Researchers at Korea University have taken a step toward lowering the barrier to more efficient and cost-effective renewable energy generation by using gold nanospheres designed to capture light across the solar spectrum.
Hung Lo others. We introduce plasmonic colloidal superballs, solution-processable aggregates of gold nanospheres, as a robust and versatile platform for broadband solar energy harvesting. Image credit: Hung Lo others., doi: 10.1021/acsami.5c23149.
Scientists are researching materials that absorb light across the solar spectrum to improve solar energy harvesting.
Gold and silver nanoparticles have been proposed as a solution because they are easy to manufacture and cost-effective, but the light absorption of current nanoparticles is limited to visible wavelengths.
To capture additional wavelengths, including near-infrared light, Korea University researcher Seungwoo Lee and colleagues propose the use of self-assembled gold superballs.
These structures are composed of gold nanoparticles that aggregate to form small spheres.
The diameter of the superball was adjusted to maximize absorption of wavelengths found in sunlight.
The researchers first used computer simulations to optimize the design of each individual Superball and predict the performance of the Superball film.
The simulation results showed that the superball should absorb more than 90% of sunlight’s wavelengths.
The scientists then created a film of gold superballs by drying a solution containing the structures on the surface of a commercially available thermoelectric generator, a device that converts light energy into electricity.
Films were made in ambient room conditions. No clean room or extreme temperatures required.
In a demonstration using an LED solar simulator, the average solar absorption rate of the superball-coated thermoelectric generator was approximately 89%, nearly twice that of a thermoelectric generator with a conventional membrane made from a single gold nanoparticle (45%).
“Our plasmonic superball provides an easy way to collect the entire solar spectrum,” Dr. Lee said.
“Ultimately, this coating technology has the potential to significantly lower the barrier for high-efficiency solar and photothermal systems in real-world energy applications.”
of the team work appear in the diary ACS Applied Materials & Interfaces.
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Ro Kyung Hoon others. 2026. Plasmonic Supraball for Scalable Broadband Solar Energy Generation. ACS Application Meter. interface 18 (1): 2523-2537;doi: 10.1021/acsami.5c23149