Collaborative Research Centre “Nanoscale Metals” raises 11 million euros
Licht wird durch den Nanopartikel fokussiert und die Energie lokal in verschiedene Formen umgewandelt, die dann Chemische Transformation antreiben. © Felix Stete
Several HZB research teams are participating in the new SFB 1636 "Elementary processes of light-driven reactions on nanoscale metals".
Research on Nansoscale Metals
“We are excited and look forward to the new synergies that can arise from this,” says Prof. Matias Bargheer, who is one of the spokespersons for the new Collaborative Research Centre, led by University of Potsdam. The HZB scientists Renske van der Veen, Yan Lu and Alexander Föhlisch are also involved, in addition to the team of Bargheer, who heads a joint research group at the University of Potsdam and HZB.
The research project aims to help understand the elementary processes that trigger light-controlled chemical reactions on metals at the nanoscale. “There are still many unanswered questions at this fascinating transition between physics and chemistry and we can already apply our concepts to organic coupling reactions and polymerisations, e.g. to functionalise nanoparticles asymmetrically,” says Prof. Dr. Matias Bargheer, talking about the struggles as well as the perspectives of their collaborative research.
- Magnetic imaging: Micro-flowers increase the local magnetic fieldMaterials with magnetic nanostructures have many potential applications such as in spintronics. To explore such materials, nanoscale magnetic-sensitive imaging techniques are very useful, but up to now only weak magnetic fields could be applied during the imaging process. Now an international collaboration led by Dr. Sergio Valencia, HZB, has developed an approach that overcomes this limitation. The team designed tiny magnetic flux concentrators (MFCs), into which the sample is placed. The geometry of the MFCs resembles a flower with a number of petals which focus the applied magnetic field into its center. This greatly expands the magnetic field range available during imaging, and so the range of magnetic systems that can be investigated. The micro-flowers, enhancing magnetic fields locally, can find application in different nanometric magnetic microscopy techniques.
- 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.