Hierarchically structured phytoglycogen aerogels for atmospheric water harvesting

Water scarcity in arid regions is a challenge stimulating the need for the development of sustainable methods to harvest water vapor from the atmosphere. In this work, we developed an aerogel with a structural hierarchy for enhanced water capture and release. The aerogel was derived from nature-sourced biodegradable phytoglycogen nanoparticles (PhG NPs) that exhibit strong hydrogen bonding with water molecules. The crosslinking of acryloyl-modified PhG NPs produced microgel particles that were used as building blocks for a macroscopic hydrogel. The removal of water from this hydrogel yielded an aerogel with three characteristic pore dimensions, that is, several nanometer-, tens of nanometer-, and micrometer-size pores. The aerogel showed enhanced water-harvesting capacity and sorption kinetics. This hierarchically structured aerogel shows promise as an eco-friendly material for atmospheric water harvesting and offers a sustainable alternative to traditional sorbents.