Device design and optimization of sorption-based atmospheric water harvesters

Abstract

Atmospheric water harvesting (AWH) is a promising approach to providing fresh water to areas without access to large bodies of freshwater and mitigating imbalanced water distribution. Besides material innovations, researchers have explored different design strategies for these AWH devices, which can be divided into monocyclic and multicyclic types. Monocyclic water harvesters can be further categorized into those using upward vapor escape, for which research efforts have focused on reducing top cover heating and increasing sorption capacity, and those using downward vapor escape, for which research efforts have focused on heat recycling and cooling strategies to enhance condensation efficiency. Notably, some of these devices utilize radiative cooling and require zero external energy input. For multicyclic water harvesters, efforts have focused on optimizing the sorbents’ water uptake kinetics and device design geometry to guarantee continuous water harvesting.