Hydration shell energy barrier differences of sub-nanometer carbon pores enable ion sieving and selective ion removal

Subnanometer pores of carbon discriminate against ions based on their size. Capitalizing on such nuanced differences enables ion separation via charge/discharge cycling during ion electrosorption. Different ion uptake capacities in aqueous media with multiple, competing ions are also of high importance to understand capacitive deionization of surface water or industrial process water. In our experiments, we observed divalent cations sieving in...