Rectified ion transport through concentration gradient in homogeneous silica nanochannels
Rectified ion transport through concentration gradient in homogeneous silica nanochannels
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DOI：
10.1021/nl071770c
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发表时间：
2007-10-01
期刊：
影响因子：
10.8
通讯作者：
Guo, L. Jay
中科院分区：
文献类型：
--
作者：
Cheng, Li-Jing;Guo, L. Jay
我们研究了离子整流效应，通过4和20 nm厚的二氧化硅纳米通道放置在两个不同浓度的离子溶液之间。观察到的效果时，只有一侧的通道具有双电层重叠。基于Poisson-Nernst-Planck（PNP）理论和简化模型的计算表明，这一现象是由于纳米通道中的阳离子和阴离子在不同偏压极性下的积累和耗尽所致。该模型还阐明，整流效应的基础上，在纳米流体装置的报告日期是由于不对称的阳离子/阴离子的比例或等效的内置电位的两侧的纳米通道。该研究有利于设计纳流体装置的阿升规模的化学输送。
We investigate the ionic rectifying effect through 4 and 20 nm thick silica nanochannels placed between two ionic solutions of different concentrations. The effect was observed when only a single side of the channel has electric double-layer overlap. The calculation based on Poisson-Nernst-Planck (PNP) theory and a simplified model suggests that the phenomenon result from the accumulation and depletion of both cations and anions in the nanochannels responding to different bias polarities. The model also elucidates that the basis of the rectifying effects in the nanofluidic devices reported to date is due to the asymmetric cation/anion ratios or equivalently built-in potentials on the two sides of the nanochannels. The study benefits the design of nanofluidic devices for attoliter-scale chemical delivery.