In Situ Strain Evolution on Pt Nanoparticles during Hydrogen Peroxide Decomposition.
Nano Lett
; 20(12): 8541-8548, 2020 Dec 09.
Article
em En
| MEDLINE
| ID: mdl-33174748
ABSTRACT
Fundamental understanding of structural changes during catalytic reactions is crucial to understanding the underlying mechanisms and optimizing efficiencies. Surface energy and related catalytic mechanisms are widely studied. However, the catalyst lattice deformation induced by catalytic processes is not well understood. Here, we study the strain in an individual platinum (Pt) nanoparticle (NP) using Bragg coherent diffraction imaging under in situ oxidation and reduction reactions. When Pt NPs are exposed to H2O2, a typical oxidizer and an intermediate during the oxygen reduction reaction process, alternating overall strain distribution near the surface and inside the NP is observed at the (111) Bragg reflection. In contrast, relatively insignificant changes appear in the (200) reflection. Density functional theory calculations are employed to rationalize the anisotropic lattice strain in terms of induced stress by H2O2 adsorption and decomposition on the Pt NP surface. Our study provides deeper insight into the activity-structure relationship in this system.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Nano Lett
Ano de publicação:
2020
Tipo de documento:
Article