Biomimetic fabrication of robust self-assembly superhydrophobic surfaces with corrosion resistance properties on stainless steel substrate

Abstract

A reed leaf-like superhydrophobic stainless surface is obtained by nanosecond laser direct writing. Through investigating the coupling interaction between the laser fluence and the overlapping rate, we fabricate biomimetic reed leaf-like structures on the stainless steel. This biomimetic structures reveal excellent superhydrophobicity with a water contact angle of 157 ± 1° and a sliding angle of 1 ± 0.5° after FAS-17 (1H,1H,2H,2H-perfluorodecyltriisopropoxysilane) modification. The superhydrophobicity of the as-prepared surface results from its biomimetic hierarchical micro-nanostructure and the grafted low-surface-energy fluorosilane. The superhydrophobic surface exhibits high microhardness and excellent mechanical abrasion resistance. It can maintain superhydrophobicity after sandpaper abrasion against 260 grit Al₂O₃ sandpaper for 2.5 m at the applied pressure of 12.5 kPa. Moreover, the superhydrophobic surface has good chemical stability in both acidic and alkaline environments. The Tafel polarization curves show that the as-prepared superhydrophobic surface has better corrosion resistance than the bare stainless steel surface. It is believed that this stainless superhydrophobic surface may have important significance in the practical application.