Migration of zeolite-encapsulated Pt and Au under reducing environments

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F22%3A10450578" target="_blank" >RIV/00216208:11310/22:10450578 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=mc3UmMODMK" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=mc3UmMODMK</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d1cy02270a" target="_blank" >10.1039/d1cy02270a</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Migration of zeolite-encapsulated Pt and Au under reducing environments

Popis výsledku v původním jazyce

The encapsulation of noble metal atoms into zeolites is a promising route to generate controlled size distributions of stable metal catalysts. Pinning of single metal atoms to particular binding sites represents the optimal atom-efficiency and is a desirous outcome, despite the propensity of metal clusters to sinter. Currently, sintering resistance of noble metals in siliceous and high-silica frameworks is incompletely understood, while the role of influencing factors such as adsorbates and metal element identity, have not been ascertained. Here, we investigate the nature of metal-zeolite interactions, via density functional global structure optimisation and kinetic Monte Carlo simulations of the binding and migration of Pt and Au in a siliceous zeolite with framework topology LTA. We show that strong binding of Pt atoms to the framework severely hinders migration, even in the absence of framework heteroatoms, while Au diffuses freely through the pore. Reducing agents CO and H(2) change the preferred binding site of Pt and flatten the potential energy surface, which reduces migration barriers and thereby promotes particle growth. PtCO is found to represent a compromise between strongly framework-bound Pt(1), and bulky, volatile Pt(CO)(x) clusters, exhibiting fast diffusion. This work provides an atomistic picture of single metal atom kinetics inside high-silica zeolites, which represent a fundamental basis for understanding nano-catalyst deactivation.

Název v anglickém jazyce

Migration of zeolite-encapsulated Pt and Au under reducing environments

Popis výsledku anglicky

The encapsulation of noble metal atoms into zeolites is a promising route to generate controlled size distributions of stable metal catalysts. Pinning of single metal atoms to particular binding sites represents the optimal atom-efficiency and is a desirous outcome, despite the propensity of metal clusters to sinter. Currently, sintering resistance of noble metals in siliceous and high-silica frameworks is incompletely understood, while the role of influencing factors such as adsorbates and metal element identity, have not been ascertained. Here, we investigate the nature of metal-zeolite interactions, via density functional global structure optimisation and kinetic Monte Carlo simulations of the binding and migration of Pt and Au in a siliceous zeolite with framework topology LTA. We show that strong binding of Pt atoms to the framework severely hinders migration, even in the absence of framework heteroatoms, while Au diffuses freely through the pore. Reducing agents CO and H(2) change the preferred binding site of Pt and flatten the potential energy surface, which reduces migration barriers and thereby promotes particle growth. PtCO is found to represent a compromise between strongly framework-bound Pt(1), and bulky, volatile Pt(CO)(x) clusters, exhibiting fast diffusion. This work provides an atomistic picture of single metal atom kinetics inside high-silica zeolites, which represent a fundamental basis for understanding nano-catalyst deactivation.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/GJ20-26767Y" target="_blank" >GJ20-26767Y: Stabilita kovových klastrů v zeolitech: mikrokinetický model založený na ab initio a experimentálních datech</a><br>

Návaznosti

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

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

Catalysis: Science and Technology

ISSN

2044-4753

e-ISSN

2044-4761

Svazek periodika

12

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

12

Strana od-do

1598-1609

Kód UT WoS článku

000748367100001

EID výsledku v databázi Scopus

2-s2.0-85136164289