Alanis Kristen, Siwy Zuzanna S, Baker Lane A
Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States of America.
Department of Physics and Astronomy, University of California, Irvine, California 92697, United States of America.
J Electrochem Soc. 2023;170(6). doi: 10.1149/1945-7111/acdd29. Epub 2023 Jun 21.
Single nanopores in silicon nitride membranes are asymmetrically modified with Nafion and investigated with scanning ion conductance microscopy, where Nafion alters local ion concentrations at the nanopore. Effects of applied transmembrane potentials on local ion concentrations are examined, with the Nafion film providing a reservoir of cations in close proximity to the nanopore. Fluidic diodes based on ion concentration polarization are observed in the current-voltage response of the nanopore and in approach curves of SICM nanopipette in the vicinity of the nanopore. Experimental results are supported with finite element method simulations that detail ion depletion and enrichment of the nanopore/Nafion/nanopipette environment.
氮化硅膜中的单个纳米孔用全氟磺酸离子交换膜进行不对称修饰，并通过扫描离子电导显微镜进行研究，其中全氟磺酸离子交换膜改变了纳米孔处的局部离子浓度。研究了施加的跨膜电位对局部离子浓度的影响，全氟磺酸离子交换膜在纳米孔附近提供了一个阳离子库。基于离子浓度极化的流体二极管在纳米孔的电流 - 电压响应以及纳米孔附近扫描离子电导显微镜纳米吸管的接近曲线中被观察到。有限元方法模拟支持了实验结果，该模拟详细说明了纳米孔/全氟磺酸离子交换膜/纳米吸管环境中的离子耗尽和富集情况。
