Scientists from HZB and Humboldt University Berlin have reported a CIGS-perovskite tandem cell that sets a record with an efficiency of 24.6%, certified by the independent Fraunhofer Institute for Solar Energy Systems.
The team's new tandem solar cell combines a bottom cell made of CIGS with a top cell based on perovskite. By improving the contact layers between the top and bottom cells, they were able to increase the efficiency to 24.6%. This cell was the result of a successful team effort: the top cell was fabricated by TU Berlin master's student Thede Mehlhop under the supervision of Stefan Gall. The perovskite absorber layer was produced in the joint laboratory of HZB and Humboldt University of Berlin. The CIGS sub-cell and contact layers were fabricated by HZB researcher Guillermo Farias Basulto. He also used the high-performance cluster system KOALA, which enables the deposition of perovskites and contact layers in vacuum at HZB.
‘At HZB, we have highly specialized laboratories and experts who are top performers in their fields. With this world record tandem cell, they have once again shown how fruitfully they work together,' says Prof. Rutger Schlatmann, spokesman for the Solar Energy Department at HZB.
We are confident that CIGS-perovskite tandem cells can achieve much higher efficiencies, probably more than 30%," says Prof. Rutger Schlatmann.
