An atmospheric water harvester with fast and energy‐saving water removal and recovery

Moisture removal and water recovery from the air are vital for regulating indoor humidity mitigating scarcity. Most atmospheric harvesters (AWH) focus primarily on increasing moisture capture rate, but it to be economical sustainable, is essential consider energy required recover harvest captured water. Here, a mechanically flexible, biphilic sorption-based AWH made of green, environmentally friendly material presented. It consists hygroscopic chitosan polymer embedded within hydrophobic silica xerogel that can 86.3 g water/g at 97% relative 25°C reaching saturation after 30 days (i.e. 2.88 chitosan/day). Roughly 88% sorbed was recovered by mechanical squeezing (ca. 0.020 MPa) 150 s. Repeated harvesting experiments uniaxial compression tests demonstrate chitosan-silica durable long-term operations, providing fast, reliable, sustainable tool.