Niklas Pyrlik, a master’s student of the group FS-PETRA at DESY and the University of Hamburg, has been honoured with the “Best XRD Poster” award at the Denver X-ray Conference, having taken place in Colorado (USA) from August 5 to 9, 2024.
With short interruptions, Niklas Pyrlik has been part of the group since 2020 and is now close to finishing his master’s degree in physics at the University of Hamburg. The title of his award-winning poster presentation was “Synchrotron-Based Multi-Modal Imaging Unveils Structure – Composition – Performance Correlations in CIGS Solar Cells”.
“Cu(In,Ga)Se2, or short CIGS, is a polycrystalline compound semiconductor. Thanks to its direct bandgap, CIGS solar cells can be made 100 times thinner than traditional silicon solar cells. However, these solar cells are plagued by inhomogeneities at grain boundaries that impede their performance,” explains Niklas Pyrlik. “That is why we want to look at single grains and in this study, we have successfully mapped out around 500 of them with scanning X-ray diffraction. We can directly correlate structural effects on the single-grain level with the elemental and performance distribution that are measured at the same time.”
DESY scientist Michael Stuckelberger, who supervises Pyrlik’s work together with Christian Schroer, leading scientist at DESY and professor at the Universität Hamburg, agrees: “This kind of comprehensive understanding is pivotal for optimising manufacturing processes, and the award underscores our commitment to excellence in scientific research advancing photovoltaic technologies.”
“This was my first scientific conference abroad and an all-in-all exciting opportunity,” Pyrlik cheerfully adds.
Currently, the group works on extending the presented X-ray techniques to perovskite solar cells, where intra-grain strain and its effect on performance and longevity remain elusive. Stuckelberger adds: “With X-ray excited optical luminescence complementing the suite of X-ray modalities, users of PETRA III will be able to map not only the bandgap but also the charge carrier lifetime of semiconductors embedded in these intricate devices.” This photon-hungry technique will greatly benefit from the upgrade of PETRA III to PETRA IV, allowing for measurements of novel materials that are out of reach today.