Innovative Catalyst Platform Advances Understanding of Working Catalysts
© FHI
A novel catalyst platform, known as Laterally Condensed Catalysts (LCC), has been developed to enable design and analysis of the functional interface connecting the active mass to its support. This interface not only influences the chemical properties of the reactive interface but also controls its stability and hence the sustainability of the catalytic materials. The development was significantly supported by the use of operando spectroscopy at the BESSY II synchrotron, which made it possible to observe and understand the dynamic processes and structures under reaction conditions.
Unrestrained combinations in composition between active phase and support enable for example direct energy transfer to the reactive interface in electrocatalysis or electrical heating. The physical synthesis methodology within the FHI-HZB CatLab project, taken from solar cell technology, gives access to precise and homogeneous structures and chemistry. This facilitates the mechanistic understanding of working catalysts and their subsequent optimization through interrogating reactive and functional interfaces by operando spectroscopy. The thin film catalysts studied here were synthesized with the objective of designing the interface structure of performance catalysts and closing the material gap between model and real-world powder catalysts while minimizing the use of noble metals. Its unique flat and densely packed structure (LCC) enables to achieve a homogeneous high density of surface active sites, minimizing the content of material present in the “bulk” or subsurface of the active catalysts with benefical effects on the selelctivity of the catalyzed reaction.
This effort is detailed in a study published in Nature Communications, entitled "Rationally Designed Laterally-Condensed-Catalysts Deliver Robust Activity and Selectivity for Ethylene Production in Acetylene Hydrogenation." The study is part of the CatLab Project, a collaboration prominently involving the Fritz Haber Institute of the Max Planck Society (FHI), the Helmholtz-Zentrum Berlin für Materialien und Energie and the Max Planck Institute for Chemical Energy Conversion. The CatLab Project is funded by Federal Ministry of Education and Research (BMBF).
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