Effects of Layering and Supporting Substrate on Liquid Slip at the Single-Layer Graphene Interface
Effects of Layering and Supporting Substrate on Liquid Slip at the Single-Layer Graphene Interface
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DOI：
10.1021/acsnano.1c01884
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发表时间：
2021-06-11
期刊：
影响因子：
17.1
通讯作者：
Espinosa-Marzal, Rosa M.
中科院分区：
文献类型：
--
作者：
Greenwood, Gus;Kim, Jin Myung;Espinosa-Marzal, Rosa M.
了解液体分子沿沿着石墨烯表面滑动的调制对于二维材料的许多有前景的应用（例如传感器、纳米流体装置和生物系统）是至关重要的。在这里，我们使用原子力显微镜（AFM）的力测量直接测量流体动力学，溶剂化，和摩擦力沿着石墨烯平面在七种液体。结果表明，较大的滑移长度与液体分子的界面有序性有关，这表明形成多层的液体的有序性促进了滑移。这种现象似乎比传统上假设的石墨烯的润湿行为或固液相互作用能更相关。此外，液体沿着石墨烯平面的滑移边界条件对石墨烯下面的衬底敏感，表明下面的衬底影响石墨烯与液体分子的相互作用。由于界面滑移可以对压降、通过纳米通道的电和扩散传输以及润滑产生显著影响，因此这项工作可以通过石墨烯下方的衬底的调制和液体的界面排序在许多应用中激发创新。
Understanding modulation of liquid molecule slippage along graphene surfaces is crucial for many promising applications of two-dimensional materials, such as in sensors, nanofluidic devices, and biological systems. Here, we use force measurements by atomic force microscopy (AFM) to directly measure hydrodynamic, solvation, and frictional forces along the graphene plane in seven liquids. The results show that the greater slip lengths correlate with the interfacial ordering of the liquid molecules, which suggests that the ordering of the liquid forming multiple layers promotes slip. This phenomenon appears to be more relevant than solely the wetting behavior of graphene or the solid-liquid interaction energy, as traditionally assumed. Furthermore, the slip boundary condition of the liquids along the graphene plane is sensitive to the substrate underneath graphene, indicating that the underlying substrate affects graphene's interaction with the liquid molecules. Because interfacial slip can have prominent consequences on the pressure drop, on electrical and diffusive transport through nanochannels, and on lubrication, this work can inspire innovation in many applications through the modulation of the substrate underneath graphene and of the interfacial ordering of the liquid.