Novel ionic transporting phenomena emerge as nanostructures approach the molecular scale. At the sub-2nm scale, widely used continuum equations, such as the Nernst–Planck equation, break down. Here, we extend the Nernst–Planck equation by adding a partial dehydration effect. Our model agrees with the reported ion fluxes through graphene oxide laminates with sub-2nm interlayer spacing, outperforming previous models. We also predict that the selectivity sequences of alkali metal ions depend on the geometries of the nanostructures. Our model opens a new avenue for the investigation of the underlying mechanisms in nanofluidics at the sub-2nm scale.

中文翻译：

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包含部分脱水效应的扩展的Nernst–Planck方程

随着纳米结构接近分子规模，出现了新型的离子迁移现象。在2nm以下的尺度上，被广泛使用的连续体方程式（例如Nernst-Planck方程式）崩溃了。在这里，我们通过添加部分脱水效应来扩展Nernst-Planck方程。我们的模型与报道的通过2纳米以下层间间距的氧化石墨烯层压板的离子通量相符，优于以前的模型。我们还预测碱金属离子的选择性序列取决于纳米结构的几何形状。我们的模型为研究亚2纳米规模的纳米流体的潜在机理开辟了一条新途径。