采用分子动力学(MD)方法,模拟了纳米通道中NaCl溶液的电渗现象.模拟结果表明,与上下两板带同性电荷相比,当纳米通道的上下壁面所带电荷电性相反时,通道中水的浓度分布大致相同,而离子浓度分布,水的速度及通道中的电势分布相差很大.具体表现在:Na+主要聚集在带负电的硅板附近,cl-主要聚集在带正电的硅板附近,通道中部出现电荷倒置现象;在通道下部的区域水的速度为负值,而在上部区域速度为正值;电势在硅板附近呈指数分布,其值在下硅板附近为正,在上硅板附近为负,在模拟区域中段,电势在通道下部区域由正值变为负值,在通道上部区域由负值变为正值.此外,模拟结果还表明:纳米通道中的速度流型随通道壁面电荷分布的改变而改变.
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