Fabrication of a superhydrophobic Mg-Mn layered double hydroxides coating on pure magnesium and its corrosion resistance

A superhydrophobic coating based on a Mg-Mn LDHs film was fabricated on pure Mg by an in-situ growth method and chemical modification by adsorption of myristic acid (MA, CH3(OH2)(12)COOH). The static contact angle of the superhydrophobic surface was about 152.2 degrees. The structure and composition of the samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The corrosion resistant performance of the samples in simulated body fluid (SBF) was investigated by electrochemical impedance spectroscopy (EIS). The impedance of the superhydrophobic coating sample at low frequency is approximately 20,000 Omega.cm(2) which is more than twice of that of the LDHs film and ten times of that of pure Mg substrate. The superhydrophobic coating can effectively protect the Mg from corrosion in SBF for a long time.