Electrochemical Probing of Steric, Electrostatic and Hydrophobic Interactions of Large Cations in Polymers of Intrinsic Microporosity

Porous membranes have been used for many applications, including separations in biotechnology, the food industry, water purification, and even energy storage devices. The benefit of polymers of intrinsic microporosity (PIMs) is their consistently sized nanopore channels. Inherent functionalities of the PIM structure not only create these channels but are also available for further modifications that can change the interactions of ions and molecules inside of the pore. Here we design solid state nanopores on which are drop-casted two different PIMs, functionalized with either a cyano group or a carboxylic acid. Ionic transport through the membranes is investigated based on pore size and charge-charge interactions, as well as steric and hydrophobic interactions. Achieving specific ion selectivity with easily processable porous membranes opens new avenues for water purification strategies and energy storage.

Automated summary

This study investigates the application of solid state nanopores based on PIMs in ion transport and interactions. By controlling the pore structure and selecting functional groups, nanopore channels with consistent sizes can be achieved, and the interactions between ions and molecules inside the pores can be modified, opening up new avenues for water purification and energy storage.