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A fluorine‐free and multifunctional superhydrophobic coating (r‐MSC) was prepared by the one‐step spraying method. The coating had superhydrophobic and low‐adhesion properties with the water contact angle of 161.5° ± 1° and the sliding angle of 3.2° ± 0.5°. It could be prepared by spraying while maintaining superhydrophobic surface characteristics on any substrates. The coating owed outstanding mechanical durability and chemical stability. Moreover, the coating also possessed the ability of self‐cleaning, anti‐fouling, anti‐icing, and flame retardant ability. Importantly, the presence of multifunctional coating endowed the substrate with both water‐resistant and fireproof properties. Besides, it also showed excellent oil‐water separation ability, which presented the oil‐water separation efficiency of over 90% for different types of oils after 10 separation cycles. Furthermore, the coating could improve corrosion inhibition performance and the corrosion current density was reduced by two orders of magnitude from the polarization curve. The r‐MSC had the advantages of simple preparation, fluorine‐free, environmentally friendly and appropriate for large‐area fabrication, which could be applied to various fields. [ABSTRACT FROM AUTHOR]

In nature, fluid manipulation plays a crucial role in the life of organisms, which has attracted great attentions of research and industry. Here, a functional bionic cilia surface is designed via the simple magnetic field assistance and laser etching technique. Multidirectional droplet transportation occurs on superhydrophobic cilia surface, which has good mechanical, physical, and chemical stability. The as‐prepared surface covered with cilia in the superhydrophobic (WCA of 156 ± 2°) and hydrophobic (WCA of 119 ± 3°) area possess different adhesion state, which can be used for multiple chemical reactions as a microreaction platform. Furthermore, bionic cilia surface can be used as a transport tool in the analysis and detection with average transfer speed of 2.3 cm s−1, which provides new opportunities in the development of small analysis equipment. Importantly, magnetically induced bionic cilia surfaces have broad potential applications in developing smart surfaces, droplet control, lab‐on‐a‐chip, etc. [ABSTRACT FROM AUTHOR]

Droplet manipulation holds importance across various domains, including microfluidics, bioassays, water harvesting, and transportation. Drawing inspiration from nature, specifically the superhydrophobic surface of lotus leaves and the patterned surface of desert beetles, this research explores the creation of bionic magnetic superhydrophobic and patterned surfaces with programmable manipulation of droplets, including transport, mixing, and single-droplet multiplex dispersion. The surfaces are prepared using a straightforward laser selective etching technique, during which droplets easily bounce off the laser-etched surface, exhibiting low adhesion, whereas they adhere firmly to non-etched areas. The introduction of a magnetic field induces surface deformation, facilitating droplet transport under unbalanced forces on the bionic surface. Further, the feasibility of using patterned surfaces as platforms for chemical microreactions is confirmed through chemical reactions. This study offers insights into the development of functional surfaces and highlights their potential applications in rapid, high-throughput detection. [Display omitted] • The method of preparing surfaces is simply. • Droplets can be programmable transported easily on superhydrophobic surface. • Bionic patterned surface has ability to disperse single droplet at multiple sites. • The bionic surfaces show advantages in autonomous detection. [ABSTRACT FROM AUTHOR]

Superhydrophobic multifunctional coatings have wide application prospects in construction, shipping, transportation equipment and aerospace etc. In this paper, a fluorine-free photocatalytic superhydrophobic coating with long-lasting anticorrosion performance and excellent antibacterial ability has been developed on various substrates by a simple spraying method. The coating is mainly composed of epoxy resin (EP), polydimethylsiloxane (PDMS) and hydrophobically modified micron ZnO (m-ZnO) and nano ZnO (n-ZnO). The coating maintains excellent wettability to various common liquids, and the water contact angle (WCA) and sliding angle (SA) of coating are 162.8° and 3°, respectively. The synergistic effect of the air layers and the coating denseness endows coating with excellent corrosion inhibition efficiency (η p > 99.9 %) in 3.5 wt% NaCl solution and neutral salt spray tests for 30 days. The photocatalytic activity and superhydrophobicity endow coating with bactericidal activity and antibacterial adhesion properties, thus providing the coating with excellent antibacterial ability in dynamic or static liquid environment. Furthermore, the coating can withstand chemical erosion, ultraviolet radiation and mechanical durability tests such as knife scraping, tape peeling and sandpaper wear cycles. This large-scale fabrication, environmentally benign, low cost and high performance coating has potential practical applications in a wider range of fields. [Display omitted] • Fluorine-free superhydrophobic multifunctional coatings are prepared by a spraying method. • Photocatalytic activity and superhydrophobicity endow coating with bactericidal activity and antibacterial adhesion abilities. • The coating presents long-lasting anticorrosion performance in wet atmospheric or liquid environment. • The coating presents excellent wettability, stability and durability. [ABSTRACT FROM AUTHOR]

