Influence of Asymmetric Geometry on the Ion Transport of Tandem Nanochannels

The unique ion transport properties of ion selectivity, ion current rectification, and concentration polarization at nanoscale have been extensively studied in a single nanochannel. The knowledge of ion transport in tandem nanochannels is still elusive. Here, we report an approach to construct asymmetric tandem nanochannels on an anodic aluminum oxide membrane by repeating anodization and chemical dissolution processes. Study of the ion transport of the asymmetric tandem nanochannels reveals that the tandem structure of the nanochannels significantly affects the ion distribution, which further induces different conductance profiles in the nanochannel at open and close states. It is demonstrated that the differences in the total resistance of the nanochannel between open and close states result in a gradual growth in the ion current rectification ratio of asymmetric tandem nanochannels when increasing the tandem number.

Automated summary

The study showed that the structure of asymmetric tandem nanochannels significantly influences ion distribution, leading to different conductance profiles in the nanochannel at open and close states. Further research is needed in this area to understand the implications of tandem nanochannel structures on ion transport.