Young investigator group at HZB: Scaling perovskite cells
Dr. Eva Unger leads the Young Investigator Group Hy-Per-FORME. © privat
The new Young Investigator Group Hy-Per-FORME led by Dr. Eva Unger is working on scaling all processing steps to enable manufacturing of perovskite solar cells on larger areas, thus brigding he gap between lab and industry.
Dr. Eva Unger is starting a Young Investigator Group (YIG) at HZB, co-financed by the Federal Ministry for Education and Science (BMBF). The activities of the Unger group will be an important contribution within the newly-founded HySPRINT Innovation lab aiming at the realization of large-area, stable and efficient hybrid tandem device technology based on a combination of established silicon photovoltaic technology and emerging perovskite semiconductor devices.
To achieve this goal, developing and optimizing scalable deposition methods for the recently evolved hybrid perovskite semiconductors is one of the key aspects. The YIG of Unger therefore focusses on the formation and scaling the deposition of hybrid perovskite semiconductors using slot-die coating and ink-jet printing as a solution-based processing technology.
Originally from Germany, Eva Unger did her PhD at Uppsala University, Sweden and carried out postdoctoral work at Stanford University and Lund University through a stipend from the swedish Marcus and Amalia Wallenberg Foundation. Prior to starting the YIG, she has been working as a visiting researcher at Helmholtz Center Berlin funded by an International Career Grant co-funded by the Swedish Research Council and Marie-Skłodowska-Curie Actions. She will be co-affiliated with Lund University, Sweden and aims to strengthen cooperations with Lund University, Vrije Universiteit Amsterdam and the Universities in Berlin and Brandenburg.
- CIGS-perovskite tandem cell achieves record efficiency of 25.5 %A Berlin-based team from HZB and Center for the Science of Materials Berlin (CSMB) at the Humboldt-Universität zu Berlin has set a new record for a tandem solar cell. Using a combination of a CIGS semiconductor layer and perovskite, along with several optimised intermediate layers, they were able to convert 25.5% of sunlight into electrical energy. The previous record for this combination of materials and this size of cell stood at 24.6%. The new record has been certified and is visible in the prestigious Solar Cell Efficiency Tables (the "Green Tables"), which serve as the definitive ledger for the global photovoltaic community.
- Disorder creates new properties in compound semiconductorsAn international research team has demonstrated that the intrinsic disorder of the compound semiconductor CuInSnS₄ can be exploited to influence its optical properties. While the atomic vibrations also sense the local disorder, their response is averaged over many different local environments and therefore appear isotropic, as expected for a cubic crystal. In contrast, the optical excitations, known as excitons, are much more sensitive to the local arrangement of atoms. Surprisingly, they show a direction-dependent optical response even though the average crystal structure is cubic. These findings shed new light on the relationship between disorder and material properties, opening up new options for targeted 'disorder engineering' in optoelectronic and photocatalytic devices.
- Perovskite solar cells: Predictions of long-term stabilityReliable statements about the long-term stability of perovskite solar cells are still difficult to make. However, a new study by Dr Carolin Ulbrich’s team, published in the renowned journal Joule, highlights which methods are useful for this purpose and identifies areas where further research is needed.