離子液體是由有機陽離子和無機/有機陰離子組成的鹽類，一般在室溫或接近室溫下呈現液態，具有熱穩定性高、不可燃性、反應溫度範圍廣等諸多特殊性質，其中低揮發性和可回收再利用特性，使離子液體被視為環境友善的綠色溶劑(green solvent)。除此之外，人們可以根據對離子液體的需求改變陰離子和陽離子之組成，因此離子液體也被認為是設計者溶劑(designer solvent)。這些特質讓離子液體無論是在學術方面或是工業界的研究都十分活躍、深入，並且涉及的領域也從生物、化學與化工拓展到光電、環境等，在未來具有十足的發展性。外加電場下的離子液體變形及其力學行為是電流體動力學領域的重點研究，本文採用分子動力學模擬方法，設計三種簡易分子結構的離子液體，並應用分子動力學軟體LAMMPS建立模型，研究不同結構的奈米離子液體，在外加直流和交流電場作用下，液體形狀及物理性質所產生的改變。並且研究在電場作用下，離子液體在單一固體基材(substrate)上的變形行為，更進一步改變固體基材的條件，包括基材原子數量、表面粗糙度和表面形狀，探討不同情況的固體基材對離子液體變形行為的影響。

Ionic liquids are salt composed of an organic cation and an inorganic/organic anion. They have many unique properties, such as high thermal stability, incombustibility and wide range of reaction temperature. In addition, people can combinate different anions and cations according to the demand for ionic liquids. Therefore, they are also considered as designer solvents. The deformation and mechanical behavior of ionic liquid under the electric field are key issues of research on electrohydrodynamics. In this paper, three simple molecular structures of ionic liquids are designed and the simulation models are established by molecular dynamics. One of the purposes of this study is to investigate the deformation of different ionic liquids under DC and AC electric field. The other is to study the deformation of ionic droplet on the solid substrate under the external electric field. Moreover, we change the atoms of substrate, surface roughness and surface geometry of substrates to investigate the effect of the substrates on the ionic liquids.

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