Singlet fission breaks 'ceiling' of solar cells for 130% quantum yield

Key Points:

• Researchers from Kyushu University and Johannes Gutenberg University Mainz have surpassed the traditional solar energy conversion limit by achieving a quantum yield of 130% using a novel “spin-flip” emitter, proving solar systems can generate more energy carriers than photons absorbed.
• The breakthrough overcomes the Shockley–Queisser limit by employing singlet fission (SF), a process that splits one high-energy exciton into two lower-energy triplet excitons, theoretically allowing one photon to produce two excitons.
• The team developed a molybdenum-based metal complex that selectively harvests multiplied triplet excitons by flipping electron spins, thereby avoiding energy loss through Förster resonance energy transfer (FRET) and enabling enhanced quantum efficiency.
• While the current results were demonstrated in solution, the researchers aim to transition the technology into solid-state devices, potentially leading to ultra-efficient solar panels, LEDs, and quantum computing applications with significantly reduced heat loss.
• This advancement could revolutionize solar energy by enabling panels that produce substantially more electricity from the same sunlight, accelerating the shift away from fossil fuels.