Tiburtius Prize for Eike Köhnen
Eike Köhnen (center) was awarded with the Tiburtius Prize for his outstanding dissertation on tandem solar cells with perovskites. In the team of Prof. Steve Albrecht (left, TU Berlin and HZB) he was involved in several world records. Prof. Michael Lehmann (TU Berlin) gave the laudatory speech.
On Tuesday, 6 December 2022, Dr. Eike Köhnen received the Tiburtius Prize (First Place) for outstanding dissertations. Eike Köhnen has contributed to significantly increasing the efficiency of tandem solar cells made of perovskite and silicon, to the point of setting world records.
Eike Köhnen worked on so-called tandem solar cells, a new type of photovoltaic technology that promises significantly higher efficiencies. In Prof. Steve Albrecht's team (TU Berlin and HZB), he combined conventional silicon solar cells with a perovskite cell and analysed with state-of-the-art methods how losses can occur. These insights helped to increase the efficiency of such tandem solar cells to over 29 %. This value was an absolute world record for more than eight months.
Köhnen also obtained two patents as a PhD student. His thesis was assessed with the top mark summa cum laude. In Albrecht's team, Eike Köhnen was also active in science communication and maintained a lively Twitter account.
"The Tiburtius Prize is an outstanding recognition of this excellent dissertation and Eike's pioneering work in the development of solar cells," says Prof. Steve Albrecht, who supervised the PhD-thesis. Co-supervisor Prof. Bernd Rech, who heads the Helmholtz-Zentrum Berlin as scientific director, adds: "Eike Köhnen has played a major role in our internationally visible successes with tandem solar cells made of perovskite and silicon. I congratulate him on this fine award."
The award is named after Professor Joachim Tiburtius, who was Senator for National Education in Berlin from 1951 to 1963. The State Conference of Rectors and Presidents of Berlin Universities (LKRP) awards three prizes annually, as well as an additional three recognition prizes, to doctoral students at Berlin universities for outstanding dissertations
Title of the dissertation by Eike Köhnen: Optical and Electrical Optimization by Advanced Characterization of Monolithic Perovskite/Silicon Tandem Solar Cells.
arö
https://www.helmholtz-berlin.de/pubbin/news_seite?nid=24327;sprache=en
- Copy link
-
Battery research with the HZB X-ray microscope
New cathode materials are being developed to further increase the capacity of lithium batteries. Multilayer lithium-rich transition metal oxides (LRTMOs) offer particularly high energy density. However, their capacity decreases with each charging cycle due to structural and chemical changes. Using X-ray methods at BESSY II, teams from several Chinese research institutions have now investigated these changes for the first time with highest precision: at the unique X-ray microscope, they were able to observe morphological and structural developments on the nanometre scale and also clarify chemical changes.
-
BESSY II: New procedure for better thermoplastics
Bio-based thermoplastics are produced from renewable organic materials and can be recycled after use. Their resilience can be improved by blending bio-based thermoplastics with other thermoplastics. However, the interface between the materials in these blends sometimes requires enhancement to achieve optimal properties. A team from the Eindhoven University of Technology in the Netherlands has now investigated at BESSY II how a new process enables thermoplastic blends with a high interfacial strength to be made from two base materials: Images taken at the new nano station of the IRIS beamline showed that nanocrystalline layers form during the process, which increase material performance.
-
Martin Keller elected new president of the Helmholtz Association
The Helmholtz Association has appointed internationally respected US-based scientist Martin Keller as its new president. Her has lived in the United States for nearly three decades, during which he has held various scientific leadership roles at prominent institutions. Since 2015, Keller has directed the National Renewable Energy Laboratory (NREL) in Golden, Colorado. His term begins on 1.11. 2025.