Dissertation Prize Adlershof 2021 goes to Amran Al-Ashouri
Congratulations: Amran-Al Ashouri (3rd from right) wins the 2021 Dissertation Award. A total of three nominees gave exciting presentations at the event. © IGAFA/Matthias Brandt
The world record cell from HZB. With his research, Amran Al-Ashouri made an important contribution to this success. © Amran Al-Ashouri /HZB
02:15
On February 17, 2022, the Adlershof Dissertation Prize was awarded for the 20th time. Dr. Amran Al-Ashouri (3rd from right) from the HZB young investigator research group "Perovskite tandem solar cells" received the prize endowed with 3,000 euros. The physicist is researching how new organic contact layers can be used to optimize highly efficient perovskite silicon tandem solar cells.
Today's solar modules are mainly made of silicon, and it is no longer possible to significantly increase their efficiency. For some years now, perovskites have therefore become an important focus of research. These semiconductor compounds efficiently convert sunlight into electrical energy. In particular, they can be excellently combined with silicon solar cells to form tandem solar cells that can use sunlight much more efficiently.
In his doctoral thesis, Amran Al-Ashouri developed new organic contact layers for perovskite silicon tandem solar cells and researched the fine-tuning of the electrical interfaces for minimal charge carrier losses. The tandem solar cells realised with several teams at HZB achieved record efficiencies, due to this optimization (see news "World record again at HZB"). Due to their low resource and cost requirements, tandem solar cells represent an important technology that can accelerate the energy transition.
"My PhD thesis is about a novel technology that can boost solar cells. Our goal is that the results in tandem solar cells can be used by industry," Amran Al-Ashouri said at the award ceremony. He said he deliberately chose this research topic. "The technologies for combating the climate crisis are mostly available, however, innovation from research drives the transition and makes their future use more effective."
The Dissertation Award is jointly sponsored and organized each year by the IGAFA e. V. research network, Humboldt University in Berlin and WISTA Management GmbH. This year there were nine applicants, of which three made it to the final selection. The nominees presented their scientific achievements in a vivid way within 15 minutes.
About Amran Al-Ashouri
Dr. Amran Al-Ashouri studied physics at the University of Duisburg-Essen. From September 2017 to February 2021, he completed his doctorate at HZB and the Technical University of Berlin. Since then, the physicist has been working as a postdoc at Helmholtz-Zentrum Berlin in the young investigator research group "Perovskite tandem solar cells".
- 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.