A team of researchers at the University of Sydney have created a new low-cost material inspired by a beetle found in the Namib Desert. The discovery could help capture water right out of thin air.
The chemical researchers used micro-structures on the elytra (hardened wing case) of the Physosterna cribripes desert beetle to inspire the new material. These small structures or bumps attract water while the surrounding areas are water-repellent.
The resultant coating technology could then be used for atmospheric water capture in the event of drought, emergency situations, or in locales isolated from the main water grid.
Associate Professor Chiara Neto from the University’s School of Chemistry and Australian Institute for Nanoscale Science and Technology (AINST) was co-author of the paper which was published in the American Chemical Society journal Applied Materials & Interfaces. She is also leader of the AINST domain in molecular nanoscience.
“We have been working in the area of biomimetic material for a few years now, and the idea of biomimetic water capture is particularly interesting for its potential to benefit the sustainable use of resources,” Neto said.
Biomimetic simply means a synthetic process, substance or system which copies something found in nature.
Neto said that by refining the approach for forming these microscopic patterns, the material could be put to large-scale use. Additionally, researchers found the optimal size and distribution of the micro-patterns to efficiently form and collect the water drops without any additional energy input.
“Some of the patterns that we have designed are able to collect substantially more water (57% more in volume) than flat plastic sheets under harsh circumstances, for example under low humidity or with no active cooling of the surface. In practice, what this means is that exposing our micro-patterned surfaces to the night sky will result in more dew events than on a flat plastic sheet,” Neto said.
“In an emergency or drought situation, this difference could literally mean the difference between life and death.”
By passively cooling the material under the night sky, dew formation was encouraged. This means the new micro-patterned material would have a larger number of dewy nights than a flat hydrophobic surface (i.e one that repels water).