Oil/water separation has recently become a global challenging task due to the frequent oil spill accidents and increasing industrial oily waste water. Here, we first demonstrate underwater superoleophobic palygorskite coated meshes, which were fabricated by spraying palygorskite and polyurethane mixtures on copper mesh substrates. The underwater superoleophobic meshes were then used to study gravity driven oil/water separation for a series of oil/water mixtures, where only the water from the oil/water mixture is allowed to permeate through the mesh. Separation efficiency up to 99.6 % could be achieved through the coated mesh for the kerosene-water mixture. In addition, the palygorskite coated mesh still maintained high separation efficiency over 99.0 % and stable recyclability after 50 separation cycles with the surface morphology of the palygorskite coated mesh nearly unchanged. Furthermore, the palygorskite coated meshes exhibit excellent environmental stability under a series of harsh conditions, which are used for the separation of the mixtures of oil and various corrosive and active aqueous solutions, including strong acidic, 2 alkaline, or salt aqueous solutions, even hot water. The fabrication approach presented here can be applied for coating large surface areas and to develop a large-scale oil/water separation facility for oil and various corrosive and active aqueous mixtures. Figure 2. FE-SEM images of (a) the original copper mesh and (b-c) the as-prepared palygorskite coated mesh surface at low and high magnifications, respectively. The inset (a) is the magnified image of the original mesh.

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Natural biominerals are formed through metastable amorphous precursor phases via a bottom-up, nanoparticle-mediated mineralization mechanism. Using an acid-etched human dentin model to create a layer of completely-demineralized collagen matrix, a bio-inspired mineralization scheme has been developed based on the use of dual biomimetic analogs. These analogs help to sequester fluidic amorphous calcium phosphate nanoprecursors and function as templates for guiding homogeneous apatite nucleation within the collagen fibrils. By adopting this scheme for remineralizing adhesive resin-bonded, completely-demineralized dentin, we have been able to redeposit intrafibrillar and extrafibrillar apatites in completely-demineralized collagen matrices that are imperfectly infiltrated by resins. This study utilizes a spectrum of completely- and partially-demineralized dentin collagen matrices to further validate the necessity for using a biomimetic analog-containing medium for remineralizing resin-infiltrated partially-demineralized collagen matrices in which remnant seed crystallites are present. In control specimens in which biomimetic analogs are absent from the remineralization medium, remineralization could only be seen in partially-demineralized collagen matrices probably by epitaxial growth via a top-down crystallization approach. Conversely, in the presence of biomimetic analogs in the remineralization medium, intrafibrillar remineralization of completely-demineralized collagen matrices via a bottom-up crystallization mechanism can additionally be identified. The latter is characterized by the transition of intrafibrillar minerals from an inchoate state of continuously-braided microfibrillar electron-dense amorphous strands to discrete nanocrystals, and ultimately into larger crystalline platelets within the collagen fibrils. Biomimetic remineralization via dual biomimetic analogs has the potential to be translated into a functional delivery system for salvaging failing resin-dentin bonds.

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crude oil that greatly harmed the coastline and near-shore water, killing huge populations of marine animals and plants.Various methods have been applied in oil spill cleanup such as mechanical collection, controllable burn, and chemical decomposition. [3][4][5] However, those techniques are time-consuming, environment unfriendly, and expensive. Recently, researchers prefer to design and fabricate functional membrane materials and adsorbents with special wettability for oil/ water separation, protecting environment from secondary pollution and reducing the loss. [6][7][8][9] Jiang and co-workers, for the fi rst time, fabricated a mesh fi lm possessing both superhydrophobic and superoleophilic properties to separate oil from water, exhibiting high oil/water separation effi ciency and selectivity. [ 10 ] Subsequently, abundant materials with both superhydrophobic and superoleophilic properties are generally applied to removal of oil from water, [11][12][13][14][15][16][17][18][19][20] such as metallic mesh-based materials, [21][22][23] sponges and foam-based materials, [24][25][26] ceramic microfi ltration membranes, [ 27 ] carbon-based materials, [ 28,29 ] oil-absorptive rubber, [ 30 ] fabrics, [31][32][33] etc. In general, these materials were obtained by roughening of their surfaces and posthydrophobization. Various approaches have been used to construct hierarchical rough structures needed for superhydrophobicity, such as a sol-gel method, [ 34 ] chemical vapor deposition, [ 35 ] hydrothermal method, [ 36 ] electrochemical method, [ 37 ] spray method, [ 38,39 ] and so forth. Nevertheless, most of the methods involved in fabricating superhydrophobic surfaces have limitations for large-scale fabrication, due to complicated processes, sophisticated equipment, and low commercial availability of raw materials. In addition, the traditional fi lterable materials cannot easily be applied in oil spills, because they need to gather polluted water fi rst and then fi lter it. Therefore, it is imperative to fi nd high-performance absorbent materials for the removal of large amounts of oil pollutant from the water surface.Recently, superhydrophobic/superoleophilic 3D sponges have received considerable attention due to their rapid absorption Removal of oil from water has become an increasingly important fi eld due to the frequent oil spill accidents as well as industrial oily wastewater. In this study, a bag is made from superhydrophobic fabric and stuffed with pristine polyurethane (PU) sponge just utilizing the synergetic effect of the superhydrophobic and superoleophilic selective absorption of oil from water of the fabric and the excellent large volume-based oil storage capacity of the PU sponge. The superhydrophobic fi lling bag can quickly absorb and collect a large amount of oil from a polluted water surface with the separation effi ciency always above 98.2% % for a series of oil/water mixtures. In addition, the fi lled orignial sponges exhibit large volume-based absorption capacity up to 20-36 times its own weight, ke...

A simple method was used to generate colorful hydrophobic stearate particles via chemical reactions between inorganic salts and sodium stearate. Colored self-cleaning superhydrophobic coatings were prepared through a facile one-step spray-coating process by spraying the stearate particle suspensions onto stainless steel substrates. Furthermore, the colorful superhydrophobic coating maintains excellent chemical stability under both harsh acidic and alkaline circumstances. After being immersed in a 3.5 wt % NaCl aqueous solution for 1 month, the as-prepared coatings remained superhydrophobic; however, they lost their self-cleaning property with a sliding angle of about 46 ± 3°. The corrosion behavior of the superhydrophobic coatings on the Al substrate was characterized by the polarization curve and electrochemical impedance spectroscopy (EIS). The electrochemical corrosion test results indicated that the superhydrophobic coatings possessed excellent corrosion resistance, which could supply efficient and long-term preservation for the bare Al substrate.

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In this work, a facile and inexpensive one-step sonochemistry irradiation method was developed for the fabrication of SiO2 nanoparticles functionalized with octadecyltrimethoxysilane and their in situ incorporation into cotton fabrics. The double sides of as-prepared fabrics show both superhydrophobic and superoleophilic properties simultaneously with a high water contact angle of 159 ± 1° and an oil contact angle of 0°. Thus, it can be used to separate and capture a series of oils from water, like kerosene, toluene and chloroform, etc. In addition, the as-prepared fabrics still have superhydrophobicity with a water contact angle of above 150° after 40 separation cycles with the separation efficiency for the kerosene-water mixture always above 94.6%. More importantly, the as-prepared fabrics showed robust and stable superhydrophobic properties towards hot water, many corrosive solutions (acidic, basic, salt liquids) and mechanical abrasion. Therefore, this reported fabric has the advantages of scalable fabrication, high separation efficiency, stable recyclability, and excellent durability, exhibiting the strong potential for industrial production.