Aluminophosphate- Based adsorbents for atmospheric water generation

Freshwater resources are being heavily depleted and not replenished at the same high rate, thus, atmospheric water vapor harvesting has earned growing interest. Development of high-performing desiccant or adsorbent materials offering high sorption capacity and selectivity as well as regeneration capability in atmospheric con-ditions is crucial to tackle water scarcity. The required properties to generate potent water sorbents include pore accessibility, high specific surface area and porosity to enable high capture capacity and kinetics, and hydro -thermal resilience to resist cyclic sorption and desorption. Further, polarity, hydrogen bonding, adhesion ability of water molecules to adsorbent surface, and hydrophilic functional groups can boost water adsorption. A highly promising class of water vapor adsorbents is the aluminophosphate molecular sieves (AlPOs), which are microporous zeotype materials. In this review, AlPO-based adsorbents are discussed for water sorption appli-cations and a link is established between performance of materials and their chemical and morphological properties. Synthesis-properties-performance relationships are elucidated in light of synthesis techniques and adsorption behavior, and prospects to enhance AlPOs' water vapor sorption performance toward large-scale water harvesting applications are highlighted.

Automated summary

Freshwater scarcity has led to a growing interest in atmospheric water vapor harvesting. Aluminophosphate molecular sieves show great potential as water vapor adsorbents, with high capture capacity, selectivity, and hydrothermal resilience.