Biomimetic Ion Channels with Subnanometer Sizes for Ion Sieving: A Mini-review

The remarkable ion selectivity of biological systems has inspired the development of artificial ion channels with Ångström-scale precision, expanding their potential applications in ion separation, energy conversion, and water purification. This mini-review systematically examines fundamental ion-sieving mechanisms operating at the subnanoscale, highlighting advanced fabrication strategies involving synthetic ion channels on lipid bilayers and solid-state ion channels. We further explore membrane material innovations spanning zero-dimensional nanopores to three-dimensional crystalline frameworks, emphasizing structure-function relationships in channel design. The discussion concludes with critical perspectives on scalability challenges and future research directions, outlining pathways toward next-generation sustainable ion sieving technologies.