• Biomimetic stainless-steel surfaces were prepared by laser etching and modification. • MD simulations suggested the PDA@ODA compounds how to adsorb on the substrate. • The results of MD simulations were consistent with experimental data. • The surfaces presented superhydrophobicity, antibacterial property and stability. Wettability is an effective strategy to reduce the adhesion force between bacteria and a solid surface, also is favor to effectively overcome the limitation of the substrate materials and expand their practical applications. Herein, inspired by the special micro/nano structures of the creatures and the bioadhesion of marine mussels, a green and simple two-step method, the laser interference patterning and in-situ polymerization, was used to fabricate the superhydrophobic surface with antibacterial property on the stainless-steel (SS) substrate. As well, this patterned surface also has successfully realized the wettability transition from superhydrophilic to superhydrophobic. Meanwhile, the results of MD simulations directly suggested the PDA@ODA compounds how to adsorb on the SS substrate and interact with water molecules, which was consistent with the experimental. In addition, according to the agar plate assays and fluorescent microscope tests, the obtained specimens presented a certain antimicrobial activity. Moreover, the samples had good robustness in the heat resistance, physical performance and durability, which will expand the application fields and working life. [ABSTRACT FROM AUTHOR]

Superamphiphobic (both superhydrophobic and superoleophobic) surfaces have attracted great interests in the fundamental research and practical application. This research successfully fabricated the superamphiphobic surfaces by combining the nickel plating process and modification with perfluorocaprylic acid. The cooperation of hierarchical micro-nano structures and perfluorocaprylic acid with low surface energy plays an important role in the formation of superamphiphobic surfaces. The contact angles of water/oil have reached up to 160.2 ± 1°/152.4 ± 1°, respectively. Contrast with bare substrate, the electrochemical measurements of superamphiphobic surfaces, not only the EIS measurement, but also potentiodynamic polarization curves, all revealed that, the surface corrosion inhibition was improved significantly. Moreover, superamphiphobic surfaces exhibited superior stability in the solutions with a large pH range, also could maintain excellent performance after storing for a long time in the air. This method is easy, feasible and effective, and could be used to fabricate large-area mutli-functional surface. Such a technique will develop a new approach to fabricate superamphiphobic surfaces on different engineering materials. [ABSTRACT FROM AUTHOR]

Inspired by the antifouling property of superhydrophobic surfaces of creatures, developing hybrid materials by loading antibacterial agents of silver nanoparticles on the superhydrophobic stainless-steel meshes, has been successfully achieved by the combination of double-potential deposition and in-situ polymerization grafting method. This study systematically investigated the effects of influencing factors on the Ag nanoparticles topography in the electrodeposition process, including nucleation potential, nucleation time, growth potential and growth time etc. According to the results of the inhibition zone test, from the comparative analysis of the antibacterial effect of the prepared specimens under different deposition parameters, it can be seen that the growth time during the double-potential deposition process had a relatively significant effect. Meanwhile, the presence of Ag nanoparticles is favor to improve the polymerization grafting of PDA@ODA compounds, which exhibited a superhydrophobic state with WCA of 160.6° and SA of 3°. No matter in static or dynamic culture process, the superhydrophobic surfaces were beneficial for reducing bacterial adhesion, ascribed to the superhydrophobic and antibacterial performance associated with the synergistic effect of organic PDA@ODA compounds and inorganic Ag nanoparticles. Moreover, the superhydrophobic stainless-steel mesh have good long-term stability and mechanical stability, which is favor to expand the application scope and working life. Unlabelled Image • Stainless-steel meshes were prepared by double-potential deposition and modification. • The superhydrophobic surfaces were beneficial for reducing bacterial adhesion. • The surface presented superhydrophobicity, antibacterial property and stability. [ABSTRACT FROM AUTHOR]

• A non-fluorinated electrothermal/superhydrophobic coating was obtained. • The coating has good mechanical and chemical stability, and in-situ self-healing ability. • The coating has excellent static and dynamic anti-icing ability. • The coating exhibits a long-term anti-corrosion effect for Mg alloy. The superhydrophobic surface has become a smart strategy for boosting the application of Mg alloy due to its anti-icing and anti-corrosion abilities. However, its application has been limited due to some drawbacks, such as harmful fluorinated materials, poor mechanochemical robustness, and unsatisfactory anti-icing performance in extreme environments. Herein, a non-fluorinated electrothermal/superhydrophobic coating, including bottom insulation and top superhydrophobic films, is prepared on Mg alloy by spray method. The superhydrophobic coating exhibits good mechanical robustness, chemical stability, and in-situ electrothermal-healing ability against plasma and chemical etchings. The electrothermal characteristic and superhydrophobicity endow the coating with excellent static and dynamic anti-icing, de-frosting, and de-icing performances. Moreover, the superhydrophobic coating exhibits a long-term anti-corrosion effect due to a durable air layer and organic coating, and can recover the coating's corrosion resistance by repairing superhydrophobicity. We expect that this research provides a wise strategy for designing superhydrophobic coating with good mechanical robustness, good chemical stability, electrothermal, in-situ self-healing, outstanding anti-icing, and long-term corrosion protection abilities to meet functional needs of Mg alloy as well as other metal materials. [ABSTRACT FROM AUTHOR]

