A research team comprising scientists from Jilin University, NYU Abu Dhabi’s Smart Materials Lab, and the Center for Smart Engineering Materials, under the leadership of Professor Pance Naumov, has created an innovative crystalline material capable of harvesting water from fog without requiring any energy input. The findings are published in the Journal of the American Chemical Society.
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This unique material, referred to as Janus crystals, draws inspiration from desert plants and animals adapted to thrive in arid environments. For instance, certain desert beetles and lizards possess surfaces with both hydrophilic and hydrophobic properties, enabling them to efficiently collect moisture from the air. The hydrophilic areas attract water, while the hydrophobic regions facilitate the movement and accumulation of droplets.
The researchers selected three chemically adaptable organic compounds to grow elastic organic crystals and investigated how these materials interacted with airborne water. This work led to the development of Janus crystals, which feature hydrophilic and hydrophobic zones on their surfaces. These properties allow the crystals to effectively capture water and transport it to a receptacle for collection.
The Janus crystals demonstrated the highest water collection efficiency observed to date from humid air. Their slender, translucent structures also enabled real-time observation of fog droplet condensation and collection using light.
While desalination is a commonly used technique to produce drinkable water, it requires significant energy to separate salt from seawater. In contrast, Janus crystals utilize spontaneous condensation of aerial humidity or fog under ambient conditions, removing the requirement for energy input and potentially providing an unlimited source of clean water. Unlike earlier porous organic crystals, Janus crystals integrate both water-collection and delivery functions on their surfaces, resulting in a highly efficient process that maximizes water harvesting in natural conditions.
The earth’s atmosphere contains an abundance of untapped fresh water, but we desperately need materials that can efficiently capture and collect this humidity and condense it into potable water. The crystals developed by our team not only capitalize on the mechanical compliance and optical transparency of organic crystals, but also pave the way for the design of active, self-sensing, and efficient surface-active harvesters which, when used at a larger scale, can help us combat water scarcity at a societal level.
Pance Naumov, Professor, Smart Materials Lab, New York University Abu Dhabi
Journal Reference:
Lan, L., et al. (2024) Efficient Aerial Water Harvesting with Self-Sensing Dynamic Janus Crystals. Journal of the American Chemical Society. doi.org/10.1021/jacs.4c11689.