The introduced method of electrodepositing robust network-like MH layer made the further application of low-cost superhydrophobic surface with magnesium hydroxide possible.ĭepuis la restriction de l’utilisation de composés à base de chrome (VI) par une directive européenne (Directive 2000/53/CE), en raison de sa toxicité élevée vis-à-vis de l’environnement, les composés à base de terre rare tel que l’oxyde de cérium ont été beaucoup privilégiés en tant qu’alternatifs compatibles avec les normes environnementales et présentant des propriétés comparables à celles des traitements conventionnels à base de Cr(VI) sur de nombreux alliages métalliques. The inhibition efficiency of the layer reached 99.03%, due to its extremely high corrosion resistance (Rct = 2.87 × 10⁵ Ω/cm², Rf = 2.53 × 10⁶ Ω/cm²). The layer also demonstrated good long-term immersion stability, and was still superhydrophobic with 72 h immersion in 3.5 wt% NaCl aqueous solution at room temperature. The robust layer kept superhydrophobic until 600 mm abrasion length facing 1000 grit SiC sandpaper under 100 g weight, and with detachment less than 5% after cross hatch tape adhesion test. sliding angle, 2.2°) and self-cleaning property after stearic acid modification. The magnesium hydroxide layer fabricated at the optimum condition (0.5 mol/L magnesium nitrate, 4 mg/L XG, 4 mg/L glucose, 2.6 pH value and 35 mA at 15☌ for 20 min) was with network-like structure, and exhibited excellent superhydrophobicity (water contact angle, 153.56°. Electrodeposition factors such as concentrations of xanthan gum and glucose, bath temperature, pH value of electrolyte and current intensity were studied. In this work, we electrodeposited a robust network-like magnesium hydroxide layer on iron substrate under the structure direction of xanthan gum which formed network with helical conformation at low temperature and proper pH value in aqueous solution. However, magnesium hydroxide superhydrophobic surfaces prepared through traditional electrodeposition method was always fragile and easy to peel off substrate, due to the discontinuous platelet-like structure which led to weak mechanical property. Superhydrophobic surface fabricated with magnesium hydroxide was safe, environment friendly, and of very low cost. Magnesium hydroxide is an innocuous, antibacterial, eco-friendly, and especially cheap material. Comparison with morphologies of deposits obtained by electrodepositions from aqueous magnesium salt electrolytes was also made and discussed.Įconomic cost of raw materials has become an important limiting factor for the further application of superhydrophobic surface. It is shown that the growth of the needles occurs under the conditions of predominant spherical diffusion control, while the contribution of the cylindrical diffusion to the final shapes was negligible. Mechanism of formation of the flower-like forms has been elucidated applying the general theory of disperse deposits formation which is based on the concept of local (spherical and cylindrical)diffusion fields. Aside from that, holes formed from detached hydrogen bubbles of various shapes and sizes, from dish-like holes to those resulting in honeycomb-like structures were also observed. The flower-like forms constructed from very thin needles with sharp tips were predominately formed by electrodeposition at various current densities and with various amounts of electricity. Morphologies of the produced deposits were characterized by scanning electron microscopy (SEM)technique. The structure of the formed particles was examined by X-ray diffraction (XRD), which revealed formation of MgO/Mg(OH) 2 mixture by molten salt electrolysis. ![]() The processes of electrodeposition from magnesium nitrate hexahydrate melt by galvanostatic regime of electrolysis have been analyzed.
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