Wetting transparency of graphene
Wetting transparency of graphene
复制标题
DOI：
10.1038/nmat3228
复制
发表时间：
2012-03-01
期刊：
影响因子：
41.2
通讯作者：
Koratkar, Nikhil A.
中科院分区：
文献类型：
--
作者：
Rafiee, Javad;Mi, Xi;Koratkar, Nikhil A.
我们报告说，石墨烯涂层不会显著破坏表面的固有润湿行为，因为表面与水的相互作用是由范德华力主导的。我们的接触角测量表明，石墨烯单层对铜、金或硅是湿润透明的，但对玻璃则不是，因为玻璃的润湿性主要是由短程化学键决定的。随着石墨烯层数的增加，铜与水的接触角逐渐向体积石墨值过渡，达到类似6层石墨烯的水平。分子动力学模拟和理论预测证实了我们的测量结果，并表明石墨烯的湿润透明度与其极薄有关。我们还发现，由于石墨烯涂层能够在不破坏表面固有润湿性的情况下抑制铜的氧化，铜上的冷凝传热增加了30-40%。这种独立调整表面特性而不破坏其润湿响应的能力，可能对导电、保形和不渗透表面涂层的设计具有重要意义。
We report that graphene coatings do not significantly disrupt the intrinsic wetting behaviour of surfaces for which surface-water interactions are dominated by van der Waals forces. Our contact angle measurements indicate that a graphene monolayer is wetting-transparent to copper, gold or silicon, but not glass, for which the wettability is dominated by short-range chemical bonding. With increasing number of graphene layers, the contact angle ofwater on copper gradually transitions towards the bulk graphite value, which is reached for similar to 6 graphene layers. Molecular dynamics simulations and theoretical predictions confirm our measurements and indicate that graphene's wetting transparency is related to its extreme thinness. We also show a 30-40% increase in condensation heat transfer on copper, as a result of the ability of the graphene coating to suppress copper oxidation without disrupting the intrinsic wettability of the surface. Such an ability to independently tune the properties of surfaces without disrupting their wetting response could have important implications in the design of conducting, conformal and impermeable surface coatings.