Efficient dual defense: PDA-Cu coating for simultaneous corrosion resistance and antibacterial protection of Mg alloys

The corrosion problem of Mg alloys remains a significant barrier to their technical applications. Particularly challenging is meeting specific functional requirements while enhancing corrosion resistance. Here, a novel metal organic composite coating (PDA-Cu) has been developed, exhibiting excellent corrosion resistance, strong bonding strength, and potent antibacterial properties. In 3.5 wt% NaCl solution, the corrosion rate of PDA-Cu alloy was significantly lower than that of bare Mg alloy, about 1/360; it had a strong inhibition rate (100%) and high binding strength (23.75 N). Importantly, the composite coating maintains consistency across various substrates and forms, proving its adaptability and expanding its potential applications.