Fabrication of cross-like ZIF-L structures with water repellency and self-cleaning property via a simple in-situ growth strategy

Inspired by the "lotus effect'', more and more attention has been paid to the water repellent and self-cleaning surface. Due to its excellent properties, Mg alloy is considered to be one of the most promising engineering materials so far. However, the humid and corrosive environment makes Mg alloy susceptible to corrosion, which greatly limits its wide application. So it is very necessary to improve the properties of Mg alloy through surface treatment. Because of good chemical stability, thermostability and easy preparation, Zeolitic Imidazolate Frameworks (ZIFs) materials have been applied in the field of superhydrophobicity. In addition, in-situ growth has advantages of simple method, convenient operation and no need for expensive experimental equipment. Therefore, in this work, the superhydrophobic coating with cross-like Zeolitic Imidazolate Framework-L (ZIF-L) structure is fabricated on Mg alloy surface via a simple in-situ growth and low energy modification. The superhydrophobic ZIF-L coating on the Mg alloy substrate has excellent water repellency and self-cleaning property, and the stability test results show that it has good performance in thermostability and durability. Besides, the coating keeps superhydrophobic state after being immersed in an alkaline solution for 112 h, showing excellent resistance to alkaline solution. Therefore, the superhydrophobic coating prepared in this work can expand the application of Mg alloy in different service environments and provide a novel way for Mg alloy applying into more fields.