Diatoms, a kind of algae that reproduces prodigiously, have been called “the jewels of the sea” for their ability to manipulate light. Now, researchers hope to harness that property to boost solar technology.
In the lab of Andre Taylor, associate professor of chemical & environmental engineering, fossilized diatoms are being used to solve a design problem that has long plagued the development of organic solar cells. The results of their work are published in Organic Electronics.
The abundant diatoms are found in all kinds of water and even in the bark of trees, and possess a skeleton made of nanostructured silica or glass. “It’s really amazing that these things exist in nature,” said Lyndsey McMillon-Brown, a Ph.D. student in Taylor’s lab and lead author of the study. “They help trap and scatter light for the algae to photosynthesize, so we’re able to use something directly from nature and put it in a solar cell.”
These small creatures could prove to be particularly valuable for the design of solar technologies known as organic photovoltaics – a lower-cost option to conventional solar technologies. One challenge of designing these devices, though, is that they require very thin active layers (100 to 300 nanometers), which limits their efficiency in converting light to electricity. Ways to correct this include embedding nanostructures that trap and scatter light to enhance the absorption levels. These approaches, though, are too costly for large-scale production.