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In this review, we report on superhydrophobic and superoleophobic properties found in nature, which are strongly expected to benefit various potential applications. Mimicry of nature is the easiest way to reproduce such properties because nature has for millennia produced plants, insects and animals able to repel water as well as low surface tension liquids such as oils. The most famous example is the lotus leaf, but we may also consider insects able to walk on vertical surfaces or on the water surface, insects with colored structured wings or insects with antifogging and anti-reflective eyes. Most of the time, nature produces nanostructured waxes to obtain superhydrophobic properties. Very recently, the repellency of oils has been reported in springtails, for example. While several publications have reported the fabrication of superoleophobic surfaces using re-entrant geometry, in all of these publications fluorinated compounds were used because they have high hydrophobic properties but also relatively important oleophobic properties in comparison to hydrocarbon analogs even if they are intrinsically oleophilic. However, nature is not able to synthesize fluorinated compounds. In the case of the springtails, the surface structures consists of regular patterns with negative overhangs. The chemical composition of the cuticles is composed of three different layers: an inner cuticle layer made of a lamellar chitin skeleton with numerous pore channels, an epicuticular structures made of structural proteins such glycine (more than 50%), tyrosine and serine an the topmost envelope composed of lipids such as hydrocarbon acids and esters, steroids and terpenes. This discovery will help the scientific community to create superoleophobic materials without the use of fluorinated compounds.

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International audienceThe synthesis, reactivity and applications of glycerol carbonate (glycerine carbonate or 4-hydroxymethyl- 2-oxo-1,3-dioxolane) are discussed and reviewed. Supported by the increasing sustainable awareness, glycerol carbonate has gained much interest over the last 20 years because of its versatile reactivity and as a way to valorize waste glycerol. Numerous synthesis pathways for this molecule were identified, some of them very promising and on the verge of being applied at an industrial scale. The wide reactivity of this molecule due to the presence of both a hydroxyl group and a 2-oxo-1,3-dioxolane group has been studied and has initiated some emerging applications in various domains from solvents to polymers

International audienceThis review allows to give an overview of recent advances in the potential applications of superhydrophobic materials. Such properties are characterized by extremely high water contact angle and various adhesion properties. The conception of superhydrophobic materials has been possible by studying and mimicking natural surfaces. Now, extremely various applications have emerged such as anti-icing, anti-corrosion and anti-bacteria coatings, microfluidic devices, textiles, oil/water separation, water desalination/purification, optical devices, sensors, batteries and catalysts. At least two parameters were found to be essential for application: the presence of air on superhydrophobic materials with self-cleaning properties (Cassie-Baxter state) and the robustness of the superhydrophobic properties (stability of the Cassie-Baxter state). This review will allow to researchers to envisage new ideas and to industrialists to advance in the commercialization of these materials

This review is an exhaustive representation of the electrochemical processes reported in the literature to produce superhydrophobic surfaces. Due to the intensive demand in the elaboration of superhydrophobic materials using low-cost, reproducible and fast methods, the use of strategies based on electrochemical processes have exponentially grown these last five years. These strategies are separated in two parts: the oxidation processes, such as oxidation of metals in solution, the anodization of metals or the electrodeposition of conducting polymers, and the reduction processed such as the electrodeposition of metals or the galvanic deposition. One of the main advantages of the electrochemical processes is the relative easiness to produce various surface morphologies and a precise control of the structures at a micro- or a nanoscale.

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Natural surfaces can be superhydrophobic, but on the other hand, superoleophobic properties are extremely rare. We demonstrate that modification of the 3,4-alkylenedioxy bridge length in pyrrole-derivative monomers can have a dramatic influence on the superoleophobic properties of electrodeposited conductive polymers. Here we report the synthesis and characterization of novel fluorinated 3,4-ethylenedioxypyrrole (EDOP) and 3,4-propylenedioxypyrrole (ProDOP) monomers and their corresponding electrodeposited polymers. The polymer surfaces were characterized by static and dynamic contact angle measurements, scanning electron microscopy, and cyclic voltammetry. Surprisingly, the antiwetting properties do not depend of the fluorocarbon chain length (F-octyl to F-hexyl) but are in fact governed by the nature of the electrochemically deposited core. Indeed, superhydrophobic and superoleophobic surfaces with extremely low hysteresis and sliding angles for water droplets were obtained by electrochemical polymerization of highly fluorinated EDOP, whereas highly fluorinated ProDOP gave only superhydrophobic surfaces with a sticky behavior. The difference in wettability is attributed to surface nanoporosity resulting from the doping process.