Coherent X-ray Diffraction Imaging of a Twinned PtRh Catalyst Nanoparticle under Operando Conditions.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40559514.
- Also identified by DOI 10.1021/acsnano.4c15457 and PMC identifier 12257639.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
We performed operando Bragg coherent X-ray diffraction imaging under CO oxidation, as well as oxidizing conditions on a precharacterized single PtRh nanoparticle. We found that this (111) oriented particle with truncated octahedral shape is twinned with a Σ3 twin boundary parallel to the SrTiO<sub>3</sub> (001) support, at the height of the nanoparticle edges. We observed that the average strain at the twin boundary is higher under CO oxidation conditions compared to pure CO or O<sub>2</sub>. In addition, we observed that two new facets were forming during the oxidizing/reducing cycles. Furthermore, we observed mixed edge/screw dislocations at the twin boundary, but only where the {111} side facets meet. Inducing such dislocations changes the local strain and the atomic structure of the nanoparticles, which may create more active sites close to the nanoparticle edges.