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Chemical or electrochemical corrosion of the concrete-based facilities causes potential safety hazards. Endowing the concrete with a commercial superhydrophobic coating with designed surface topography and chemical composition is an effective way to prevent the corrosion of the internal rebars. Although several methods have been adopted to combat the corrosion problem, developing an equipment-free, low-cost and scalable strategy for fabricating a robust superhydrophobic coating on the concrete surface is still a challenge. In this work, a robust superhydrophobic epoxy fixed corundum-silica-polydimethylsiloxane (ECSP) composite is fabricated as the concrete modification coating through an "armour" protection methodology via a facile and low-cost dip-coating process. The as-prepared ECSP composite consists of corundum microparticles (MPs) confined in the epoxy (EP) adhesive layer and silica nanoparticles (SiO 2 NPs) modified with a low-surface-energy coating. The corundum MPs with high rigidness and hardness function as a robust, protective "armour" structure, while the polydimethylsiloxane-modified SiO 2 NPs reside within the "armour" structure to provide superhydrophobicity. Benefitting from the armoured structure, the ECSP composite coated concrete exhibits an excellent robustness under various harsh conditions including mechanical abrasion, knife scratching, tape-peeling treatment, water jetting, UV irradiation, temperature treatment and chemical corrosion. Importantly, the ECSP composite coating successfully prevents the concrete (with a rebar in it) from the chemical and electrochemical corrosion. The corrosion current density (4.8 × 10−6 A·cm−2) of the ECSP coated concrete is two orders of magnitude lower than that of the unprotected concrete (1.17 × 10−4 A·cm−2), exhibiting its excellent corrosion resistance. Besides, the superhydrophobic ECSP composite coating can retard the formation of ice on the concrete surface at the temperature of −20 °C, exhibiting good anti-icing performance. This work opens a new avenue for the fabrication and application of the multifunctional superhydrophobic coating for concrete protection. • A robust superhydrophobic ECSP composite is fabricated as the concrete modification coating. • The ECSP composite coating exhibits an excellent robustness under various harsh conditions. • The ECSP coated concrete successfully prevents the chemical and electrochemical corrosion in a simulated corrosion environment. • The ECSP coated concrete can retard the formation of ice at -20 °C, exhibiting good anti-icing performance. [ABSTRACT FROM AUTHOR]

The construction of superhydrophobic surfaces necessitates the rational design of topographic surface structure and the reduction of surface energy. To date, the reported strategies are usually complex with multi-steps and costly. Thus, the simultaneous achievement of the two indispensable factors is highly desired, yet rather challenging. Herein, we develop a novel structure engineering strategy of realizing the fabrication of a functionally integrated device (FID) with a superhydrophobic surface via a one-step spraying method. Specifically, silica nanoparticles are used to control the surface roughness of the device, while polydimethylsiloxane is employed as the hydrophobic coating. Benefitting from the adopted superhydrophobicity, the as-fabricated FID exhibits a continuous, excellent oil-water separating performance (e.g., 92.5% separating efficiency) when coupled with a peristaltic pump. Notably, a smart design of incorporating a gas switch is adopted in this device, thereby effectively preventing water from entering the FID, realizing thorough oil collection, and avoiding secondary pollution. This work opens up an avenue for the design and development of the FID, accessible for rapid preparation and large-scale practical application. [ABSTRACT FROM AUTHOR]

Macroscopic supramolecular assembly (MSA) is a recent advance in supramolecular chemistry that involves associating large building blocks with a size larger than 10 µm through noncovalent interactions. However, until now the applicable material system is rather limited to hydrogels, and MSA of rigid materials with supramolecular interactions widely used in molecular assembly has rarely been reported due to the difficulty in achieving multivalency between rigid surfaces. Herein, the concept of flexible spacing coating is applied with highly flowable properties, and the electrostatic‐interaction‐driven MSA of relatively rigid polydimethylsiloxane building blocks is demonstrated. With the flexible spacing coating of a polyelectrolyte multilayer, the oppositely charged rigid building blocks can realize MSA under shaking in water for 5 min. The major contribution of the electrostatic interaction is confirmed by both qualitative controlled MSA experiments in other solvents, disassembly in ionic solution and quantitative results with an in situ force measurement method. Macroscopic supramolecular assembly (MSA) is a recent advance in supramolecular chemistry but currently limited to applicable materials and supramolecular interactions. This works demonstrates the first electrostatic‐interaction‐driven MSA of rigid building blocks based on the concept of flexible spacing coating, thus having broadened the applicable building blocks and extended practical application conditions of MSA. [ABSTRACT FROM AUTHOR]