Universal Reduction in Dielectric Response of Confined Fluids
Universal Reduction in Dielectric Response of Confined Fluids
复制标题
DOI：
10.1021/acsnano.0c03173
复制
发表时间：
2020-10-27
期刊：
影响因子：
17.1
通讯作者：
Aluru, Narayana R.
中科院分区：
文献类型：
--
作者：
Motevaselian, Mohammad H.;Aluru, Narayana R.
介电常数是许多生物和物理化学系统的核心，因为它影响远程静电相互作用。与许多流体性质类似，封闭极大地改变了极性液体的介电响应。许多研究都集中在限制下的水的介电响应的减少。在这里，使用分子动力学模拟，弹性力学理论和多尺度方法，我们研究了平面外（z轴）的介电响应的质子和非质子流体限制在狭缝状石墨烯通道内。我们发现，垂直介电常数的减少是普遍的所有的流体，并表现出朗之万的行为作为通道宽度的函数。我们表明，这种减少是由于有利的面内（x-y平面）偶极偶极静电相互作用的界面流体层。此外，我们观察到一个极端的限制下，令人不安的低介电响应。
Dielectric permittivity is central to many biological and physiochemical systems, as it affects the long-range electrostatic interactions. Similar to many fluid properties, confinement greatly alters the dielectric response of polar liquids. Many studies have focused on the reduction of the dielectric response of water under confinement. Here, using molecular dynamics simulations, statistical-mechanical theories, and multiscale methods, we study the out-of-plane (z-axis) dielectric response of protic and aprotic fluids confined inside slit-like graphene channels. We show that the reduction in perpendicular permittivity is universal for all the fluids and exhibits a Langevin-like behavior as a function of channel width. We show that this reduction is due to the favorable in-plane (x-y plane) dipole dipole electrostatic interactions of the interfacial fluid layer. Furthermore, we observe an anomalously low dielectric response under an extreme confinement.