A team of Cambridge scientists, in collaboration with Oxford University AMOLF FOM Institute in Amsterdam, could lead to a revolution in the efficiency of solar power, with the development of perovskite-based panels capable of 'recycling light'.
Solar cells work by absorbing photons from the sun to create electrical charges. However, the process also works in reverse, because when the electrical charges recombine, they can create a photon. The research shows perovskite cells have the extra ability to re-absorb these regenerated photons – a process known as "photon recycling".
The study involved shining a laser on to one part of a 500 nanometre-thick sample of perovskite. As it emits light when they come into contact, the team was able to measure photon activity inside the perovskite sample based on the light it emitted. The researchers stated that "The fabrication methods that would be required to exploit this phenomenon are not complicated, and that should boost the efficiency of this technology significantly beyond what we have been able to achieve until now."
They also explained that the low-energy component enables charges to be transported over a long distance, but the high-energy component could not exist unless photons were being recycled;