Super-hydrophobic surface on pure magnesium substrate by wet chemical method

A layer of flower-like super-hydrophobic film was fabricated on pure Mg surface by chemical etching in H(2)SO(4), H(2)O(2) and subsequent immersion in stearic acid (CH(3)(CH(2))(16)COOH) ethanol solution. The superhydrophobic surface showed a static water contact angle of 154 degrees with the sliding angle of about 3 degrees. With scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and Fourier-transform infrared (FT-IR) spectrometer, the microstructure and composition of the sample were analyzed. Results showed that the flower-like structure and the bonding of the CH(3)(CH(2))(16)COO on Mg surface can be responsible for the superior water-repellent property. Electrochemical impedance spectroscopy revealed that the transfer resistance of super-hydrophobic surface was increased about four times than bare Mg after one-hour immersion in 0.1 mol/L NaCl solution. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.