How to manipulate nanoparticle morphology with vacancies

Ilia Smirnov; Zbigniew Kaszkur; Riccardo Ferrando

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arXiv · 2409.01254

How to manipulate nanoparticle morphology with vacancies

Ilia Smirnov·Zbigniew Kaszkur·Riccardo Ferrando

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Abstract

Stacking defects in noble metal nanoparticles significantly impact their optical, catalytic, and electrical properties. While some mechanisms behind their formation have been studied, the ability to deliberately manipulate nanoparticle bulk morphology remains largely unexplored. In this work, we introduce a pioneering mechanism - vacancy-driven twinning - that enables the transformation of face-centered cubic (fcc) gold into locally hexagonal close-packed (hcp) structures. This innovative approach, demonstrated through computational simulations, facilitates the creation of realistic , randomly multi-twinned nanoparticle models. By employing a recently developed multidomain X-ray diffraction method (MDXRD), we quantitatively assess the degree of twinning. It is a crucial step in transferring theoretical studies into practical applications. Our work aims to develop tools for modifying and controlling the bulk structure of fcc nanoparticles

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Ilia Smirnov, Zbigniew Kaszkur, Riccardo Ferrando. 2024-09-02. How to manipulate nanoparticle morphology with vacancies. https://arxiv.org/abs/2409.01254

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