Butterfly wings inspire new solar technologies

Co-researcher Kevin Le with a blue Morpho butterfly and a solar cell

Engineers from the Australian National University (ANU) have invented tiny structures inspired by butterfly wings that open the door to new solar cell technologies.

The inspiration comes from the blue Morpho Didius butterfly, which has wings with tiny cone-shaped nanostructures that scatter light to create a striking blue iridescence.

Lead researcher Dr Niraj Lal from the ANU Research School of Engineering said the team made similar structures at the nanoscale and applied the same principles in the butterfly wing phenomenon to finely control the direction of light in experiments.

“There’s a whole bunch of potential new applications using our light-control technique, including next-generation solar cell, architectural and stealth technologies,” Dr Lal said.

He said scientists could greatly improve the efficiency of solar cells with effective light management.

“Techniques to finely control the scattering, reflection and absorption of different colours of light are being used in the next generation of very high-efficiency solar panels,” he said.

“Being able to make light go exactly where you want it to go has proven to be tricky up until now.”

Dr Lal said the aim was to absorb all of the blue, green and ultraviolet colours of sunlight in the perovskite layer of a solar cell, and all of the red, orange and yellow light in the silicon layer – known as a tandem solar cell with double-decker layers.

Researchers at the ANU surpassed silicon efficiency records with such a cell last month.

Dr Lal said the technique could one day be used to make opaque objects transparent to certain colours, and vice versa, as part of new stealth applications.

“We were surprised by how well our tiny cone-shaped structures worked to direct different colours of light where we wanted them to go,” Dr Lal said.

The research paper is published in ACS Photonics, with co-authors Kevin Le, Andrew Thomson, Maureen Brauers, Tom White and Kylie Catchpole.