Engineering ion selectivity in polymer membranes*

Selective separation of monovalent cationic species from complex mixtures is an industrially relevant procedure necessary for the recovery of many commodity materials, such as lithium from salt brines. Unfortunately, most conventional membranes lack selectivity between monovalent ions, rendering their use in such applications infeasible. One approach to overcoming selectivity limitations is to incorporate ligands into polymer matrices which specifically interact with target cations in an aqueous environment. In this talk, I will discuss a few recent topics from our work on using atomistic and coarse-grained simulations to uncover the physics of solubility and diffusivity selectivities in polymer membranes. Our findings provide critical molecular-level insight into the interplay between membrane chemistry and monovalent ion selectivity, aiding in the rational design of selective membranes for resource recovery.