Light-Induced Ion Rectification in Zigzag Nanochannels

Ion transport through nanoporous systems has attracted broad interest due to its crucial role in physiological processes in living organisms and artificial bionic devices. In this work, a nanochannel system with a zigzag inner surface was fabricated by using a two-step anodizing technique. The rectification performance of the zigzag channels was observed by I-V measurement in KCl solution. Unlike channels with asymmetric geometry, the mechanism was analyzed based on the "point effect" of charge distribution and "shape effect" of the zigzag channel. The current rectification ratio decreases from nearly 3.0 to 1.0 when the KCl concentration increased from 0.1 mM to 100 mM. The fabrication of different nanopore systems and exploration of novel mechanisms will help to develop biomimetic membranes for practical applications.