E-MRS: Prizes for two PhD students at HZB
PhD students Hannes Hempel and Sara Niedenzu have earned awards at the E-MRS 2018.
In her first year of doctoral studies, Sara Niedenzu has been awarded a Poster Prize.
At the spring meeting of the European Materials Research Society from 18-22 June 2018 in Strasbourg, Hannes Hempel received the prize for the best talk and Sara Niedenzu was awarded for her poster. Both are PhD students at the MatSEC graduate school at HZB. The E-MRS spring conference is the largest materials research conference in Europe with 2,500 participants.
With his talk, Hannes Hempel applied for the prize of the symposium on thin-film chalcogenides in photovoltaics, which was attended by about 350 experts. The physicist, who is working on his doctorate in Thomas Unold's team, explained the influence of "bandtails" on the transport properties and recombination of charge carriers in polycrystalline kesterites. "I was one of four finalists in the final selection, where we were able to present our career, our role in the team and once again the main results. After all, me and another researcher won," explains Hempel, who is not only pleased about the recognition but also about the prize money of 450 €. In the future he will set up the new laboratory of Thomas Unold for terahertz spectroscopy, in which ultra-fast dynamics of the crystal lattice can be characterized in addition to mobility and lifetime of charge carriers.
Sara Niedenzu presented the crystal structures of chalcogenide semiconductors with larger band gaps on her poster. It deals with the synthesis of polycrystalline powders of different mixing series and the structural characterization of these materials, which are used as materials for energy conversion in photovoltaics. Sara Niedenzu has just finished her first year in the team of Prof. Susan Schorr, who congratulates her: "It's great to receive an award at this early stage of the doctorate at an international conference", Susan Schorr says.
Title of talk given by Hannes Hempel: “Charge Carrier Dynamics in Tail States of polycrystalline Cu2ZnSnSe4“.
Publication on the topic: “Intragrain charge transport in kesterite thin films - Limits arising from carrier localization“
Poster by Sara Niedenzu: “Structural characterization of wide bandgap Cu‐Zn‐IV‐chalcogenide based semiconductors”
Link to E-MRS 2018
- Self assembling monolayer can improve lead-free perovskite solar cells tooTin perovskite solar cells are not only non-toxic, but also potentially more stable than lead-containing perovskite solar cells. However, they are also significantly less efficient. Now, an international team has succeeded in reducing losses in the lower contact layer of tin perovskite solar cells: The scienstists identified chemical compounds that self-assemble into a molecular layer that fits very well with the lattice structure of tin perovskites. On this monolayer, tin perovskite with excellent optoelectronic quality can be grown, which increases the performance of the solar cell.
- Berlin Science Award goes to Philipp AdelhelmBattery researcher Prof. Dr. Philipp Adelhelm has been awarded the 2024 Berlin Science Award. He is a professor at the Institute of Chemistry at Humboldt University in Berlin (HU) and heads a joint research group at HU and the Helmholtz Zentrum Berlin (HZB). The materials scientist and electrochemist is investigating sustainable batteries, which play a key role in the success of the energy transition. He is one of the leading international experts in the field of sodium-ion batteries.
- Long-term test shows: Efficiency of perovskite cells varies with the seasonScientists at HZB run a long-term experiment on the roof of a building at the Adlershof campus. They expose a wide variety of solar cells to the weather conditions, recording their performance over a period of years. These include perovskite solar cells, a new photovoltaic material offering high efficiency and low manufacturing costs. Dr Carolin Ulbrich and Dr Mark Khenkin evaluated four years of data and presented their findings in Advanced Energy Materials. This is the longest series of measurements on perovskite cells in outdoor use to date. The scientists found that standard perovskite solar cells perform very well during the summer months, even over several years, but decline in efficiency during the darker months.