Metal-organic frameworks for solar-driven atmosphere water harvesting

Efficient freshwater production techniques are urgently required to address the global water scarcity problem. In this regard, solar-driven atmospheric water harvesting (AWH) technology, which can capture water vapor from ambient air and release it under sunlight, is a sustainable and feasible strategy to obtain freshwater. Metal-organic frameworks (MOFs) have emerged as promising adsorbents for achieving solar-driven AWH, even in arid regions with relative humidity as low as 10%. During the water desorption process, excellent light absorption and photothermal conversion abilities are much important for fast kinetics and multiple cycles. However, the related photothermal performance of MOFs-based adsorbents has been rarely concerned. Herein, the latest development of MOFs-based adsorbents for efficient solar-driven AWH are reviewed, and corresponding design and modification strategies to improve its water adsorption and photothermal properties are proposed. Besides, water harvesters with different configurations are briefly introduced. Furthermore, an outlook about the key trends of solar-driven AWH is outlined.