Directing droplets using microstructured surfaces

被引:217
作者
Shastry, Ashutosh [1 ]
Case, Marianne J. [1 ]
Bohringer, Karl F. [1 ]
机构
[1] Univ Washington, Dept Elect Engn, Seattle, WA 98195 USA
关键词
D O I
10.1021/la0601657
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Systematic variation of microscale structures has been employed to create a rough superhydrophobic surface with a contact angle gradient. Droplets are propelled down these gradients, overcoming contact angle hysteresis using energy supplied by mechanical vibration. The rough hydrophobic surfaces have been designed to maintain air traps beneath the droplet by stabilizing its Fakir state. Dimensions and spacing of the microfabricated pillars in silicon control the solid-liquid contact area and are varied to create a gradient in the apparent contact angle. This work introduces the solid-liquid contact area fraction as a new control variable in any scheme of manipulating droplets, presenting theory, fabricated structures, and experimental results that validate the approach.
引用
收藏
页码:6161 / 6167
页数:7
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