Facile preparation of superamphiphobic phosphate–Cu coating on iron substrate with mechanical stability, anti-frosting properties, and corrosion resistance

We present a facile, low-cost, and fast method for preparing superamphiphobic surface with water contact angle and rapeseed oil contact angle of 160° and 153° on steel substrate. The fabrication process is composed of the phosphate, Cu co-deposition in phosphating bath and the low surface energy materials modification by 1H,1H,2H,2H-peruorodecyltriisopropoxysilane (FAS-17). Contact angle measurement, X-ray diffraction, scanning electron microscopy equipped with energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and electrochemical workstation were carried out to investigate the surface wettability, chemical composition, morphology, and anti-corrosion performance. Results show that the optimal CuSO₄·5H₂O concentration for the surface to achieve superamphiphobicity is 6 g L⁻¹, and the prepared surface exhibits excellent mechanical abrasion resistance on 600 grit SiC sand paper. Moreover, the dynamic frosting–defrosting experiments indicated that the surface has a good anti-frosting ability. The potentiodynamic polarization proves that the superhydrophobic surface can protect the steel substrate from corrosion solution. Meanwhile the surface also shows a good chemical stability under different pH values and excellent self-cleaning ability in both muddy water and lubricating oil.