At the Massachusetts Institute of Technology (MIT) they imagined a solar cell so thin, flexible and light that can fit any surface, from a t-shirt to a smart phone screen, or even a piece of paper or an air balloon; so light it can stand on a soap bubble.
A dream that MIT researchers have already achieved, thanks to the support of the Eni-MIT Solar Frontiers Center, and the National Science Foundation, producing lighter and thinner solar cells. Although a commercial production may take years, they developed a new approach to create solar cells that could help provide power to a next generation of electronic devices, especially portable.
The one-of-a-kind procedure is described in a study by Vladimir Bulovic, Annie Wang and Joel Jean. Bulovic explains that "the key to the new approach is to obtain the solar cell, the substrate that supports and a protective overcoating to protect it from the environment with a single process. The substrate is made in one location and must not be handled, cleaned, or removed from the vacuum during the manufacturing process, while minimizing exposure to dust or other contaminants that may degrade the performance of the cell. The innovative step is the realization that you can grow the substrate at the same time while growing the device".
The team has already created the thinnest and lightest full solar cells ever made and to prove it they placed one cell on top of a soap bubble. The researchers acknowledge that this cell might be too thin to be used: “If you breathe too hard, you might blow it away” says Joel Jean. Anyway this super-thin film can be easily deposited on commercial equipment, such as a smartphone. The final result are ultra-thin, flexible solar cells that are just one-fiftieth of the thickness of a human hair and one-thousandth of the thickness of equivalent cells on glass substrates and yet they are able to convert sunlight into electricity just as efficiently as their glass-based counterparts. In this case this structure has been applied on glass but it could be used on any material, such as fabric or paper.
“It could be so light that you don’t even know it’s there, on your shirt or on your notebook. These cells could simply be an add-on to existing structures. [...] We have a proof-of-concept that works" said professor Bulović. "How many miracles does it take to make it scalable? We think it's a lot of hard work ahead, but likely no miracles needed”.