A relatively new type of solar cell based on a perovskite material is good not just at absorbing light but also at emitting it. According to the new findings, these ‘wonder cells’ can also produce cheap lasers.
Perovskite solar cells have already reached 17% efficiency after a mere two years of research – transforming prospects for cheap large-area solar energy generation.
Now, researchers from Professor Sir Richard Friend’s group at Cambridge’s Cavendish Laboratory – working with Snaith’s Oxford group – produced an optically driven laser which goes on to prove these cells “show very efficient luminescence”, by sandwiching a thin layer of the lead halide perovskite between two mirrors.
Essentially, if a material excels at converting light to electricity, then it will be good at converting electricity to light too. Their lasing properties raise hopes for even higher solar cell efficiencies.
“This first demonstration of lasing in these cheap solution-processed semiconductors opens up a range of new applications,” said lead author Dr Felix Deschler of the Cavendish Laboratory. “Our findings demonstrate potential uses for this material in telecommunications and for light emitting devices.”
“We were surprised to find such high luminescence efficiency in such easily prepared materials. This has great implications for improvements in solar cell efficiency,” said Michael Price, co-author from the group in Cambridge.