Diatoms, a group of phytoplankton, called the “jewels of the sea” because of their glassy silica shells that warp light. Now, Yale researchers hope to harness that property to boost solar technology.
Andre Taylor, associate professor of chemical & environmental engineering, said, fossilized diatoms used to solve a design problem that has long plagued the development of organic solar cells.
The abundant diatoms found in all kinds of water and even in the bark of trees. The diatoms possess a skeleton made of nanostructured silica or glass. They help trap and scatter light for the algae to photosynthesize.
These small creatures could prove particularly valuable for the design of solar technologies known as organic photovoltaic. The challenge of designing these devices is they require very thin active layers, which limits their efficiency in converting light to electricity. The ways to correct this include embedding nanostructures that trap and scatter light to enhance the absorption levels. These approaches are too costly for large-scale production.
Diatoms optimized light absorption through billions of years of adaptive evolution. The most common type of phytoplankton found in nature, they’re cheap and can find almost anywhere. The research team dispersed diatoms throughout the active layer of the solar cell. By doing, they reduced the amount of the material needed for the active layer, but maintained the same levels of electrical output.
Although the diatoms initially too large for the active layer, they could fix that with a simple grinding process. Researchers said, it didn’t interrupt existing processing steps, so it doesn’t add any complexities or challenges, and can an easy addition to existing commercialized organic solar cells.
Researchers use different species of diatoms and tailor it to the right size, and also use some of the better donor-acceptor polymers for a higher performance.
More information: [Organic Electronics]