Nature of the Surface Intermediates Formed from Methane on Cu-ZSM-5 Zeolite: A Combined Solid-State Nuclear Magnetic Resonance and Density Functional Theory Study Full article
| Journal |
The Journal of Physical Chemistry C
ISSN: 1932-7447 , E-ISSN: 1932-7455 |
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| Output data | Year: 2020, Volume: 124, Number: 11, Pages: 6242-6252 Pages count : 11 DOI: 10.1021/acs.jpcc.0c00311 | ||||||
| Tags | Chemical activation; Density functional theory; Methane; Methanol; Nuclear magnetic resonance spectroscopy; Zeolites | ||||||
| Authors |
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| Affiliations |
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Funding (2)
| 1 | Federal Agency for Scientific Organizations | 0303-2016-0003 |
| 2 | Russian Science Foundation | 18-73-00016 |
Abstract:
The intermediates formed upon the interaction of methane with Cu-modified ZSM-5 zeolites (Cu/H-ZSM-5) have been analyzed with solid-state NMR spectroscopy and DFT methods. Methane activation by Cu/H-ZSM-5 zeolites gives rise to three distinct surface methoxy-like species (-O-CH3) detected by 13C MAS NMR spectroscopy with specific chemical shifts in the range of 53-63 ppm. DFT calculations on representative cluster models of different sites potentially present in Cu/H-ZSM-5 have been used to assign these signals to (i) methanol adsorbed on two neighboring Cu sites (Cu-(HOCH3)-Cu, 62.6 ppm), (ii) methanol adsorbed on zeolite Brønsted acid sites (52.9 ppm), and (iii) lattice-bound methoxy groups (Si-O(CH3)-Al, 58.6). The formation of these methoxy-like intermediates depends on the Cu loading and, accordingly, the type of Cu species in the Cu/H-ZSM-5 zeolite. For the sample with low (0.1 wt %) Cu loading containing exclusively mononuclear isolated Cu species, only the intermediates ii and iii have been detected. The Cu-bound intermediate (i) is formed upon methane activation by multinuclear Cu sites featuring Cu-O-Cu bridging moieties present in the materials with relatively higher Cu loading (1.38 wt %). The presented results indicate that methane activation by Cu/H-ZSM-5 can be promoted by both mono- and multinuclear Cu species confined in the zeolite matrix. Copyright © 2020 American Chemical Society.
Cite:
Kolganov A.A.
, Gabrienko A.A.
, Yashnik S.A.
, Pidko E.A.
, Stepanov A.G.
Nature of the Surface Intermediates Formed from Methane on Cu-ZSM-5 Zeolite: A Combined Solid-State Nuclear Magnetic Resonance and Density Functional Theory Study
The Journal of Physical Chemistry C. 2020.
V.124. N11. P.6242-6252. DOI: 10.1021/acs.jpcc.0c00311
WOS
Scopus
РИНЦ
AN
OpenAlex
Nature of the Surface Intermediates Formed from Methane on Cu-ZSM-5 Zeolite: A Combined Solid-State Nuclear Magnetic Resonance and Density Functional Theory Study
The Journal of Physical Chemistry C. 2020.
V.124. N11. P.6242-6252. DOI: 10.1021/acs.jpcc.0c00311
WOS
Scopus
РИНЦ
AN
OpenAlex
Files:
Full text from publisher
Dates:
| Submitted: | Jan 13, 2020 |
| Accepted: | Feb 17, 2020 |
| Published online: | Feb 26, 2020 |
| Published print: | Mar 19, 2020 |
Identifiers:
| Web of science: | WOS:000526396000038 |
| Scopus: | 2-s2.0-85081694425 |
| Elibrary: | 43254052 |
| Chemical Abstracts: | 2020:385557 |
| OpenAlex: | W3007294050 |