Environmentally adaptive MOF-based device enables continuous self-optimizing atmospheric water harvesting

Harvesting water vapor from desert, arid environments by metal-organic framework (MOF) based devices to deliver clean liquid water is critically dependent on environment and climate conditions. However, reported devices have yet been developed to adapt in real-time to such conditions during their operation, which severely limits water production efficiency and unnecessarily increases power consumption. Herein, we report and detail a mode of water harvesting operation, termed 'adaptive water harvesting', from which a MOF-based device is proven capable of adapting the adsorption and desorption phases of its water harvesting cycle to weather fluctuations throughout a given day, week, and month such that its water production efficiency is continuously optimized. In performance evaluation experiments in a desert, arid climate (17-32% relative humidity), the adaptive water harvesting device achieves a 169% increase in water production (3.5 L-H2O kg(MOF)(-1) d(-1)) when compared to the best-performing, reported active device (0.7-1.3 L-H2O kg(MOF)(-1) d(-1) at 10-32% relative humidity), a lower power consumption (1.67-5.25 kWh L-H2O(-1)), and saves time by requiring nearly 1.5 cycles less than a counterpart active device. Furthermore, the produced water meets the national drinking standards of a potential technology-adopting country. Atmospheric water harvesting by MOF-based devices is critically dependent on weather conditions. Here, the authors report a MOF-based adaptive water harvesting system capable of adapting its cycles to temperature and relative humidity fluctuations throughout the day, continuously optimizing water production.