Enhanced low-temperature radiative cooling and marine durability of stainless steel with a novel multi-layered composite coating

In marine environments, managing heat dissipation and corrosion resistance is critical for the longevity of 304 stainless steel, particularly in electronic devices exposed to high temperatures or operational speeds. This study addresses the challenge of enhancing the durability of 304 stainless steel under such conditions by developing a novel composite coating-Superhydrophobic/ZIF-8@CNT/high-entropy alloy (SZCP). The coating was applied to the steel using physical vapor deposition followed by ultrasonic spraying, consisting of a TiVCrAlCu high-entropy alloy film and a superhydrophobic ZIF-8@CNT layer. This innovative approach enhances the steel's thermal emissivity and radiative heat dissipation, as evidenced by the SZCP-coated materials maintaining temperatures up to 12 °C cooler than uncoated steel within 85 s. Electrochemical tests confirmed the high-entropy alloy film as an effective corrosion barrier, while the ZIF-8@CNT layer improved electrochemical stability, reducing the corrosion current density by 98.87 % and lowering the corrosion rate to 0.47 mm/year. Furthermore, treatment with Trimethoxy (1H, 1H, 2H, 2H-heptadecafluorodecyl) silane (FAS17) imparted self-cleaning properties to the coating, achieving contact angles over 150° and sliding angles below 3°, effectively reducing contamination from substances like sand and yogurt. This research introduces a strategic approach to improve the heat dissipation, self-cleaning, and corrosion resistance of metal substrates in challenging environments, offering significant potential for industrial applications.