Periodic structural changes in Pd nanoparticles during oscillatory CO oxidation reaction

• Published in: Nature communications Vol. 13; no. 1; p. 6176
• Main Authors: Ghosh, Tanmay, Arce-Ramos, Juan Manuel, Li, Wen-Qing, Yan, Hongwei, Chee, See Wee, Genest, Alexander, Mirsaidov, Utkur
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 19.10.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 147/143; 639/301/357/354; 639/638/77/887; 639/925/357/354; 639/925/930/12; Atomic structure; Carbon dioxide; Carbon monoxide; Catalysts; Catalytic activity; Environmental impact; High temperature; Humanities and Social Sciences; multidisciplinary; Nanoparticles; Oscillations; Oxidation; Palladium; Reactive environments; Reconstruction; Science; Science (multidisciplinary); Surface properties; Transmission electron microscopy
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-33304-x

Nanoparticle (NP) catalysts are ubiquitous in energy systems, chemical production, and reducing the environmental impact of many industrial processes. Under reactive environments, the availability of catalytically active sites on the NP surface is determined by its dynamic structure. However, atomic-scale insights into how a NP surface reconstructs under reaction conditions and the impact of the reconstruction on catalytic activity are still lacking. Using operando transmission electron microscopy, we show that Pd NPs exhibit periodic round–to–flat transitions altering their facets during CO oxidation reaction at atmospheric pressure and elevated temperatures. This restructuring causes spontaneous oscillations in the conversion of CO to CO 2 under constant reaction conditions. Our study reveals that the oscillatory behavior stems from the CO-adsorption-mediated periodic restructuring of the nanocatalysts between high-index-faceted round and low-index-faceted flat shapes. These atomic-scale insights into the dynamic surface properties of NPs under reactive conditions play an important role in the design of high-performance catalysts. Atomic-scale insights into how a nanoparticle surface reconstructs under reaction conditions and the impact of the reconstruction on catalytic activity are still lacking. Here the authors reveal that Pd nanocatalysts display oscillatory changes in both their structure and activity during CO oxidation using operando TEM.