锌合金表面疏水ZIF-67膜的制备及其耐腐蚀性研究

Study on Preparation and Corrosion Resistance of Hydrophobic ZIF-67 Film on Zn Alloy Surface

通过溶剂热合成方法,在锌合金表面制备了具有耐腐蚀性的ZIF-67膜.用X-射线衍射和扫描电镜对膜的晶体结构和表面形貌进行表征.通过接触角测量对合成膜表面的疏水性进行测定,结果表明:合成膜的接触角大于90°,说明合成的膜表面具有疏水性能.动电位极化测试显示疏水膜的存在降低了锌合金的腐蚀电流密度,交流阻抗谱的测试结果也显示了疏水ZIF-67膜可以提高锌合金在NaCl溶液中的耐腐蚀性.采用划格法测定了疏水膜与基体间的结合力.根据附着力GB/T 9286—1998的分类标准,ZIF-67膜的附着力可以定为0级,说明ZIF-67膜与基体间有良好的结合力.

A ZIF-67film with corrosion resistance was prepared on the surface of Zn alloy by solvent thermal method.The crystal structure and surface morphology of the ZIF-67film were characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM),respectively.The hydrophobic property of the film was tested by water contact angle(CA)measurement.The results showed that the contact angle of the film was larger than90°,which indicated that the surface had hydrophobicity.The potentiodynamic polarization test indicated that the existence of hydrophobic film reduced the corrosion current density of the Zn alloy.The results of AC impedance spectroscopy also showed that hydrophobic ZIF-67film can improve the corrosion resistance of Zn alloy in NaCl solution.The adhesion of hydrophobic film was investigated through cross-cut test.According to the classification of the adhesion given in GB/T9286-1998,the results indicated that the adhesion of the ZIF-67film can be classified as grade0,which indicated that ZIF-67film has good adhesion with matrix.