ethanol concentration from 0 to 20 wt%. This range of composition drastically changed the surface tension while it did not significantly affect other physical properties, such as density and viscosity. For an impact dynamics study, two surfaces, namely ZnO nanowires (NWs) and ZnO/Si hierarchical (HIE) structures, were prepared. As the surface tension decreased, the static water contact angle (CA) decreased on both surfaces. Under dynamic conditions, our analysis using a high-speed camera and a quartz crystal microbalance (QCM) showed that lowering the surface tension causes the transition from the anti-wetting to wetting state. The transition We numbers were obtained on both surfaces for various surface tensions of liquids. Under the same dropping conditions of liquids, the ZnO/Si HIE surface shows higher transition We numbers than the ZnO NW surface, which is due to the higher fraction of air pockets in the hierarchical structure, originating from dual dimensional structures. To understand the mechanism of dynamic transition, we developed a model for ZnO/Si HIE structures based on three determining pressures: anti-wetting, wetting, and effective water hammer pressures. The modeling results explain the experimental observations. The results of our model system are highly useful for understanding the impact dynamic behaviors of various liquids on non-wetting surfaces.