If we want to implement this in a solar cell, we need to understand more about why and how singlet exciton fission occurs in the first place.
- Andrew Musser
The underlying mechanism behind an enigmatic process called “singlet exciton fission”, which could enable the development of significantly more powerful solar cells, has been identified by scientists in a new study.
The process is only known to happen in certain materials, and occurs when they absorb light. As the light particles come into contact with electrons within the material, the electrons are excited by the light, and the resulting “excited state” splits into two.
If singlet exciton fission can be controlled and incorporated into solar cells, it has the potential to double the amount of electrical current produced from highly energetic blue and green light, capturing a great deal of energy that would normally be wasted as heat and significantly enhancing the efficiency of solar cells as a source of green energy. Until now, however, scientists have not really understood what causes the process, and this has limited their ability to integrate it into solar devices.
Writing in the journal Nature Physics, a team of researchers shows that there is an unexpected link between the splitting process and the vibration of the molecule that occurs when light comes into contact with the electrons. This vibration is thought to drive the production of two excited electrons, revealing for the first time how singlet exciton fission happens.
The study was carried out by researchers from the Cavendish Laboratory at the University of Cambridge, and the University of Oxford. As well as solving a hitherto mysterious problem of quantum physics, it potentially provides a basis on which new singlet fission materials could be developed for use in solar cells.
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Image: "Green Power". While conventional solar cells use silicon, it is possible that other materials could eventually be used that would increase their efficiency.
Credit: Martin Abegglen on Flickr
Reproduced courtesy of the University of Cambridge
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