Coalescence-induced crystallisation wave in Pd nanoparticles

Panagiotis Grammatikopoulos; Cathal Cassidy; Vidyadhar Singh; Mukhles Sowwan

doi:10.1038/srep05779

Coalescence-induced crystallisation wave in Pd nanoparticles

Panagiotis Grammatikopoulos^*, Cathal Cassidy, Vidyadhar Singh, Mukhles Sowwan

^*Corresponding author for this work

Research output: Contribution to journal › Article › peer-review

73 Scopus citations

Abstract

Palladium nanoparticles offer an attractive alternative to bulk palladium for catalysis, hydrogen storage and gas sensing applications. Their performance depends strongly on surface structure; therefore, nanoparticle coalescence can play an important role, as it determines the resultant structure of the active sites where reactions (e.g. catalysis) actually take place, i.e. facets, edges, vertices or protrusions. With this in mind, we performed classical molecular dynamics (MD) simulations and magnetron-sputtering inert gas condensation depositions of palladium nanoparticles, supported by high-resolution transmission electron microscopy (HRTEM), to study the mechanisms that govern their coalescence. Surface energy minimisation drove the interactions initially, leading to the formation of an interface/neck, as expected. Intriguingly, at a later stage, atomic rearrangements triggered a crystallisation wave propagating through the amorphous nanoparticles, leading to mono- or polycrystalline fcc structures. In the case of crystalline nanoparticles, almost-epitaxial alignment occurred and the formation of twins and surface protrusions were observed.

Original language	English
Article number	5779
Journal	Scientific Reports
Volume	4
DOIs	https://doi.org/10.1038/srep05779
State	Published - 1 Apr 2014
Externally published	Yes

Access to Document

10.1038/srep05779

Cite this

@article{b3bdc8d55d5a4240869c2f2058967dd9,

title = "Coalescence-induced crystallisation wave in Pd nanoparticles",

abstract = "Palladium nanoparticles offer an attractive alternative to bulk palladium for catalysis, hydrogen storage and gas sensing applications. Their performance depends strongly on surface structure; therefore, nanoparticle coalescence can play an important role, as it determines the resultant structure of the active sites where reactions (e.g. catalysis) actually take place, i.e. facets, edges, vertices or protrusions. With this in mind, we performed classical molecular dynamics (MD) simulations and magnetron-sputtering inert gas condensation depositions of palladium nanoparticles, supported by high-resolution transmission electron microscopy (HRTEM), to study the mechanisms that govern their coalescence. Surface energy minimisation drove the interactions initially, leading to the formation of an interface/neck, as expected. Intriguingly, at a later stage, atomic rearrangements triggered a crystallisation wave propagating through the amorphous nanoparticles, leading to mono- or polycrystalline fcc structures. In the case of crystalline nanoparticles, almost-epitaxial alignment occurred and the formation of twins and surface protrusions were observed.",

author = "Panagiotis Grammatikopoulos and Cathal Cassidy and Vidyadhar Singh and Mukhles Sowwan",

year = "2014",

month = apr,

day = "1",

doi = "10.1038/srep05779",

language = "英语",

volume = "4",

journal = "Scientific Reports",

issn = "2045-2322",

publisher = "Nature Publishing Group",

}

TY - JOUR

T1 - Coalescence-induced crystallisation wave in Pd nanoparticles

AU - Grammatikopoulos, Panagiotis

AU - Cassidy, Cathal

AU - Singh, Vidyadhar

AU - Sowwan, Mukhles

PY - 2014/4/1

Y1 - 2014/4/1

N2 - Palladium nanoparticles offer an attractive alternative to bulk palladium for catalysis, hydrogen storage and gas sensing applications. Their performance depends strongly on surface structure; therefore, nanoparticle coalescence can play an important role, as it determines the resultant structure of the active sites where reactions (e.g. catalysis) actually take place, i.e. facets, edges, vertices or protrusions. With this in mind, we performed classical molecular dynamics (MD) simulations and magnetron-sputtering inert gas condensation depositions of palladium nanoparticles, supported by high-resolution transmission electron microscopy (HRTEM), to study the mechanisms that govern their coalescence. Surface energy minimisation drove the interactions initially, leading to the formation of an interface/neck, as expected. Intriguingly, at a later stage, atomic rearrangements triggered a crystallisation wave propagating through the amorphous nanoparticles, leading to mono- or polycrystalline fcc structures. In the case of crystalline nanoparticles, almost-epitaxial alignment occurred and the formation of twins and surface protrusions were observed.

AB - Palladium nanoparticles offer an attractive alternative to bulk palladium for catalysis, hydrogen storage and gas sensing applications. Their performance depends strongly on surface structure; therefore, nanoparticle coalescence can play an important role, as it determines the resultant structure of the active sites where reactions (e.g. catalysis) actually take place, i.e. facets, edges, vertices or protrusions. With this in mind, we performed classical molecular dynamics (MD) simulations and magnetron-sputtering inert gas condensation depositions of palladium nanoparticles, supported by high-resolution transmission electron microscopy (HRTEM), to study the mechanisms that govern their coalescence. Surface energy minimisation drove the interactions initially, leading to the formation of an interface/neck, as expected. Intriguingly, at a later stage, atomic rearrangements triggered a crystallisation wave propagating through the amorphous nanoparticles, leading to mono- or polycrystalline fcc structures. In the case of crystalline nanoparticles, almost-epitaxial alignment occurred and the formation of twins and surface protrusions were observed.

UR - http://www.scopus.com/inward/record.url?scp=84919637372&partnerID=8YFLogxK

U2 - 10.1038/srep05779

DO - 10.1038/srep05779

M3 - 文章

AN - SCOPUS:84919637372

SN - 2045-2322

VL - 4

JO - Scientific Reports

JF - Scientific Reports

M1 - 5779

ER -

Coalescence-induced crystallisation wave in Pd nanoparticles

Abstract

Access to Document

Other files and links

Fingerprint

Cite this