Researchers at the Massachusetts Institute of Technology have developed the thinnest solar cells in the world, exemplifying it by putting a solar cell on top of a bubble without popping it.
Scientists at MIT have developed organic cells by growing a polymer substrate film inside a room temperature vacuum. The new development could eventually be used to power the next generation of portable technologies and also on almost every type of surface or material, making it extremely versatile for today’s modern applications. Amazingly enough, the solar cells can also be created entirely in just one big process.
The development of the solar cells was published in the journal Organic Electronics and Professor Vladimir Bulovic authored it along with research scientist Annie Wang and doctoral student Joel Jean. The new process described in the publishing illustrates how the new approach to creating solar cells is not only groundbreaking but also could change the way power cells work.
The key to the new approach is to make the solar cell, the substrate that supports it and the protective overcoat in just one process, says Professor Bulovic. The team in charge of the initial experiments used a common flexible polymer called parylene for the substrate and the over coating while the light-absorbing layer would be made of an organic material called DBP.
“The demonstration by the MIT team is almost an order of magnitude thinner and lighter,” says professor Max Shtein at the University of Michigan. “The new solar cell has tremendous implications for maximizing power-to-weight ratio, and for the ability to simply laminate photovoltaic cells onto existing structures.”
The substrate shows to be one of the features of the new process, as it doesn’t need to be removed for cleaning during its fabrication. This, in turn, would limit the exposure to contaminating agents or other fragments that could pollute the cell and lower its overall performance. The team at Massachusetts Institute of Technology implemented a vapor deposition technique in order to develop the substrate and the solar cells.
New approaches, better results
The process would involve the use of the polymer called parylene, which is a commercially available plastic coating normally used to protect implanted biomedical devices such as in bypass operations. The resulting devices, including the solar cells, the substrate and the over coating would be around two micrometers thick, impressively enough considering that’s just one-fiftieth of a human hair’s thickness.
Another feature of the new process described by Professor Bulovic is that the entire manufacturing process can take place in a vacuum chamber and the use of solvents – frequently use in current solar cells manufacturing processes – is no longer needed. Current solar cell processes require high temperatures and harsh chemicals in order to fabricate the cells, yet the initial proof-of-concept experiment made by the scientist team shows that can soon be in the past.
Source: MIT