Solar driven thermal responsive polyionic liquid/PDDA semi-IPN hydrogel for near-room temperature membrane-free osmotic desalination

We report a mushroom-shaped thermally responsive polyionic liquid (TPIL)/PDDA hydrogel (PNCl) with a semi-interpenetrating (semi-IPN) structure containing highly charged chloride anions. It was fabricated to explore the comprehensive capabilities of long-term availability and membrane-free osmotic desalination without infrastructure restriction and intensive energy consumption. A record high salt rejection is above 93% for membrane-free desalination from artificial seawater (0.6 M NaCl).