Tin-based solar panels could trap heat for 1,000 times longer

A tin-based solar panel material could help researchers overcome a long-standing limit in solar energy production, according to a report by TechRadar.

Solar panels use sunlight photons to energize electrons. The most energetic photons create “hot” electrons that could generate more electricity, but they normally cool rapidly and lose their energy as heat before it can be captured.

Previous research found that the material can keep heat from hot electrons trapped for around 1,000 times longer. A team from the University of Groningen in the Netherlands used computer simulations and experimental measurements to investigate why.

The researchers identified two effects working together. A hot phonon bottleneck allows electrons to reabsorb thermal energy as their surroundings heat up. The Burstein-Moss effect fills the lowest available energy states, slowing the cooling of other hot electrons.

The findings suggest that the material could eventually help solar panels exceed the long-standing 33% conversion limit. The researchers said in their paper, published in ACS Energy Letters, that the electronic, phononic, and chemical conditions must operate together under high-injection conditions for practical devices. Commercial scale-up remains a future possibility, not an established result.