Temperature Dependent Switchable Superamphiphobic Coating on Steel Alloy Surface

Water and oil repellence from surface of steel to increase its lifetime and efficiency has shown a great interest in todays\u27 research. In this work, superamphiphobic coating on steel surface was synthesized by employing drop casting technique using 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane (PFOTS) and silica (SiO2) nanoparticles. Surface morphological analysis confirms the presence of overhanging microstructures on the coated surface and it shows the super repellency to low surface tension liquid hexadecane (γ = 27 mN/m). Its superamphiphobic property is also maintained after annealing in temperature range from 25 to 350 °C; however, annealing of coating at higher temperature degrades —CF2 and —CF3 functional group and superamphiphobicity turns into superhydrophobicity. Additionally coating shows excellent chemical stability. Further, abrasion, adhesion, liquid jet impact and bending tests show the good mechanical durability of coating. Furthermore, the coating also exhibits excellent self-cleaning property. The aforesaid stable superamphiphobic steel surfaces have potential industrial applications