Title :

Exploring the formation of gold/silver nanoalloys with gas-phase synthesis and machine-learning assisted simulations

Author(s) :

Gromoff, Quentin [Auteur]
Centre d'élaboration de matériaux et d'études structurales [CEMES]
Benzo, Patrizio [Auteur]
Centre d'élaboration de matériaux et d'études structurales [CEMES]
Saidi, Wissam A. [Auteur]
University of Pittsburgh [PITT]
Andolina, Christopher M. [Auteur]
University of Pittsburgh [PITT]
Casanove, Marie-José [Auteur]
Centre d'élaboration de matériaux et d'études structurales [CEMES]
Hungria, Teresa [Auteur]
Centre de microcaractérisation Raimond Castaing [Centre Castaing]
Barre, Sophie [Auteur]
Centre d'élaboration de matériaux et d'études structurales [CEMES]
Benoit, Magali [Auteur]
Centre d'élaboration de matériaux et d'études structurales [CEMES]
Lam, Julien [Auteur]
Unité Matériaux et Transformations (UMET) - UMR 8207

Journal title :

Nanoscale

Abbreviated title :

Nanoscale

Volume number :

16

Pages :

384-393

Publisher :

Royal Society of Chemistry (RSC)

Publication date :

2023-11-18

ISSN :

2040-3372

HAL domain(s) :

Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Planète et Univers [physics]/Sciences de la Terre

English abstract : [en]

While nanoalloys are of paramount scientific and practical interest, the main processes leading to their formation are still poorly understood. Key structural features in the alloy systems, including the crystal phase, ...
Show more >While nanoalloys are of paramount scientific and practical interest, the main processes leading to their formation are still poorly understood. Key structural features in the alloy systems, including the crystal phase, chemical ordering, and morphology, are challenging to control at the nanoscale, making it difficult to extend their use to industrial applications. In this contribution, we focus on the gold/silver system that has two of the most prevalent noble metals and combine experiments with simulations to uncover the formation mechanisms at the atomic level. Nanoparticles were produced using a state-of-the-art inert-gas aggregation source and analyzed using transmission electron microscopy and energy-dispersive X-ray spectroscopy. Machine-learning-assisted molecular dynamics simulations were employed to model the crystallization process from liquid droplets to nanocrystals. Our study finds a preponderance of nanoparticles with five-fold symmetric morphology, including icosahedra and decahedra which is consistent with previous results on mono-metallic nanoparticles. However, we observed that gold atoms, rather than silver atoms, segregate at the surface of the obtained nanoparticles for all the considered alloy compositions. These segregation tendencies are in contrast to previous studies and have consequences on the crystallization dynamics and the subsequent crystal ordering. We finally showed that the underpinning of this surprising segregation dynamics is due to charge transfer and electrostatic interactions rather than surface energy considerations.Show less >

Language :

Anglais

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS
INRAE
ENSCL

Collections :

• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Plasticité

Submission date :

2023-12-21T07:42:16Z
2023-12-22T10:14:54Z