
Colour-changing artificial ‘chameleon skin’ powered by nanomachines via University of Cambridge
Researchers have developed artificial ‘chameleon skin’ that changes colour when exposed to light and could be used in applications such as active camouflage and large-scale dynamic displays.
The material, developed by researchers from the University of Cambridge, is made of tiny particles of gold coated in a polymer shell, and then squeezed into microdroplets of water in oil. When exposed to heat or light, the particles stick together, changing the colour of the material. The results are reported in the journal Advanced Optical Materials.
In nature, animals such as chameleons and cuttlefish are able to change colour thanks to chromatophores: skin cells with contractile fibres that move pigments around. The pigments are spread out to show their colour, or squeezed together to make the cell clear.
The artificial chromatophores developed by the Cambridge researchers are built on the same principle, but instead of contractile fibres, their colour-changing abilities rely on light-powered nano-mechanisms, and the ‘cells’ are microscopic drops of water.
When the material is heated above 32C, the nanoparticles store large amounts of elastic energy in a fraction of a second, as the polymer coatings expel all the water and collapse. This has the effect of forcing the nanoparticles to bind together into tight clusters. When the material is cooled, the polymers take on water and expand, and the gold nanoparticles are strongly and quickly pushed apart, like a spring.
“Loading the nanoparticles into the microdroplets allows us to control the shape and size of the clusters, giving us dramatic colour changes,” said Dr Andrew Salmon from Cambridge’s Cavendish Laboratory, the study’s co-first author.
The geometry of the nanoparticles when they bind into clusters determines which colour they appear as: when the nanoparticles are spread apart they are red and when they cluster together they are dark blue. However, the droplets of water also compress the particle clusters, causing them to shadow each other and make the clustered state nearly transparent.
At the moment, the material developed by the Cambridge researchers is in a single layer, so is only able to change to a single colour. However, different nanoparticle materials and shapes could be used in extra layers to make a fully dynamic material, like real chameleon skin.
The researchers also observed that the artificial cells can ‘swim’ in simple ways, similar to the algae Volvox. Shining a light on one edge of the droplets causes the surface to peel towards the light, pushing it forward. Under stronger illumination, high pressure bubbles briefly form to push the droplets along a surface.
“This work is a big advance in using nanoscale technology to do biomimicry,” said co-author Sean Cormier. “We’re now working to replicate this on roll-to-roll films so that we can make metres of colour changing sheets. Using structured light we also plan to use the light-triggered swimming to ‘herd’ droplets. It will be really exciting to see what collective behaviours are generated.”
Learn more: Colour-changing artificial ‘chameleon skin’ powered by nanomachines
The Latest on: Chameleon skin
via Google News
The Latest on: Chameleon skin
- Bacteria “Croak” in the Presence of Toadlet Peptideon January 15, 2021 at 5:00 am
Antibacterial peptide secreted on the skin of the Australian toadlet, may lead to the development of drugs to fight bacterial infections.
- 5 Ways To Use Leftover Soup Without Getting (Ahem) Soup-er Sick of Iton January 14, 2021 at 6:13 am
Michele Di Pietro is a culinary consultant and the author of SOUPified: Soups Inspired by Your Favorite Dishes.
- Fans Slam Madonna For Shocking New Face: ‘What Just Happened?’on January 7, 2021 at 4:00 pm
Madonna has always been a chameleon when it comes to her flamboyant ... Some online haters brought up the fact that her nose was blurred, and her skin smoothed out in the shocking photo.
- Remembering Stella Tennant: the photographs that made her a fashion staron January 7, 2021 at 4:59 am
From bikinis on the Chanel catwalk to still being in demand at 49, Tennant's career stretched almost three decades ...
- Spider-Man: 10 Times Peter Parker Held A Grudgeon January 6, 2021 at 2:50 pm
While there have been a number of enemies who have gotten under Spider-Man's skin, Peter Parker has made a few enemies himself over the years.
- The best animated Decals in Rocket Leagueon January 5, 2021 at 12:59 pm
Customize your car with these awesome Decals. The post The best animated Decals in Rocket League appeared first on Gamepur.
- Jerry Dixon Headshoton December 26, 2020 at 4:00 pm
Broadway and Off-B'way Original Cast: Once on This Island (Daniel), Five Guys Named Moe (Nomax), Bright Lights, Big City (Tad), The Bubbly Black Girl Sheds Her Chameleon Skin (Lucas), tick ...
- Wake Up With BWW 12/16: Broadway-Bound HOUDINI Musical in the Works, and More!on December 16, 2020 at 2:19 am
Among her off-Broadway credits are INKED BABY, DESSA ROSE, THE BUBBLY BLACK GIRL SHEDS HER CHAMELEON SKIN, THE VAGINA MONOLOGUES, OUT OF THIS WORLD and more.
- Robot Chameleon Teaches Little Girl About Camouflageon November 30, 2020 at 4:01 pm
A few days ago, they stumbled upon the chameleon, and when he tried to explain ... She’s starting to learn how some chameleons can change their skin color in order to camouflage — and she ...
- Chameleons inspire 'smart skin' that changes color in sunon September 12, 2019 at 10:51 am
A chameleon can alter the color of its skin so it either blends into the background to hide or stands out to defend its territory and attract a mate. The chameleon makes this trick look easy, using ...
via Bing News