Nav: Home

Blowin' in the wind -- A source of energy?

March 26, 2018

It may in the future be possible to harvest energy with the aid of leaves fluttering in the wind. Researchers at the Laboratory of Organic Electronics at Linköping University have developed a method and a material that generate an electrical impulse when the light fluctuates from sunshine to shade and vice versa.

"Plants and their photosynthesis systems are continuously subjected to fluctuations between sunshine and shade. We have drawn inspiration from this and developed a combination of materials in which changes in heating between sunshine and shade generate electricity," says Magnus Jonsson, docent and principal investigator for the research group in organic photonics and nano-optics at the Laboratory of Organic Electronics, Linköping University.

The results, which have been verified in both experiments and computer simulations, have been published in Advanced Optical Materials.

Together with researchers from the University of Gothenburg, Magnus Jonsson and his team have previously developed small nanoantennas that absorb sunlight and generate heat. They published an article together in Nano Letters in 2017, describing how the antennas when incorporated into window glass could reduce cold downdraughts and save energy. The antennas, with dimensions in the order of tens of nanometers, react to near infrared light and generate heat.

Mina Shiran Chaharsoughi, PhD student in Magnus Jonsson's group, has now developed the technology further and created a tiny optical generator by combining the small antennas with a pyroelectric film.

"Pyroelectric" means that an electrical voltage develops across the material when it is heated or cooled. The change of temperature causes charges to move and the generation of an electric current in the circuit.

The antennas consist of small metal discs, in this case gold nanodiscs, with a diameter of 160 nm (0.16 micrometres). They are placed on a substrate and coated with a polymeric film to create the pyroelectric properties.

"The nanoantennas can be manufactured across large areas, with billions of the small discs uniformly distributed over the surface. The spacing between discs in our case is approximately 0.3 micrometres. We have used gold and silver, but they can also be manufactured from aluminium or copper," says Magnus Jonsson.

The antennas generate heat that is then converted to electricity with the aid of the polymer. It is first necessary to polarize the polymer film in order to create a dipole across it, with a clear difference between positive and negative charge. The degree of polarisation affects the magnitude of the generated power, while the thickness of the polymer film seems not to have any effect at all.

"We force the polarisation into the material, and it remains polarised for a long time," says Mina Shiran Chaharsoughi.

Mina Shiran Chaharsoughi carried out an experiment in order to demonstrate the effect clearly, holding a twig with leaves in the air flow from a fan. The motion of the leaves created sunshine and shade on the optical generator, which in turn produced small electrical pulses and powered an external circuit.

"The research is at an early stage, but we may in the future be able to use the natural fluctuations between sunshine and shade in trees to harvest energy," says Magnus Jonsson.

Applications that are closer to hand can be found in optics research, such as the detection of light at the nanometre scale. Other applications may be found in optical computing.
-end-
Hybrid Plasmonic and Pyroelectric Harvesting of Light Fluctuations, Mina Shiran Chaharsoughi, Daniel Tordera, Andrea Grimoldi, Isak Engquist, Magnus Berggren, Simone Fabiano, Magnus P. Jonsson, Laboratory of Organic Electronics, Linköping University, Campus Norrköping, Advanced Optical Materials 2018. DOI 10.1002/adom.201701051

Contact: Magnus Jonsson, magnus.jonsson@liu.se +46 11 36 34 03

Linköping University

Related Polymer Articles:

Bundlemers (new polymer units) could transform industries
From tires to clothes to shampoo, many ubiquitous products are made with polymers, large chain-like molecules made of smaller sub-units, called monomers, bonded together.
New synthetic polymer degradable under very mild acidic conditions
A new type of degradable synthetic polymer was prepared by Rh-catalyzed three-component polymerization of a bis(diazocarbonyl) compound, bis(1,3-diketone), and tetrahydrofuran.
New polymer tackles PFAS pollution
toxic polyfluorinated alkyl substances (PFAS) pollution -- commonly used in non-stick and protective coatings, lubricants and aviation fire-fighting foams -- can now be removed from the environment thanks to a new low-cost, safe and environmentally friendly polymer.
New polymer films conduct heat instead of trapping it
MIT engineers have flipped the picture of the standard polymer insulator, by fabricating thin polymer films that conduct heat -- an ability normally associated with metals.
Polymer reversibly glows white when stretched
Polymers that change their appearance in response to mechanical forces can warn of damage developing in a material before the stress causes structural failure.
New materials: Growing polymer pelts
Polymer pelts made of the finest of fibers are suitable for many different applications, from coatings that adhere well and are easy to remove to highly sensitive biological detectors.
A record-long polymer DNA negative
A fragment of a single strand of DNA, built of the nucleobases cytosine and guanine, can be imprinted in a polymer - this has been shown by chemists from Warsaw, Denton and Milan.
Polymer coating cools down buildings
Columbia Engineers have invented a high-performance exterior PDRC polymer coating with nano-to-microscale air voids that acts as a spontaneous air cooler and can be fabricated, dyed, and applied like paint on rooftops, buildings, water tanks, vehicles, even spacecraft -- anything that can be painted.
Keeping things cool with a paint-like polymer
Paving the way to alternatives to high-energy modes of cooling, like air conditioners, researchers now present a polymer that can cool down surfaces by reflecting sunlight and heat back into the sky.
Drexel's polymer pill proves it can deliver
Selecting the right packaging to get precious cargo from point A to point B can be a daunting task.
More Polymer News and Polymer Current Events

Top Science Podcasts

We have hand picked the top science podcasts of 2019.
Now Playing: TED Radio Hour

In & Out Of Love
We think of love as a mysterious, unknowable force. Something that happens to us. But what if we could control it? This hour, TED speakers on whether we can decide to fall in — and out of — love. Guests include writer Mandy Len Catron, biological anthropologist Helen Fisher, musician Dessa, One Love CEO Katie Hood, and psychologist Guy Winch.
Now Playing: Science for the People

#542 Climate Doomsday
Have you heard? Climate change. We did it. And it's bad. It's going to be worse. We are already suffering the effects of it in many ways. How should we TALK about the dangers we are facing, though? Should we get people good and scared? Or give them hope? Or both? Host Bethany Brookshire talks with David Wallace-Wells and Sheril Kirschenbaum to find out. This episode is hosted by Bethany Brookshire, science writer from Science News. Related links: Why Climate Disasters Might Not Boost Public Engagement on Climate Change on The New York Times by Andrew Revkin The other kind...
Now Playing: Radiolab

An Announcement from Radiolab