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 L_H2O kg_MOF⁻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 L_H2O kg_MOF⁻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 L_H2O kg_MOF⁻¹ d⁻¹ with an energy consumption of 2.96 kW h L_H2O⁻¹, demonstrating the great potential to provide adequate drinking water in real-world scenarios.