Researchers have created a new type of crystalline material that can naturally collect water from fog without requiring any energy. This innovative device, called Janus crystals, draws inspiration from desert plants and animals that thrive in dry environments.
A collaborative team from Jilin University, NYU Abu Dhabi’s Smart Materials Lab, and the Center for Smart Engineering Materials, guided by Professor of Chemistry Pance Naumov, has developed a new crystalline material that can harvest water from fog without any energy input.
The design behind these cutting-edge smart crystals, known as Janus crystals, is modeled after desert organisms that have adapted to survive in harsh climates. For instance, desert beetles and lizards have evolved to possess surface textures that feature both water-attracting (hydrophilic) and water-repelling (hydrophobic) sections, which help them capture moisture from the air. The hydrophilic areas draw in water, while the hydrophobic regions facilitate the movement of droplets towards a collection area.
The researchers detailed their findings in a study titled “Efficient Aerial Water Harvesting with Self-Sensing Dynamic Janus Crystals,” recently published in the Journal of the American Chemical Society. They selected three organic compounds with diverse chemical properties to grow flexible organic crystals. Afterward, they evaluated how each of these compounds responded to airborne moisture, leading to the development of the new water-gathering Janus crystals, which feature both hydrophilic and hydrophobic surfaces designed for water accumulation and transfer. These Janus crystals are capable of collecting moisture from the air with impressive efficiency. Their slim and light-translucent shapes allow scientists to observe the collection and condensation of fog droplets in real time using light.
Desalination is a common technique used to create drinking water from saltwater, but it requires a significant amount of energy to remove the dissolved salt. In contrast, Janus crystals utilize the natural condensation of airborne moisture or fog, a spontaneous process that can occur without any energy input, potentially providing a continuous supply of clean water. Unlike previous porous organic crystals, the Janus crystals integrate both water-collection and delivery features on their surfaces, enhancing the efficiency of the water harvesting process under ambient conditions.
“Our atmosphere holds a vast amount of untapped fresh water, but we urgently need materials capable of effectively collecting and converting this humidity into drinking water,” expressed Naumov. “The crystals developed by our team not only leverage the flexibility and light-transmitting properties of organic materials but also set the stage for creating active, self-sensing, and efficient harvesters. When scaled, these could significantly aid in addressing water scarcity on a larger scale.
