PINNACLE is a highly interdisciplinary research project encompassing elements from physics, chemistry, material science, and engineering. Accordingly, a diverse team of young, highly motivated researchers with expertise ranging from inorganic chemistry to spectroscopy, theoretical physics, and device engineering worked together to fulfil the project's goals of enhancing the understanding of halide perovskite nanocrystals and using this knowledge to push them further towards commercialization. Due to the Corona pandemic, the overall goals had to be shifted away from the device application and more toward the fundamental understanding of perovskites and mitigation of the material’s current limitations.
Toward the fundamental understanding, we extensively investigated strongly confined halide perovskite NCs, focusing mainly on hitherto less explored anisotropic NCs such as nanorods and nanoplatelets. Incorporating machine learning and various characterization methods (X-ray scattering, electron microscopy, in situ optical spectroscopy) we have been able to develop reproducible, highly efficient syntheses working in ambient conditions for the specific fabrication of thickness-controlled 1D and 2D nanocrystals. These provide an excellent basis for studying the intricate interplay between morphology, composition and resulting properties of halide perovskites. We have probed these with complex temperature-resolved ultrafast optical spectroscopy, revealing important details on, e.g. excitonic fine structure, phonon-coupling exciton-exciton annihilation. The micellar-encapsulated NCs have also been significantly enhanced and now con be produced with strong emission spanning the visible wavelength and superior stability toward environmental degradation. Post-processing cross-linking leads to extremely stable films and heterostructures. With the resources and research environment provided through PINNACLE, we have now shifted our focus toward lead-free perovskite alternatives and exploring materials for photocatalysis.
This work so far has culminated in a number of invited and contributed talks for the PINNACLE team, with several awards for students’ presentations, and many high-impact papers. We have submitted two patents and are contemplating a proof-of-concept grant application to explore the commercial viability of our approaches.
