Capillary filling speed of water in nanochannels

The capillary filling speed of water in nanochannels with a rectangular cross section and a height on the order of 100 nm has been measured over a length of 1 cm. The measured position of the meniscus as a function of time qualitatively follows the Washburn model. Quantitatively, however, there is a lower than expected filling speed, which we attribute to the electro-viscous effect. For demineralized water in equilibrium with air the elevation of the apparent viscosity amounts up to 24±11% in the smallest channels (53 nm height). When using a 0.1 M NaCl (aq) solution the elevation of the apparent viscosity is significantly reduced.

[1]  P. Fenter,et al.  Molecular-scale density oscillations in water adjacent to a mica surface. , 2001, Physical review letters.

[2]  Miko Elwenspoek,et al.  Institute of Physics Publishing Journal of Micromechanics and Microengineering Wet Anisotropic Etching for Fluidic 1d Nanochannels , 2022 .

[3]  Yamaguchi,et al.  Thermodynamic Quantities of Surface Formation of Aqueous Electrolyte Solutions. , 1999, Journal of colloid and interface science.

[4]  Yu-Chong Tai,et al.  The marching velocity of the capillary meniscus in a microchannel , 2004 .

[5]  S. Woutersen,et al.  Negligible Effect of Ions on the Hydrogen-Bond Structure in Liquid Water , 2003, Science.

[6]  Jan H. J. Fluitman,et al.  Micromachined hydraulic astable multivibrator , 1995, Proceedings IEEE Micro Electro Mechanical Systems. 1995.

[7]  H. Craighead,et al.  Separation of long DNA molecules in a microfabricated entropic trap array. , 2000, Science.

[8]  Uri Raviv,et al.  Fluidity of water confined to subnanometre films , 2001, Nature.

[9]  Takehiko Kitamori,et al.  Nanochannels on a Fused-Silica Microchip and Liquid Properties Investigation by Time-Resolved Fluorescence Measurements , 2002 .

[10]  D. Burgreen,et al.  Electrokinetic Flow in Ultrafine Capillary Slits1 , 1964 .

[11]  Jane E. Curtin,et al.  Nanochannel fabrication for chemical sensors , 1997 .

[12]  E. W. Washburn The Dynamics of Capillary Flow , 1921 .

[13]  Albert van den Berg,et al.  Capillarity Induced Negative Pressure of Water Plugs in Nanochannels , 2003 .

[14]  Manuel G. Velarde,et al.  Dynamic Contact Angles of Water in Ultrathin Capillaries , 2001 .

[15]  Zhang Hai-Lang and,et al.  Viscosity and Density of Water + Sodium Chloride + Potassium Chloride Solutions at 298.15 K , 1996 .

[16]  Zorin,et al.  Surface Tension and Dynamic Contact Angle of Water in Thin Quartz Capillaries. , 2000, Journal of colloid and interface science.

[17]  J. Schultz,et al.  Effect of dynamic contact angle on capillary rise phenomena , 2000 .