Dynamic structural changes of ensemble and single supported Pt particles during ammonia oxidation
Year: 2025
Type: article
Abstract: Platinum and its alloys remains the state-of-the-art catalysts for selective nitric oxide production via ammonia oxidation.Yet improving efficiency, selectivity, and stability is a century-old challenge. Here, we combine operando surface X-ray diffraction, Bragg coherent diffraction imaging, and mass spectrometry to investigate structural dynamics of ensemble and single alpha-Al2O3-supported Pt crystalline particles under realistic reaction conditions. We identify distinct strain and morphology responses between particle types: large and elongated particles exhibit annealing-induced misfit strain and a stable morphology during the reaction, while smaller, round, and low-strain particles display surface roughening and defect evolution at 400 C, coinciding with enhanced NO selectivity. Notably, NH3 exposure at 600 C reverses facet strain.These findings highlight the critical role of nanoscale strain and morphology in catalyst performance and demonstrate the power of multi-techniques operando approaches to guide the design of next-generation catalytic materials.
Institutions: Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Synchrotron SOLEIL, CEA Grenoble, Institut de Recherche Interdisciplinaire de Grenoble, European Synchrotron Radiation Facility, Université Paris Cité, Laboratoire Matériaux et Phénomènes Quantiques, Centre National de la Recherche Scientifique, Université de Toulon, Aix-Marseille Université, Institut des Matériaux, de Microélectronique et des Nanosciences de Provence, Technion – Israel Institute of Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,950
Award: G588003148
OpenAlex ID: W4415215995