POS9-1427
MXene-Integrated Alginate–Salt Hydrogel Beads for Solar-Driven Atmospheric Water Harvesting
Topic
S9. Polymer Technology for Sustainability
When and Where
Sep 30, 2026
08:30 - 09:30
Room 301 (Grand Ballroom)
Session Chairs
Heesuk KIM
Jinhye BAE
Presenter(s)
Tae Hui Park (Chungnam National University)
Co-Author(s)
Abstract
Freshwater scarcity is escalating worldwide, driving urgent demand for sustainable, decentralized water-supply technologies. Sorption-based atmospheric water harvesting (AWH) is attractive because it couples moisture capture with sunlight-driven regeneration. To enable practical, off-grid operation, sorbents must deliver reliable uptake across a wide humidity window with sunlight-only regeneration and acceptable water quality. Here, a bead-type MXene–alginate–LiCl composite hydrogel is developed via Ca2+-mediated ionic cross-linking of sodium alginate, followed by LiCl post-loading, with MXene enabling photothermal-assisted desorption under solar irradiation. The sorbent achieves a maximum moisture uptake of 3.35 g g-1 at 90% RH and 25 °C and remains effective over 30–90% RH. A dome-based condensation device produces ~1.78 g of collected liquid water over 6 h under simulated solar irradiation (1 kW m-2). Outdoor day–night operation further demonstrates practical AWH performance, achieving a nighttime uptake of 1.9 g g-1 after 11 h and producing a liquid water yield equivalent to 105% of the bead mass under natural sunlight for 6 h. The composite also maintains stable performance over 10 sorption–desorption cycles. Notably, elemental analysis of the harvested water (Li+, Ca2+, Mg2+, K+, and Na+) indicates acceptable ionic concentrations relative to WHO guideline values, where available, supporting the practicality of the platform. Overall, this work establishes a scalable bead-based sorbent for sunlight-regenerable AWH under both controlled and outdoor conditions.
