Hydrophilicity and the viscosity of interfacial water
Hydrophilicity and the viscosity of interfacial water
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DOI：
10.1021/la062299q
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发表时间：
2007-05-08
期刊：
影响因子：
3.9
通讯作者：
Zhu, X-Y.
中科院分区：
文献类型：
--
作者：
Goertz, Matthew P.;Houston, J. E.;Zhu, X-Y.
我们测量了纳米厚的水膜在无定形二氧化硅表面的界面上的粘度。我们从三个不同的测量中获得粘度值：在环境条件下，在氧化端W尖和二氧化硅表面之间形成的水半月板中的摩擦力；在水下对这些界面进行了类似的测量；以及两个表面在水中以不同速度接近时的排斥力。在这三种情况下，我们获得的有效粘度都比纳米级界面分离的散装水的有效粘度大10(6)倍。当我们用-H或-CH3终止表面的亲水性时，不会观察到这种增强的粘度。根据最近其他界面的结果，我们得出结论，形成粘性界面的判据是界面对的亲水性程度。
We measure the viscosity of nanometer-thick water films at the interface with an amorphous silica surface. We obtain viscosity values from three different measurements: friction force in a water meniscus formed between an oxide-terminated W tip and the silica surface under ambient conditions; similar measurements for these interfaces under water; and the repulsive "drainage" force as the two surfaces approach at various speeds in water. In all three cases, we obtain effective viscosities that are similar to 10(6) times greater than that of bulk water for nanometer-scale interfacial separations. This enhanced viscosity is not observed when we degrade the hydrophilicity of the surface by terminating it with -H or -CH3. In view of recent results from other interfaces, we conclude that the criterion for the formation of a viscous interphase is the degree of hydrophilicity of the interfacial pair.