Rectifcation of Ion Current Determined by the Nanopore Geometry: Experiments and Modelling
Rectifcation of Ion Current Determined by the Nanopore Geometry: Experiments and Modelling
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由纳米孔几何形状确定的离子电流的整流：实验和建模
DOI：
10.1088/0256-307x/33/10/108501
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发表时间：
2016
影响因子：
3.5
通讯作者：
Li-Yuan Liang
中科院分区：
文献类型：
--
作者：
Da-Ming Zhou;Yun-Sheng Deng;Cui-Feng Ying;Yue-Chuan Zhang;Yan-Xiao Feng;Qi-Meng Huang;Li-Yuan Liang;Li-Yuan Liang
我们提供了一种通过调整施加的电脉冲来精确控制SiNx纳米孔几何形状的方法。通过在浸泡在氯化钾溶液中的SINX膜上施加电流脉冲来产生孔。我们可以用不同的电脉冲产生单个圆锥孔和圆柱孔。基于泊松方程和Nernst-Planck方程的理论模型被用来模拟离子在通道中的输运特性。反过来，我们可以通过拟合实验的电流-电压(I-V)曲线来分析孔的几何形状。对于孔径为0.5~2 nm的锥形孔，其斜率角在−2.5°~−10°之间。此外，通过额外的重复脉冲可以使孔口略有扩大。在正、负偏压下，锥形孔腔变得接近圆柱形通道，导致对称的I-V输运。对这些效应的定性了解将有助于我们按要求制备有用的固体纳米孔。
We provide a way to precisely control the geometry of a SiNx nanopore by adjusting the applied electric pulse. The pore is generated by applying the current pulse across a SiNx membrane, which is immersed in potassium chloride solution. We can generate single conical and cylindrical pores with different electric pulses. A theoretical model based on the Poisson and Nernst—Planck equations is employed to simulate the ion transport properties in the channel. In turn, we can analyze pore geometries by fitting the experimental current-voltage (I–V) curves. For the conical pores with a pore size of 0.5–2nm in diameter, the slope angles are around −2.5° to −10°. Moreover, the pore orifice can be enlarged slightly by additional repeating pulses. The conic pore lumen becomes close to a cylindrical channel, resulting in a symmetry I–V transport under positive and negative biases. A qualitative understanding of these effects will help us to prepare useful solid-nanopores as demanded.