A Seoul research team says tiny gold “supraballs” could help solar devices capture much more of the sunlight they currently miss.
Researchers from Korea University and the Korea Institute of Science and Technology (KIST) report that the material absorbed more than 90% of solar wavelengths in simulations and reached about 88.8% average solar absorption when coated onto a commercial thermoelectric generator.
That was nearly double the roughly 45% seen with a conventional gold nanoparticle film, and the coated device produced 2.4 times more power.
Why this solar technology matters
Why does that matter? Because a lot of usable solar energy still slips away. Many nanoparticle-based absorbers perform mainly in the visible range, leaving other wavelengths on the table.
In practical terms, that means energy that could help power devices or produce heat is simply lost, even as homes and businesses keep chasing lower electric bills. The Seoul team’s approach tries to widen that capture window with a process that works in ordinary room conditions, without clean rooms or extreme temperatures.
The idea is clever, but also surprisingly simple. The gold nanoparticles self-assemble into tiny spheres, and those spheres trap light through several overlapping optical effects. Researchers tuned the size of the spheres, then formed a film by drying a liquid solution directly onto a commercial thermoelectric generator.
That may be the real hook here. The big number grabs attention, sure, but the manufacturing angle is just as important. A material that only works in a pristine lab is one thing. A coating that can be laid down from solution is another.
What this means for solar thermal and energy systems
Still, this is not a magic fix for every rooftop panel tomorrow. The demonstration was done on a thermoelectric generator under simulated sunlight, so for the most part this should be seen as an early but promising step toward solar thermal, photothermal, and related energy systems.
As Seungwoo Lee said, “Our plasmonic supraballs offer a simple route to harvesting the full solar spectrum.” If later tests hold up at scale, the payoff could be easy to understand. More of the sun gets used, and less of it goes to waste.
The press release was published by the American Chemical Society.
