The water repellency and self-cleaning properties of many plant surfaces have been qualitatively and sometimes quantitatively attributed to not only the chemical constituency of the cuticle covering their surface, which is composed by soluble lipids embedded in a polyester matrix, but, even more importantly, to the specially textured topography of the surface. [1][2][3] It is understood that the microstructrured rough surface enhances the effect of surface chemistry into superhydrophobicity, reduced particle adhesion and water repellency. Actually, in the cases of the most famous water repellent plant leaves like Nelumbo nucifera (the sacred Lotus) or Colocasia esculenta, a dual scale roughness has been observed on their surfaces created by papillose epidermal cells and an additional layer of epicuticular waxes. The roughness of the papillae leads to a reduced contact area between the surface and a liquid drop (or a particle) with droplets residing only on the tips of the epicuticular wax crystals on the top of the papillose epidermal cells. As a result, contaminating particles can be picked up by the liquid and carried away as the droplet rolls off the leaf; this was coined the ''Lotus Effect'' by Barthlott and Neinhuis, [1] who then organized a consortium trying to develop self-cleaning products.[4] Similar behavior has been observed on other biological surfaces like the wings of Cicada orni [5] or Rhinotermitidae [6] insects. A water repellent surface exhibits certain remarkable wetting characteristics originating from very high contact angles (in excess of 1508) and very small values of contact angle hysteresis (less than 58): [7] droplets roll down these surfaces at a speed faster than that of a solid sphere rolling under gravity, [8] they can fully bounce after impacting the surface [9,10] whereas the time of contact of an impacting droplet with the surface is independent of its velocity.[10]Water repellency was discovered very early when Boys noticed that water deposited on a lycopodium layer rolled itself up into perfect little balls.[11] However, it has attracted the interest of the scientific community over the last ten years following the observations of the microtextures of plant surfaces and the first development of super-water-repellent surfaces possessing a fractal microstructure; [12] the latter were created spontaneously when alkylketene dimmer was solidified from the melt. Water repellency as well as the development of super-hydrophobic surfaces are currently the focus of considerable research because of a range of potential applications, such as the development of self-cleaning surfaces, microfluidics, lab-on-chip devices, low friction coatings, water proof and anti-rain textiles, etc. [13][14][15] The actual strategy consists in mimicking superhydrophobic biosurfaces by designing rough substrates out of hydrophobic materials. [16,17] This has been implemented in a variety of bottom-up or bottom-down approaches [18] like deposition of functionalized particles [19][20][21][22]

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