Steering the formation of supported Pt-Sn nanoalloys by reactive metal-oxide interaction

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F16%3A10334334" target="_blank" >RIV/00216208:11320/16:10334334 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1039/c6ra18801j" target="_blank" >http://dx.doi.org/10.1039/c6ra18801j</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/c6ra18801j" target="_blank" >10.1039/c6ra18801j</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Steering the formation of supported Pt-Sn nanoalloys by reactive metal-oxide interaction

Popis výsledku v původním jazyce

The formation of a supported Pt-Sn nanoalloy upon reactive metal-oxide interaction between Pt nanoparticles and a Sn-CeO2 substrate has been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy in combination with density functional modeling. It was found that Pt deposition onto a Sn-CeO2 substrate triggers the reduction of Sn2+ cations yielding Pt-Sn nanoalloys at 300 K under ultra-high vacuum conditions. Three distinct stages of Pt-Sn nanoalloy formation were identified associated with the growth of (I) ultra-small monometallic Pt particles on a Sn-CeO2 substrate, (II) Pt-Sn nanoalloys on a Sn-CeO2 substrate, and (III) Pt-Sn nanoalloys on a stoichiometric CeO2 substrate. These findings suggest the existence of a critical size of monometallic Pt particles above which the formation of a Pt-Sn nanoalloy becomes favorable. In this respect, density functional modeling revealed a strong dependence of the formation energy of the PtxSn nanoalloy on the size of the Pt particle. Additionally, the thermodynamically favorable bulk and surface Pt/Sn stoichiometries were identified as two parameters that determine the composition of the supported Pt-Sn nanoalloys and limit the extraction of Sn2+ from the Sn-CeO2 substrate. Primarily, the formation of a bulk Pt3Sn alloy phase drives the growth of the Pt-Sn nanoalloy upon Pt deposition at 300 K. Upon annealing, Sn segregation on the surface of the Pt-Sn nanoalloy promotes further extraction of Sn2+ until the thermodynamically stable Pt/Sn concentration ratios of 3 for the bulk and approximately 1.6 for the surface are reached.

Název v anglickém jazyce

Steering the formation of supported Pt-Sn nanoalloys by reactive metal-oxide interaction

Popis výsledku anglicky

The formation of a supported Pt-Sn nanoalloy upon reactive metal-oxide interaction between Pt nanoparticles and a Sn-CeO2 substrate has been investigated by means of synchrotron radiation photoelectron spectroscopy and resonant photoemission spectroscopy in combination with density functional modeling. It was found that Pt deposition onto a Sn-CeO2 substrate triggers the reduction of Sn2+ cations yielding Pt-Sn nanoalloys at 300 K under ultra-high vacuum conditions. Three distinct stages of Pt-Sn nanoalloy formation were identified associated with the growth of (I) ultra-small monometallic Pt particles on a Sn-CeO2 substrate, (II) Pt-Sn nanoalloys on a Sn-CeO2 substrate, and (III) Pt-Sn nanoalloys on a stoichiometric CeO2 substrate. These findings suggest the existence of a critical size of monometallic Pt particles above which the formation of a Pt-Sn nanoalloy becomes favorable. In this respect, density functional modeling revealed a strong dependence of the formation energy of the PtxSn nanoalloy on the size of the Pt particle. Additionally, the thermodynamically favorable bulk and surface Pt/Sn stoichiometries were identified as two parameters that determine the composition of the supported Pt-Sn nanoalloys and limit the extraction of Sn2+ from the Sn-CeO2 substrate. Primarily, the formation of a bulk Pt3Sn alloy phase drives the growth of the Pt-Sn nanoalloy upon Pt deposition at 300 K. Upon annealing, Sn segregation on the surface of the Pt-Sn nanoalloy promotes further extraction of Sn2+ until the thermodynamically stable Pt/Sn concentration ratios of 3 for the bulk and approximately 1.6 for the surface are reached.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

BM - Fyzika pevných látek a magnetismus

OECD FORD obor

—

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

RSC Advances

ISSN

2046-2069

e-ISSN

—

Svazek periodika

6

Číslo periodika v rámci svazku

89

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

10

Strana od-do

85688-85697

Kód UT WoS článku

000384322700002

EID výsledku v databázi Scopus

2-s2.0-84987842772