Water shortages will likely become worse as time wears on, so we need to find a way to collect this precious resource under even the harshest conditions. Harvard University researchers have found a way to harvest water from arid environments by borrowing evolutionary tools from desert beetles, cacti, and carnivorous pitcher plants.
A paper published in Nature this week details the difficulties of creating and controlling dropwise condensation, or what happens when water vapor condenses on dry surfaces, as opposed to surfaces wet from the condensate. It is easy to produce and collect condensation when you have water as a starting ingredient but researchers had to consider what we would do if water is scarce. Organisms who have evolved over time to successfully live in the desert became an obvious choice to study, starting the team down a path of using biomimicry to create a solution.
The Namib desert beetle has an outer shell riddled with bumps, which allows it to trap water vapors present on foggy days. Desert cacti also have their own methods of collecting the water droplets they capture through unique ridges that can pool the condensation. Finally, the slick surface of pitcher plants also played a role in the final material the team produced. Neatly arranged bumps, designed to guide water droplets for collection, are found on the surface of the team’s material, which is coated with a molecularly smooth lubricant to ease the flow of the water.
Joanna Aizenberg, chemical and materials scientist on the team, said, “We envision that this fundamental understanding and rational design strategy can be applied to a wide range of water-harvesting and phase-change heat-transfer applications.” As water-scarce times continue, perhaps this innovative material can help us stay hydrated as we continue to work on other planetary problems – such as climate change.