Dr. Philip Schulz delivered an invited talk on "Interface Defect Formation in Halide Perovskite Semiconductors"

January 31, 2025

Dr. Philip Schulz, Research Director at the French National Centre for Scientific Research (CNRS), and principal investigator at the Institut Photovoltaïque d'Île-de-France (IPVF) on the Paris Saclay campus, recently delivered an insightful talk titled "Interface Defect Formation in Halide Perovskite Semiconductors" as part of the CeNS Nanocolloquium series.

His presentation focused on hybrid organic-inorganic metal halide perovskites (MHPs) and the crucial role of interface engineering in enhancing both performance and stability. As the interfaces between perovskite films and charge transport layers (CTLs) govern device efficiency and long-term reliability, understanding their chemical and electronic properties is essential.

Dr. Schulz provided a detailed discussion on the challenges of analyzing these interfaces using photoemission spectroscopy (PES) due to complex chemical interactions at buried interfaces. He showcased synchrotron- and lab-based X-ray photoelectron spectroscopy (XPS) and hard X-ray photoelectron spectroscopy (HAXPES) experiments to investigate MHP interfaces with oxide CTLs, such as SnO₂ and NiO layers grown via atomic layer deposition (ALD). His findings revealed the formation of new chemical species and unfavorable changes in energy level alignment, which negatively impact device performance.

In concluding, Dr. Schulz addressed the broader implications of PES methods in MHP research, including the effects of X-ray irradiation-induced damage and the fascinating phenomenon of stimulated self-healing in formamidinium lead bromide (FAPbBr₃).

His talk provided valuable insights into the fundamental interface chemistry of perovskite-based solar cells, reinforcing the importance of advanced spectroscopic techniques in optimizing next-generation photovoltaic materials.