Pushing Past Limits: Tandem Solar Cells Achieve Over 20% Efficiency

A tandem cell was constructed using perovskite and antimony selenide.
A research team has demonstrated for the first time a proof-of-concept tandem solar cell using antimony selenide as the bottom cell material and a wide-bandgap organic–inorganic hybrid perovskite material as the top cell material. The device achieved a power conversion efficiency of over 20 percent. This study shows that antimony selenide has great potential for bottom cell applications.

The research was recentlys published in the journal Energy Materials and Devices.

Photovoltaic technology, which harnesses sunlight and converts it into electricity, is popular because it provides a clean, renewable energy source. Scientists continue to work to improve the power conversion efficiency, or the measure of efficiency, in solar cells. They have achieved power conversion efficiencies of over 20 percent in conventional single-junction solar cells. To achieve power efficiency above the Shockley-Queisser limit in single-junction solar cells would require much greater costs. However, the Shockley-Queisser limit of single-junction solar cells can be overcome through the fabrication of tandem solar cells. With tandem solar cells, researchers are able to gain a higher energy efficiency by stacking solar cell materials on top of each other.