Al Organization in the SSZ-13 Zeolite. Al Distribution and Extraframework Sites of Divalent Cations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388955%3A_____%2F19%3A00503931" target="_blank" >RIV/61388955:_____/19:00503931 - isvavai.cz</a>

Výsledek na webu

<a href="http://hdl.handle.net/11104/0295697" target="_blank" >http://hdl.handle.net/11104/0295697</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jpcc.8b07343" target="_blank" >10.1021/acs.jpcc.8b07343</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Al Organization in the SSZ-13 Zeolite. Al Distribution and Extraframework Sites of Divalent Cations

Popis výsledku v původním jazyce

SSZ-13 is a Si-rich (Si/Al > 5) small pore zeolite (chabazite topology) important for both acid and redox catalysis. Using a sample with Si/Al = 12, a new procedure involving 27Al (3Q) MAS NMR spectroscopy and extensive periodic DFT calculations with molecular dynamics, in addition to the standard methods based on bare Co(II) cations as probes monitored by FTIR spectroscopy and UV-vis spectroscopy, was employed. The placement of the Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al sequences in the zeolite framework was determined (Al-O-Si-O-Al sequences are absent). 54% of the framework Al atoms correspond to Al-O-(Si-O)3-Al sequences which cannot form cationic sites for bare divalent cations but are able to accommodate divalent Co(II) hexaaqua complexes. The corresponding Al-O-(Si-O)3-Al sequence is located in two double 6-ring cages with one Al located in the 4-ring connecting two double 6-ring units. Our study also reveals that 35% of the framework Al atoms can accommodate neither divalent Co(II) hexaaqua complexes nor bare divalent cations. Furthermore, the siting of the Al atoms of the Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al sequences forming four cationic sites for divalent cations located in the 6-ring (Al-O-(Si-O)2-Al), 8-ring (Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al), and double 6-ring (Al-O-(Si-O)2-Al) was determined. These Al atoms correspond to a minority of the Al framework atoms.

Název v anglickém jazyce

Al Organization in the SSZ-13 Zeolite. Al Distribution and Extraframework Sites of Divalent Cations

Popis výsledku anglicky

SSZ-13 is a Si-rich (Si/Al > 5) small pore zeolite (chabazite topology) important for both acid and redox catalysis. Using a sample with Si/Al = 12, a new procedure involving 27Al (3Q) MAS NMR spectroscopy and extensive periodic DFT calculations with molecular dynamics, in addition to the standard methods based on bare Co(II) cations as probes monitored by FTIR spectroscopy and UV-vis spectroscopy, was employed. The placement of the Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al sequences in the zeolite framework was determined (Al-O-Si-O-Al sequences are absent). 54% of the framework Al atoms correspond to Al-O-(Si-O)3-Al sequences which cannot form cationic sites for bare divalent cations but are able to accommodate divalent Co(II) hexaaqua complexes. The corresponding Al-O-(Si-O)3-Al sequence is located in two double 6-ring cages with one Al located in the 4-ring connecting two double 6-ring units. Our study also reveals that 35% of the framework Al atoms can accommodate neither divalent Co(II) hexaaqua complexes nor bare divalent cations. Furthermore, the siting of the Al atoms of the Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al sequences forming four cationic sites for divalent cations located in the 6-ring (Al-O-(Si-O)2-Al), 8-ring (Al-O-(Si-O)2-Al and Al-O-(Si-O)3-Al), and double 6-ring (Al-O-(Si-O)2-Al) was determined. These Al atoms correspond to a minority of the Al framework atoms.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

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

2019

Kód důvěrnosti údajů

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

Název periodika

Journal of Physical Chemistry C

ISSN

1932-7447

e-ISSN

—

Svazek periodika

123

Číslo periodika v rámci svazku

13

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

20

Strana od-do

7968-7987

Kód UT WoS článku

000463844500046

EID výsledku v databázi Scopus

2-s2.0-85056707231