Direct atomic-scale investigation of the coarsening mechanisms of exsolved catalytic Ni nanoparticles
Exsolution-active catalysts allow for the formation of highly active metallic nanoparticles, yet recent work has shown that their long-term thermal stability remains a challenge. In this work, the dynamics of exsolved Ni nanoparticles are probed in-situ with atomically resolved secondary electron imaging with environmental scanning transmission electron microscopy. Pre-characterization shows embedded NiO<sub>x</sub> nanostructures within the parent oxide. Subsequent in-situ exsolution demonstrates that two populations of exsolved particles form with distinct metal-support interactions and coarsening behaviors. Nanoparticles which precipitate above embedded nanostructures are observed to be more stable, and are prevented from migrating on the surface of the support. Nanoparticle migration which fits random-walk kinetics is observed, and particle behavior is shown to be analogous to a classical wetting model. Additionally, DFT calculations indicate that particle motion is facilitated by the support oxide. Ostwald ripening processes are visualized simultaneously to migration, including particle redissolution and particle ripening.
Authors
- Joachim Mayer (ORCID: https://orcid.org/0000-0003-3292-5342)
- Ivar E. Reimanis (ORCID: https://orcid.org/0000-0001-7401-3275)
- Moritz L. Weber (ORCID: https://orcid.org/0000-0003-1105-2474)
- Olivier Guillon (ORCID: https://orcid.org/0000-0003-4831-5725)
- Ansgar Meise (ORCID: https://orcid.org/0009-0004-1781-9490)
- Felix Gunkel (ORCID: https://orcid.org/0000-0003-1178-9986)
- Marc Heggen (ORCID: https://orcid.org/0000-0002-2646-0078)
- Tobias Binninger (ORCID: https://orcid.org/0000-0001-9058-0501)
- Conor Jason Price (ORCID: https://orcid.org/0000-0002-1430-3294)
- Regina Dittmann (ORCID: https://orcid.org/0000-0003-1886-1864)
- Piotr M. Kowalski (ORCID: https://orcid.org/0000-0001-6604-3458)
- Dylan Jennings (ORCID: https://orcid.org/0000-0002-5492-8571)
- Wolfgang Rheinheimer (ORCID: https://orcid.org/0000-0002-2906-4265)
- Moritz Kindelmann (ORCID: https://orcid.org/0000-0001-9676-2090)
- Pengfei Cao (ORCID: https://orcid.org/0000-0002-8360-4541)
- Hiroaki Matsumoto (ORCID: https://orcid.org/0000-0001-5096-1537)
Institutions
- University of Stuttgart (DE)
- Kyushu University (JP)
- Colorado School of Mines (US)
- Forschungszentrum Jülich (DE)
- Kyushu Institute of Technology (JP)
- Ernst Ruska Centre (DE)
- Stuttgart Technical University of Applied Sciences (DE)
- Hitachi (Japan) (JP)
- RWTH Aachen University (DE)
- Ruhr University Bochum (DE)
- Technical University of Denmark (DK)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-07-24
- DOI
- https://doi.org/10.1038/s41467-025-61971-z
- Citations
- 3
- Primary Topic
- Copper-based nanomaterials and applications
- Type
- article
- Field-Weighted Citation Impact
- 1.55
Funders
- Deutsche Forschungsgemeinschaft