Water desalination across multilayer graphitic carbon nitride membrane: Insights from non-equilibrium molecular dynamics simulations
Water desalination across multilayer graphitic carbon nitride membrane: Insights from non-equilibrium molecular dynamics simulations
复制标题
多层石墨氮化碳膜的海水淡化：非平衡分子动力学模拟的见解
DOI：
10.1016/j.carbon.2018.08.043
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发表时间：
2018-12-01
期刊：
影响因子：
10.9
通讯作者：
Li, Jinyu
中科院分区：
文献类型：
--
作者：
Liu, Yichang;Xie, Daoqing;Li, Jinyu
石墨氮化碳（g-C3N4）是一种新型的二维氮掺杂碳材料，在许多领域都有广泛的应用。近年来，g-C3N4表现出优异的分离能力。在这项工作中，研究了水和离子在不同孔径的纳米多孔g-C(3)N(4)膜上的渗透机理。模拟得到的水导率与前人的实验数据吻合较好。由于纳米尺度的限制，我们在最窄的纳米通道内观察到堆叠的水团簇结构。相似的结构随着纳米通道尺寸的增加而变得模糊。对于海水淡化目的，我们发现具有所需开口的纳米多孔g-C3N4膜可以完全排除钙离子和氯离子，而以可接受的拒除率（超过70%）筛除单价阳离子。这项工作提供了水和离子通过纳米多孔g-C3N4传输的分子机制，这有力地支持了这种新型材料是开发选择性海水淡化膜的有希望的候选材料。(C) 2018 Elsevier Ltd.版权所有。
Graphitic carbon nitride (g-C3N4) is a novel two-dimensional, nitrogen-doped carbon material with various applications in many fields. Recently, g-C3N4 has exhibited excellent ability in separations. In this work, mechanisms of water and ion permeation across nanoporous g-C(3)N(4)membranes with different pore diameters were studied using non-equilibrium molecular dynamics simulations. The water conduction rates derived from our simulations are in good agreement with previous experimental data. Due to the nanoscale confinement, we observe a stacked water cluster structure within the narrowest nanochannel. Similar structures are obscure as the increase of the nanochannel sizes. For desalination purposes, we find that the nanoporous g-C3N4 membrane with the desired opening may completely reject calcium and chloride ions, whereas sieve out monovalent cations with acceptable rejection rates (over 70%). This work provides molecular insight into the mechanism of water and ion transport through nanoporous g-C3N4 , which strongly supports that this novel material is a promising candidate for developing selective membrane for water desalination. (C) 2018 Elsevier Ltd. All rights reserved.