Researchers at the Massachusetts Institute of Technology created the thinnest, lightest solar cells, demonstrating that powering electronic devices with solar cells this small is possible. The researchers, whose study has been published in the journal Organic Electronics, claim the solar cells are so lightweight that they could be placed on any material without anyone noticing it.
The researchers used parylene as both the substrate to support the cells and the overcoating to protect them from the environment. Parylene is a common polymer that is used as plastic coating for circuit boards and biomedical devices. For its light-absorbing layer, they used an organic material called DBP.
To test its thinness and lightweight capability, the researchers placed the cells on top of a soap of bubble. They found that even if the cells were placed on the parylene, they still converted the sunlight just as efficiently as when placed on a glass carrier. Overall, the cells, including the substrate and overcoating, measured about one-fiftieth of the thickness of a human hair.
The researchers note that any material can be used for the carrier. Additionally, the power these cells produced were not necessarily practical but still, its power-to-weight ratio is the highest observed, a factor that is crucial when powering weight-sensitive technology like spacecraft or helium balloons.
“It could be so light that you don’t even know it’s there, on your shirt or on your notebook,” says MIT professor Vladimir Bulovic. “These cells could simply be an add-on to existing structures.”
The research team admits that this study just shows the concept. Developing this into a product that can be marketed would take a lot of effort and time. Nevertheless, they have proved the capability of solar cells at this size to produce power, innovating the ways to harness solar power.