The solar powered distillers in use today use a two-dimensional device to absorb heat from sunlight. Scientists at the King Abdullah University of Science and Technology hypothesized that increasing the surface area of the portion of the device that absorbs sunlight might boost the desalination efficiency.
Using interlocking parallelograms found in origami art, scientists have created a 3D structure from cellulose; covered it with a light absorbing nanocarbon composite made from graphene oxide and carbon nanotubes. Their new 3D heat absorber turned out to be 50% more efficient than the 2D devices used in conventional solar powered desalinization equipment.
"Although diverse materials and architectures have been explored to improve solar energy utilization, high efficiency in solar steam generation could be accomplished only with external optical and thermal management," the researchers said. The three-dimensional (3D) origami-based solar steam generator is capable of near full utilization of solar energy.
The researchers say the valleys in the origami-derived structure do a better job of capturing heat from the sun partly because less of the sunlight is reflected away from the heating element. The heat collected flows from the valleys toward the cooler peaks, evaporating water along the way instead of being lost to the surrounding air.