All-organic superhydrophobic coating with anti-corrosion, anti-icing capabilities and prospective marine atmospheric salt-deliquesce self-coalesce protective mechanism

Abstract

Water-repellent and interfacial non-wetting superhydrophobicity has great potential to address corrosion/icing-induced material-deterioration problems. Herein, an all-organic superhydrophobic coating was constructed using facile and substrate-independent spray-coating method based on PTFE and PDMS . FE-SEM, EDS, and XPS techniques were used to analyze the surface topographies and chemical compositions. The coating exhibits superior anti-fouling and self-cleaning properties against various liquid and solid contaminants due to the synergic effect of low surface energy and hierarchical structures. The EIS and potentiodynamic polarization results show improved charge transfer resistance ( R ct ), positive shifted corrosion potential ( E corr ), and decreased corrosion current density ( I corr ), implying significantly enhanced anti-corrosion performance with 99.83 % inhibition efficiency. Besides, the delay rate of ice-freezing time of the coating is 232 % at −5°C, 137 % at −10 °C and 204 % at −15 °C compared with uncoated Q235 substrate respectively. The ice adhesion strength of the coating accounts for only 6.55 % at −5°C, 7.03 % at −10 °C and 9.35 % at −15 °C than that of the bare Q235 carbon steel, demonstrating ultra-low ice adhesion force and anti-icing capabilities. The hygroscopic and deliquesce behaviors of NaCl salt particles reveal an intriguing salt-deliquescence self-coalescence phenomenon and prospective anti-corrosion mechanism for superhydrophobic materials in high-humidity marine atmospheric environments.