Innovative droplet manipulation techniques on F-L@KH550/HDTMS/ PDMS/SiO2 superhydrophobic surfaces with excellent corrosion resistance using femtosecond laser and chemical modifications

Surface droplet manipulation is critical for various applications in biomedical engineering, chemical synthesis, and environmental monitoring. This study presents an innovative strategy for fabricating highly adhesive and manipulable superhydrophobic surfaces on aluminum alloys by combining femtosecond laser etching with multilayer chemical modifications. A micro-nano hierarchical structure is generated through precise femtosecond laser processing, followed by chemical treatments using gamma-aminopropyltriethoxysilane (KH550), hexadecyltrimethoxysilane (HDTMS), Polydimethylsiloxane (PDMS), and silicon dioxide (SiO2) nanoparticles. The resulting surface exhibits remarkable superhydrophobicity, with a water contact angle of 165.92 degrees, and demonstrates excellent long-term corrosion resistance in saline environments. Electrochemical corrosion tests revealed that the corrosion current density of the superhydrophobic surface is reduced by two orders of magnitude compared to untreated aluminum, achieving a corrosion inhibition efficiency of 96.60 %. This outstanding corrosion resistance is attributed to the formation of a stable passivation layer that effectively inhibits the penetration of corrosive agents, ensuring sustained protection over extended periods. The surface enables droplet rewriting, transfer, and microchemical reactions, and exhibits reversible wettability changes under thermal influence. These properties position the surface as a versatile platform for applications in selective droplet storage, microreactors, and dynamic liquid transport systems, particularly in environments requiring enhanced durability and long-term performance.