Slovenian president awards HZB scientist with "Apple of Inspiration"
Marko Topic, Bernd Rech, Janez Krc, Benjamin Lipovsek, Steve Albrecht, Marko Jost, Borut Pahor (f.l.t.r) © Faculty of electrical engineering University of Ljubljana
© Joze Suhadolnik
Marko Jošt, Steve Albrecht and Bernd Rech, researchers at the Helmholtz-Zentrum Berlin (HZB) and the Technische Universität Berlin (TUB) receive a rare award today, 19 December 2018. In the slovenian Grand Hall of Presidential Palace, the Slovenian President, Borut Pahor, presents them with the "Apple of Inspiration". It honours achievements in culture, science, sport and society. The Berlin scientists are the first foreigners who receive the prize together with colleagues from the University of Ljubljana.
The teams from Ljubljana and Berlin are honored for their long-standing collaboration, which has led to milestones in the development of perovskite solar cells. This is documented, for example, by a joint publication in the renowned journal Energy and Environmental Science on an efficiency record for a monolithic tandem solar cell made of silicon and perovskite layers.
Dr. Marko Jošt, who was the first author of the study and contributed significantly to the joint results, received his doctorate both at the University of Ljubljana and at the TUB. Today he is a postdoctoral researcher at the HZB.
The excellent international cooperation not only inspires young scientists in Slovenia, but also contributes to further strengthening research into alternative energy sources, according to the Slovenian government. "International cooperation and the results achieved are of great importance for society. They help to find solutions for a sustainable energy turnaround and thus also to fight against climate change and thus secure our livelihoods".
Prof. Steve Albrecht, head of a BMBF-funded junior research group at the HZB and junior professor at the TUB, is the coordinator of the mentioned study. In cooperation with the Helmholtz Innovation Lab HySPRINT and the Photovoltaic Competence Centre PVcomB, he develops and analyses the very complex tandem cells with the aim of leading them to a greater technological maturity.
Prof. Bernd Rech, solar researcher and currently acting scientific director of the HZB, initiated the German-Slovenian cooperation together with the Slovenian professor Marko Topic. Among other things, he was a visiting professor at the University of Ljubljana in 2014. The close cooperation continues to this day. Marko Jost, the joint doctoral student at the time, is now a postdoctoral researcher in Steve Albrecht's group.
- 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.