• A surface switchable between superhydrophobic and slippery states was obtained. • The surface state is switched by alcohol washing and lubricant-infusion. • The surface has reliable anti-corrosion ability and durable air or lubricant layer. • Both surface states can delay corrosion at an artificial defect area. Enlightened by anti-wetting living creature surfaces in nature, the superhydrophobic surface (SHS) and slippery liquid-infused porous surface (SLIPS) have been constructed on metal materials for solving engineering problems. In this research, we design a switchable surface between the SHS and SLIPS on Mg alloy to improve corrosion resistance and provide different water-repellent properties. The SHS and SLIPS are fabricated based on a laser-ablated polydimethylsiloxane@Al 2 O 3 @Fe 2 O 3 coating (PAFC). After laser processing, the irradiated PAFC consists of micro/nanostructured texture resulting in excellent superhydrophobicity. The SLIPS is fabricated by filling the lubricant into the laser-structured texture of the SHS. Then, the surface can be easily switched between the SHS and SLIPS by alcohol washing and lubricant-infusion. The non-irradiated PAFC acts as a superior and durable corrosion barrier. Notably, the switchable surface exhibits an excellent anti-corrosion ability (with large impedance modulus at 10−2 Hz about 1011 Ω cm2) in both surface states, which does not have any degradation after being immersed in 3.5 wt% NaCl aqueous solution for 60 days. The SHS and SLIPS have durable air and lubricant layers, respectively, repelling the corrosive species during the immersion test. Simultaneously, the SHS and SLIPS can delay corrosion at an artificial defect area. The SLIPS performs better in the above abilities than the SHS owing to the lubricant layer's stability and self-healing property. The SHS with droplet rolling mode has better droplet transportability, water shielding ability, and self-cleaning ability than those of the SLIPS with droplet sliding mode in dealing with dynamic droplets. Meaningfully, the surface with switchable wettability exhibits long-term corrosion protection and promises a wide range of application prospects of metals such as anti-icing, drag reduction, anti-fouling, etc. [ABSTRACT FROM AUTHOR]

Superhydrophilic and superhydrophobic surfaces were prepared on a rolled Mg-9Al-1Zn magnesium alloy (AZ91) sheet via the combination of simple laser ablation and annealing treatment. After annealing at 160 °C for 60 min, laser ablated superhydrophilic surface transformed into superhydrophobic surface with a water contact angle (WCA) as high as 158.8 ± 2°. Superwetting surfaces, including superhydrophilic and superhydrophobic surfaces, exhibit higher corrosion resistance based on the results of potentiodynamic polarization curves and electrochemical impedance spectroscopy. The corrosion inhibition mechanism of the superwetting surfaces are that, Al element in high volume fraction of fine-spherical Mg 17 Al 12 phases changed to solid-solution aluminum within the melted layer for superhydrophilic surface and the air layer stored by micro/nanostructure could hold back erosive solution for the superhydrophobic surface. It's believed that the facile and highly-efficient method will make magnesium alloys a better engineering application prospects. Unlabelled Image • Superwetting surfaces were prepared via simple laser ablation and annealing. • Absorption of organic matters contributes to wettability transformation. • The superwetting surfaces both improve the corrosion resistance of Mg alloy. • Corrosion inhibition correlates with re-dissolved behavior of Mg17Al12 phases and air layer. [ABSTRACT FROM AUTHOR]

• Tunable water adhesive superhydrophobic surfaces were obtained by etching. • Tunable water adhesion mechanism was discussed. • Dense microstructure contributes to durable anti-corrosion ability. • The superhydrophobic samples were applied to low-loss transport of microdroplet. Through a simple chemical etching and surface modification, superhydrophobic surfaces with tunable water adhesion were prepared on rolled Mg-3Al-1Zn (AZ31) and Mg-9Al-1Zn (AZ91) alloy sheets. The different water adhesion is described by three different wetting model, i.e. Wenzel, Cassie impregnating, and Cassie model. An in-depth investigation on anti-corrosion performances of low adhesive superhydrophobic AZ31 and AZ91 surfaces reveals that dense microstructure can effectively improve the stability of Cassie state, thus facilitating durable anti-corrosion ability. Simultaneously, the superhydrophobic surfaces with tunable water adhesion are demonstrated to be feasible in the application of low-loss transport of microdroplet. In addition, the as-fabricated superhydrophobic surfaces show high-temperature stability and chemical stability in a large range of temperature and pH, respectively. It is expected that this research can shed light on designing new anti-corrosion and tunable adhesive superhydrophobic surfaces, and as-fabricated superhydrophobic Mg alloys are promising in medical instruments, transport systems, micro-fluidic devices, and so on. [ABSTRACT FROM AUTHOR]