A binary salt composite adsorbent material for solar-driven sorption-based atmospheric water harvesting

Solar-driven sorption-based atmospheric water harvesting (SSAWH) technology stands as a promising avenue for sourcing freshwater in arid and remote regions. For real-world large-scale applications, the effective water absorption capacity , broad humidity absorption range, and rapid desorption properties of adsorbent materials have been the main goals of the research area. In this context, we have developed a binary salt composite adsorbent material (PAMg-Li) for solar-driven water harvesting by integrating binary hygroscopic salts MgSO 4 particles and LiCl particles, activated carbon fiber (ACF), and polyvinyl alcohol (PVA). The inherent porous structure and interconnected channels at micro and nano scales of PAMg-Li facilitate water absorption, and obtained satisfactory water absorption rate even at 30% relative humidity (RH). It has been shown to be able to achieve a high water storage capacity and realize water desorption under natural light. A home-made device based on PAMg-Li obtained a water evaporation rate of 0.084 kg/(m 2 ·h) under solar radiation intensities ranging from 200 to 850 W/m 2 . The PAMg-Li material developed in this work can be a candidate for a more practical and effective choice for SSAWH.