Press Review

PV – Magazine – 20 December 2022

A group of researchers from Helmholtz-Zentrum Berlin has achieved a new efficiency world record with a tandem solar cell. It converts 32.5 percent of the incident solar radiation into electrical energy.

The current efficiency world record for tandem solar cells consisting of a silicon bottom cell and a perovskite top cell is once again held by Helmholtz-Zentrum Berlin (HZB). It is 32.5 percent and was officially confirmed by the certifying institute European Solar Test Installation.

“This is a really big leap forward that we didn’t foresee a few months ago,” said Steve Albrecht from HZB’s perovskite tandem solar cell department. “All the teams involved at HZB, especially the teams from the PV Competence Centre (PVcomB) and the HySPRINT Innovation Lab, have worked together excellently and with great dedication here.”

His team used an improved perovskite compound and a modification of the surface. Postdocs Silvia Mariotti and Eike Köhnen, both authors of the study, developed an interface modification that largely suppressed charge recombination losses. Furthermore, they applied special analytical measurement methods to better understand the fundamental processes. These developments were then successfully transferred to tandem solar cells and combined with further optical improvements by Master’s student Lea Zimmermann.