Engineering PDMS/paraffin solid slippery surfaces for superior corrosion resistance

This work investigates solid slippery surface with varying PDMS/paraffin volume ratios to address condensate-induced corrosion on Q235 steel in marine atmospheric environments. Wettability tests, water mist condensation experiments, electrochemical measurements, and COMSOL simulations were conducted to evaluate droplet dynamics and corrosion protection. Results show that increasing the PDMS ratio reduces sliding angle and promotes droplet detachment. Under condensation, high PDMS ratio (9:1) samples facilitate timely droplet shedding, reducing surface residence time and corrosion risk, whereas low PDMS ratio samples exhibit persistent wetting detrimental to anticorrosion. Electrochemical tests reveal that higher PDMS ratios decrease corrosion current density and increase impedance modulus and charge transfer resistance, with the 9:1 sample showing optimal performance. COMSOL simulations confirm that high PDMS ratio samples have smaller effective electrochemical exposure area, stronger interfacial shielding, and shorter droplet residence time. Collectively, tuning the PDMS/paraffin volume ratio effectively enhances the anticorrosion performance of solid slippery surface, offering a promising strategy for protective coatings in harsh marine environments.