High-Yield Atmospheric Water Harvesting Device with Integrated Heating/Cooling Enabled by Thermally Tailored Hydrogel Sorbent

Sorption-based atmospheric water harvesting (AWH) isregarded asa promising way to produce fresh water in water-stressed areas. However,low water production per unit device mass (WPD) and high energy consumptionrestrict its applications in portable fresh water replenishment. Herewe report a portable high-yield AWH device based on a thermoelectriccell (TEC)-driven integrated heating/cooling thermal design, enabledby a thermally tailored hydrogel sorbent. Heat and cold energies fordesorption and condensation are simultaneously generated by the TEC.Graphene oxide-doped sodium alginate hydrogel with high thermal conductivityis tailored as the sorbent, which tightly adheres to the TEC'shot region and efficiently takes heat away, for fast desorption aswell as temperature control of the TEC. Based on the thermal designof the device and materials, a total WPD of 0.18 L kg(device) (-1) h(-1) is achieved under 80%RH, almost an order of magnitude higher than that of the traditionaldesign with the same energy input.