Revealing water-biopolymer interactions: Toward advanced water collection from air

The global water scarcity problem is becoming increasingly acute as a result of population growth and environmental changes. Water collection from air is a promising solution and is gaining popularity because it involves the collection of ubiquitous water vapor. The inherent structural properties of biopolymers, including abundant hydrophilic groups, naturally evolved interfaces, and hierarchical structures, provide natural sites for the trapping, transport, and storage of water. Moreover, it is a substantial source of inspiration for scientists, thereby facilitating the design and development of advanced materials for water collection from air. This review commences with a concise overview of the adsorption-desorption mechanism, encompassing the processes of adsorption and uptake in addition to isotherms. The subsequent sections of the paper discuss how biopolymer materials, from the macroscopic to the molecular level, can take advantage of their natural structure to establish interactions with water and realize the applications of water collection from air and point out the advantages of biopolymers for this application in terms of structural design and performance tuning. Finally, the current challenges facing biopolymer resources are summarized. The objective of this review is to establish a novel paradigm for the design of renewable biopolymer-based materials and new green water-efficient recycling technologies.