Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore.
ACS Appl Mater Interfaces. 2017 Mar 8;9(9):8354-8360. doi: 10.1021/acsami.6b14631. Epub 2017 Feb 21.
Low surface tension sebaceous liquids such as human fingerprint oils are readily deposited on high energy surfaces such as clean glass, leaving smudges that significantly lower transparency. There have been several attempts to prevent formation of these dactylograms on glass by employing oil-repellent textured surfaces. However, nanotextured superoleophobic coatings typically scatter visible light, and the intrinsic thermodynamic metastability of the composite superoleophobic state can result in failure of the oil repellency under moderate contact pressure. We develop titania-based porous nanoparticle coatings that are superoleophilic and highly transparent and which exhibit short time scales for decomposition of fingerprint oils under ultraviolet light. The mechanism by which a typical dactylogram is consumed combines wicking of the sebum into the nanoporous titania structure followed by photocatalytic degradation. We envision a wide range of applications because these TiO nanostructured surfaces remain photocatalytically active against fingerprint oils in natural sunlight and are also compatible with flexible glass substrates.
低表面能的皮脂液体，如人类指纹油，很容易沉积在高能表面，如清洁的玻璃上，留下污迹，显著降低透明度。已经有几种方法试图通过使用防油纹理表面来防止指纹在玻璃上形成。然而，纳米纹理的超疏油涂层通常会散射可见光，而且复合超疏油状态的固有热力学亚稳性可能导致在中等接触压力下防油性能失效。我们开发了基于二氧化钛的多孔纳米颗粒涂层，具有超亲油性和高透明度，并在紫外光下表现出指纹油分解的短时间尺度。典型指纹被消耗的机制是皮脂被吸入纳米多孔二氧化钛结构，然后进行光催化降解。我们设想了广泛的应用，因为这些 TiO 纳米结构表面在自然光下对指纹油仍然具有光催化活性，并且与柔性玻璃基底兼容。
