A comprehensive review of approaches, systems, and materials used in adsorption-based atmospheric water harvesting.

Atmospheric water harvesting (AWH) is one of the most efficient, sustainable, cost-effective, and promising techniques for addressing world's water scarcity. Over 4.3 billion people around the world struggle to access clean, abundant, and safe drinking water. Additionally, >3.3 million people die each year due to drinking poor quality water. Meanwhile, our atmosphere contains approximately 13,000 trillion liters of water in the form of vapor. Therefore, AWH offers a viable solution to meet the demand for drinking water, even in arid or high humidity regions. AWH can be achieved through methods such as fog harvesting, dew harvesting and sorption-based atmospheric water harvesting (SBAWH). The main aim of this manuscript is to explore the potential of Sorption-Based Atmospheric Water Harvesting (SBAWH) as a solution to the global water scarcity crisis. The study focuses on evaluating the adsorption capacities and performance of various sorbent materials, systems, and devices used in SBAWH. Notably, materials such as silica gel, zeolite, hygroscopic salts, and metal-organic frameworks (MOFs) are highlighted, with MOFs and their composites being recognized as some of the most efficient options for atmospheric water harvesting. This review emphasizes the critical role of AWH techniques in addressing the pressing issue of global water shortages.