Speaker
Description
Inorganic halide perovskites are promising for optoelectronic applications, offering greater thermal stability over hybrid counterparts but are prone to phase instabilities. Phase stability can be improved by compositional engineering, e.g., varying the Cs/Pb and I/Br ratio. Combinatorial vacuum coevaporation allows the investigation of the large compositional space of Cs(Sn,Pb)(I,Br)3 in the search for lead-free absorber layers of high electronic quality and stability.
To accelerate material exploration, we have automated the characterization and are able to characterize 600 samples on a 5 cm x 5 cm sample library by UV-Vis, PL, TRPL, conductivity, and XRF within one day after sample deposition in a glove-box based custom-built evaporation system. All measurements are performed either in an inert atmosphere or vacuum, preventing ambient-induced degradation.
Data from our experiments are directly fed into a specially customized NOMAD Oasis platform, shaped to meet our research specifications. This data management system not only enables large-scale data integration but also produces data that is ready for ML/AI analysis . By generating ML/AI-ready datasets, we facilitate the evaluation of critical material properties such as absorption coefficient, band gap, photoluminescence quantum yield, quasi-Fermi level splitting, recombination lifetime, doping density, and carrier mobility. Coupled with device simulation and empirical models, this approach allows us to rapidly predict solar cell performance from these material properties, typically within a day of synthesis.
Our methodology emphasizes the interoperability of the data artifacts generated, by ensuring compliance with data models established by a broad community of specialists. Specifically, the data fed into NOMAD Oasis adheres to models and base classes developed as part of an ontology for vacuum deposition. This approach not only aligns with the FAIR-data principles but also facilitates the reuse of data across various platforms and applications.