Fig. 1: Conceptual design of packed sorbents with superior water transport kinetics.
a, Schematic of water sorption from air and water desorption from sorbent during water harvesting. b, Schematic of multi-step moisture transport during water sorption process. Water molecules transport from the ambient air to the external surface of sorbents by undergoing surface resistance (Rsurf), which can be tuned by the external airflow rate. Subsequently, the water molecules further diffuse along the connected intrapores by overcoming diffusion resistance (Rsorb), which is mainly affected by the tortuosity factor (τ), the diffusion depth (δsorb) and packed porosity (ε). Finally, the water molecules are captured by the sorption sites of sorbents, mainly determined by the intrinsic reaction resistance (Rreact). c, Morphological evolution from unordered structures to ordered structures of packed sorbents with enhanced heat transfer and mass transport. d, Numerical results of the total mass transport resistances of different packed structures. e, Numerical results of the total heat transfer resistances of different packed structures.
