Li Mingzhe, Xu Lijiang, Lu Weiyi
Department of Civil and Environmental Engineering, Michigan State University, East Lansing, Michigan 48824, United States.
Langmuir. 2020 May 5;36(17):4682-4688. doi: 10.1021/acs.langmuir.0c00466. Epub 2020 Apr 26.
Understanding liquid motion in nanoenvironment is of fundamental importance in nanofluidics-based systems. While the liquid outflow from hydrophobic nanochannels can significantly affect system performance, its underlying mechanism remains unclear so far. Here, we present an experimental study of the gas-phase effect on liquid outflow behavior from hydrophobic nanochannels in a liquid nanofoam (LN) system. Four LN samples, consisting of same liquid-solid composition but different amounts of the gas phase, are characterized by cyclic quasi-static compression tests. A remarkable difference in the LN system reusability has been observed, indicating that the liquid outflow behavior is highly sensitive to the amount of the gas phase. As the gas amount increases, the degree of liquid outflow from hydrophobic nanochannels is considerably promoted. This promotive effect is because of the suppression of gas outflow and acceleration of bubble nucleation in the nanochannels. These fundamental findings open a new perspective on liquid outflow behavior and can facilitate the design of reusable nanofluidics-based energy absorbers.
了解纳米环境中的液体运动在基于纳米流体的系统中至关重要。虽然疏水性纳米通道中的液体流出会显著影响系统性能，但其潜在机制迄今仍不清楚。在此，我们展示了一项关于气相对液体纳米泡沫（LN）系统中疏水性纳米通道液体流出行为影响的实验研究。通过循环准静态压缩试验对四个由相同液固成分但气相量不同的LN样品进行了表征。观察到LN系统可重复使用性存在显著差异，表明液体流出行为对气相量高度敏感。随着气体量增加，疏水性纳米通道的液体流出程度显著提高。这种促进作用是由于纳米通道中气体流出的抑制和气泡成核的加速。这些基础研究结果为液体流出行为开辟了新视角，并有助于设计可重复使用的基于纳米流体的能量吸收器。
