Jalali Hossein, Lotfi Erfan, Boya Radha, Neek-Amal Mehdi
Department of Physics, Shahid Rajaee Teacher Training University, 16875-163 Lavizan, Tehran, Iran.
Department of Physics, Sanandaj Branch, Islamic Azad University, Sanandaj, Iran.
J Phys Chem B. 2021 Feb 18;125(6):1604-1610. doi: 10.1021/acs.jpcb.0c09156. Epub 2021 Feb 3.
Ultra-low dielectric constant of nanoconfined water between two flat slabs is a subject of recent experimental and theoretical research. The impact of dissolution of sodium chloride (NaCl) with various concentrations on the dielectric properties of nanoconfined water between graphene layers are investigated using molecular dynamics simulations. We found that, with increasing salt concentration, (i) the out-of-plane dielectric constant increases and (ii) the in-plane dielectric constant decreases non-linearly. Surprisingly, for channels with heights 6.8Å < < 8 Å, we found an abnormal increase in the in-plane dielectric constant versus salt concentration, which can be linked to the formation of 2D-ice-like structure. This study sheds light on the variation of dielectric properties of nanoconfined water between graphene layers in the presence of salt, which is of importance in ion transport and electrochemical energy storage.
两个平板之间纳米限域水的超低介电常数是近期实验和理论研究的主题。使用分子动力学模拟研究了不同浓度氯化钠（NaCl）溶解对石墨烯层间纳米限域水介电性质的影响。我们发现，随着盐浓度的增加，（i）面外介电常数增加，（ii）面内介电常数非线性降低。令人惊讶的是，对于高度在6.8Å < < 8 Å的通道，我们发现面内介电常数相对于盐浓度出现异常增加，这可能与二维类冰结构的形成有关。这项研究揭示了存在盐时石墨烯层间纳米限域水介电性质的变化，这在离子传输和电化学能量存储中具有重要意义。
