Key Laboratory of Marine Environmental Corrosion and Bio-Fouling, Institute of Oceanology , Chinese Academy of Sciences , Qingdao 266071 , China.
Open Studio for Marine Corrosion and Protection , Pilot National Laboratory for Marine Science and Technology (Qingdao) , Qingdao 266237 , China.
ACS Appl Mater Interfaces. 2019 Oct 16;11(41):38276-38284. doi: 10.1021/acsami.9b11415. Epub 2019 Oct 7.
Coalescence-induced droplet jumping behavior of superhydrophobic surfaces has attracted increasing attention for condensation heat transfer, antifrosting, self-cleaning, and electrostatic energy harvesting applications. The potential of applying such functionalized behavior for atmospheric corrosion protection, however, is unknown. Herein, we experimentally demonstrate, for the first time, the feasibility of applying coalescence-induced droplet jumping behavior of a superhydrophobic surface for atmospheric corrosion protection. Based on the rational fabrication of two kinds of superhydrophobic surfaces that are advantageous and not advantageous for coalescence-induced droplet jumping behavior, we reveal a novel atmospheric corrosion protection mechanism by studying the correlations of the surface structure, droplet jumping behavior, and atmospheric corrosion resistance of the two surfaces. Our results demonstrate that the superhydrophobic surface with coalescence-induced droplet jumping behavior presents a better atmospheric corrosion resistance than the superhydrophobic surface without coalescence-induced droplet jumping behavior. This is because coalescence-induced droplet jumping behavior of the superhydrophobic surface offers a possible mechanism to switch the droplets from a partial wetting state to the mobile Cassie state, and this switch is critical for facilitating the recovery of the air film trapped in the microstructure of a surface. In particular, the recovered air film enhances the atmospheric corrosion resistance of a superhydrophobic surface due to its barrier-like character. The insights gained from this work not only open a new avenue for designing first-rank anticorrosion materials but also offer new opportunities for understanding the physics of jumping droplets in other promising applications.
超疏水表面的合并诱导液滴跳跃行为在冷凝传热、防霜、自清洁和静电能量收集等应用中引起了越来越多的关注。然而，这种功能化行为在大气腐蚀防护方面的应用潜力尚不清楚。在此，我们首次实验证明了超疏水表面的合并诱导液滴跳跃行为在大气腐蚀防护中的应用是可行的。基于对两种超疏水表面的合理制备，这两种表面有利于和不利于合并诱导液滴跳跃行为，我们通过研究这两种表面的表面结构、液滴跳跃行为和大气腐蚀性之间的相关性，揭示了一种新的大气腐蚀防护机制。我们的结果表明，具有合并诱导液滴跳跃行为的超疏水表面比不具有合并诱导液滴跳跃行为的超疏水表面具有更好的大气腐蚀性。这是因为超疏水表面的合并诱导液滴跳跃行为提供了一种可能的机制，可以将液滴从部分润湿状态切换到可移动的 Cassie 状态，这种切换对于促进被困在表面微结构中的空气膜的恢复至关重要。特别是，恢复的空气膜由于其屏障特性增强了超疏水表面的大气腐蚀性。这项工作的见解不仅为设计一流的防腐材料开辟了新途径，也为理解其他有前途的应用中跳跃液滴的物理特性提供了新的机会。
