The Haber Bosch Catalyst from Solid state Chemistry to Mesotechnology
Abstract Ammonia is industrially synthesized over multi‐promoted Fe‐based catalysts for more than a century. Although ammonia synthesis reflects a prototypical catalytic reaction, rational catalyst design is still impossible as the full structural complexity of this catalyst system often referred to as ammonia iron and its structural entanglement is barely understood. Here, the mesoscopic structure of a technical, multi‐promoted ammonia synthesis catalyst is uncovered using a scale‐bridging electron microscopy approach complemented by X‐ray diffraction and spectroscopy to explore the structural integrity of ammonia iron. Amorphous contributions and structures of the melilite type and tricalcium aluminate as additional phases are identified. Furthermore, the understanding of the ammonia iron family by unveiling the role of the platelet‐Fe perimeter, framework Fe, thin film Fe, and refractory Fe is extended. Their interconnectedness is highlighted, suggesting that each component has to be present to fulfill a specific task. The study demonstrates that catalysis science can only proceed if it openly explores the full complexity of catalytic systems.
Authors
- Robert Schloegl (ORCID: https://orcid.org/0000-0002-5163-1051)
- René Eckert (ORCID: https://orcid.org/0000-0001-8644-163X)
- Wulyu Jiang (ORCID: https://orcid.org/0000-0003-2258-8688)
- David Kordus (ORCID: https://orcid.org/0000-0002-9481-2194)
- Kassiogé Dembélé (ORCID: https://orcid.org/0000-0001-5630-0414)
- Gregor Koch (ORCID: https://orcid.org/0000-0002-4091-7003)
- Thomas Lunkenbein (ORCID: https://orcid.org/0000-0002-8957-4216)
- Leonardo Díaz (ORCID: https://orcid.org/0000-0001-5027-8543)
- Janis Timoshenko (ORCID: https://orcid.org/0000-0003-2963-3912)
- Holger Ruland (ORCID: https://orcid.org/0000-0001-5530-1458)
- Maxime Boniface
- Raoul Blume (ORCID: https://orcid.org/0009-0006-4362-339X)
- Stephan J. Reitmeier
- Beatriz Roldán Cuenya (ORCID: https://orcid.org/0000-0002-8025-307X)
- Jan Folke (ORCID: https://orcid.org/0000-0003-2032-7548)
- Frank Girgsdies (ORCID: https://orcid.org/0000-0002-0994-0686)
- Adnan Hammud (ORCID: https://orcid.org/0000-0001-5580-7985)
- Jihao Wang (ORCID: https://orcid.org/0000-0003-3473-5980)
- Axel Knop‐Gericke (ORCID: https://orcid.org/0009-0008-1149-4102)
- Andreas Reitzmann
- Zahra Gheisari
Institutions
- Fritz Haber Institute of the Max Planck Society (DE)
- Clariant (Germany) (DE)
- Max Planck Institute for Chemical Energy Conversion (DE)
Publication Details
- Journal
- Advanced Energy Materials
- Published
- 2025-06-19
- DOI
- https://doi.org/10.1002/aenm.202500159
- Citations
- 3
- Primary Topic
- Ammonia Synthesis and Nitrogen Reduction
- Type
- article
- Field-Weighted Citation Impact
- 1.17
Funders
- Deutsche Forschungsgemeinschaft
- Bundesministerium für Bildung und Forschung