Active MOF water harvester with extraordinary productivity enabled by cooling-enhanced sorption

Abstract

Extracting water from the air using a metal-organic framework (MOF) is an emerging solution to mitigate the global water crisis. Reported MOF water harvesters have improved water productivity from 0.1, 1.0 to 3.5 LH2O kgMOF−1 d−1 using different strategies, but still cannot meet practical demands. Herein, we report the design of a MOF water harvester with tunable sorption-desorption behaviors by introducing cooling-assisted adsorption. Triple benefits brought by cooling effects—rapid sorption, enhanced capacity and reduced desorption temperature—deliver extraordinary productivities of 7.75-22.81 LH2O kgMOF−1 d−1 in a diverse range of climates (10-35 °C, 20-80%RH), outperforming the best-performing MOF water harvester. Field tests produced 990.4 mL of clean water continuously throughout the day using a heat pump-integrated harvester in weather with an extremely low RH of 26%, corresponding to a productivity of 9.9 LH2O kgMOF−1 d−1 with an energy consumption of 2.96 kW h LH2O−1, demonstrating the great potential to provide adequate drinking water in real-world scenarios.