A self-healing superamphiphobic coating for efficient corrosion protection of magnesium alloy

Xia Zhao; Jinfei Wei; Bucheng Li; Sibei Li; Ning Tian; Lingyun Jing; Junping Zhang

doi:10.1016/j.jcis.2020.04.097

A self-healing superamphiphobic coating for efficient corrosion protection of magnesium alloy

J Colloid Interface Sci. 2020 Sep 1:575:140-149. doi: 10.1016/j.jcis.2020.04.097. Epub 2020 Apr 24.

Authors

Xia Zhao¹, Jinfei Wei², Bucheng Li³, Sibei Li⁴, Ning Tian⁵, Lingyun Jing¹, Junping Zhang⁶

Affiliations

¹ Department of Chemical Engineering, College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, PR China.
² Department of Chemical Engineering, College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050, PR China; Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000 Lanzhou, PR China.
³ Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000 Lanzhou, PR China.
⁴ Department of Physics, Beijing Normal University, Beijing 100875, PR China.
⁵ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, PR China; Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000 Lanzhou, PR China.
⁶ Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, PR China; Center of Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000 Lanzhou, PR China. Electronic address: jpzhang@licp.cas.cn.

PMID: 32361230
DOI: 10.1016/j.jcis.2020.04.097

Abstract

Magnesium alloys have many excellent properties, but the poor corrosion resistance seriously hinders their widespread applications. Here, we report a self-healing superamphiphobic coating for efficient corrosion protection of magnesium alloy by the combination of a compact self-healing epoxy resin (SHEP) coating and a porous superamphiphobic coating. The coating shows (i) excellent superamphiphobicity with high contact angle, low sliding angle and robust impact/bounce behavior, (ii) excellent anti-corrosion performance as demonstrated by the potentiodynamic polarization curves and electrochemical impedance spectroscopy, and (iii) excellent self-healing performance as proved by the scanning electron microscopy and electrochemical impedance spectroscopy. This is owing to synergistic effect of the bi-layer structure. Furthermore, the healed coating retained excellent anti-corrosion performance according to the immersion test and neutral salt spray test. This is because the SHEP layer can effectively drive repair of microstructure of the superamphiphobic layer, and then recover of superamphiphobicity. Therefore, the contact area and contact time of corrosive solutions with the pristine and healed coatings are limited, which efficiently prevents diffusion of corrosive substances such as water, chloride ions and oxygen. The self-healing superamphiphobic coating may find applications in protection of various metal alloys.

Keywords: Corrosion; Self-healing; Shape memory; Superamphiphobic; Superhydrophobic.