Department of Nature-Inspired Nanoconvergence Systems, Korea Institute of Machinery and Materials, 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon 34103, Republic of Korea.
School of Mechanical Engineering, Sungkyunkwan University, 2066, Seobu-Ro, Jangan-Gu, Suwon 16419, Gyeonggi-Do, Republic of Korea.
ACS Nano. 2020 Aug 25;14(8):10198-10209. doi: 10.1021/acsnano.0c03463. Epub 2020 Jul 31.
Slippery liquid-infused porous surfaces (SLIPSs) have been actively studied to improve the limitations of superhydrophobic (SHP) surfaces, especially the defects of the nonwetting chemical coating layer and the weak mechanical robustness of surface micro/nanostructures. However, the SLIPSs also have several drawbacks including volatilization and leakage of lubricant caused by long-term usage. In this study, we suggest the use of icephobic, highly transparent, and self-healing solid slippery surface to overcome the limitations of both surfaces (SLIPS and SHP) by combining specific biomimetic morphology and intrinsic properties of paraffin wax. A moth-eye mimicking nanopillar structure was prepared instead of a porous structure and was coated with solid paraffin wax for water repellence. Moth-eye structures enable high surface transparency based on antireflective effect, and the paraffin layer can recover from damage due to sunlight exposure. Furthermore, the paraffin coating on the nanopillars provides an air trap, resulting in a low heat transfer rate, increasing freezing time and reducing adhesion strength between the ice droplet and the surface. The heat transfer model was also calculated to elucidate the effects of the nanopillar height and paraffin layer thickness. The antireflection and freezing time of the surfaces are enhanced with increase in nanopillar height. The paraffin layer slightly deteriorates the transmittance but enhances the icephobicity. The solar cell efficiency using a biomimetic solid slippery surface is higher than that of bare glass due to the antireflective effect. This integrated biomimetic solid slippery surface is multifunctional due to its self-cleaning, anti-icing, antireflection, and self-healing properties and may replace SLIPS and SHP surfaces.
滑液浸润多孔表面（SLIPS）已被积极研究以改善超疏水（SHP）表面的局限性，特别是非润湿化学涂层层的缺陷和表面微/纳米结构的弱机械鲁棒性。然而，SLIPS 也有几个缺点，包括由于长期使用导致的润滑剂蒸发和泄漏。在这项研究中，我们建议使用具有抗冰性、高透明性和自修复性的固体滑爽表面，通过结合特定的仿生形态和石蜡的固有特性来克服两种表面（SLIPS 和 SHP）的局限性。模仿蛾眼的纳米柱结构代替多孔结构，并用固体石蜡涂覆以实现拒水。蛾眼结构基于抗反射效应实现了高表面透明度，并且石蜡层可以从阳光暴露造成的损坏中恢复。此外，纳米柱上的石蜡涂层提供了空气陷阱，导致热传递率低，冻结时间延长，冰滴与表面之间的粘附强度降低。还计算了传热模型以阐明纳米柱高度和石蜡层厚度的影响。随着纳米柱高度的增加，表面的抗反射和冻结时间都得到了增强。石蜡层略微降低了透光率，但增强了抗冰性。由于抗反射效应，使用仿生固体滑爽表面的太阳能电池效率高于裸玻璃。这种集成的仿生固体滑爽表面具有自清洁、抗结冰、抗反射和自修复等多种功能，可能取代 SLIPS 和 SHP 表面。
