UZH-Logo

Maintenance Infos

Microwave-hydrothermal synthesis and characterization of nanostructured copper substituted ZnM2O4 (M = Al, Ga) spinels as precursors for thermally stable Cu catalysts


Conrad, F; Massue, C; Kuehl, S; Kunkes, E; Girgsdies, F; Kasatkin, I; Zhang, B; Friedrich, M; Luo, Y; Armbruester, M; Patzke, G R; Behrens, M (2012). Microwave-hydrothermal synthesis and characterization of nanostructured copper substituted ZnM2O4 (M = Al, Ga) spinels as precursors for thermally stable Cu catalysts. Nanoscale, 4(6):2018-2028.

Abstract

Nanostructured CuxZn1-xAl2O4 with a Cu : Zn ratio of 1/4 : 3/4 has been prepared by a microwave-assisted hydrothermal synthesis at 150 degrees C and used as a precursor for Cu/ZnO/Al2O3-based catalysts. The spinel nanoparticles exhibit an average size of approximately 5 nm and a high specific surface area (above 250 m(2) g(-1)). Cu nanoparticles of an average size of 3.3 nm can be formed by reduction of the spinel precursor in hydrogen and the accessible metallic Cu(0) surface area of the reduced catalyst was 8 m(2) g(-1). The catalytic performance of the material in CO2 hydrogenation and methanol steam reforming was compared with conventionally prepared Cu/ZnO/Al2O3 reference catalysts. The observed lower performance of the spinel-based samples is attributed to a lack of synergetic interaction of the Cu nanoparticles with ZnO due to the incorporation of Zn2+ in the stable spinel lattice. Despite its lower performance, however, the nanostructured nature of the spinel catalyst was stable after thermal treatment up to 500 degrees C in contrast to other Cu-based catalysts. Furthermore, a large fraction of the re-oxidized copper migrates back into the spinel upon calcination of the reduced catalyst, thereby enabling a regeneration of sintered catalysts after prolonged usage at high temperatures. Similarly prepared samples with Ga instead of Al exhibit a more crystalline catalyst with a spinel particle size around 20 nm. The slightly decreased Cu(0) surface area of 3.2 m(2) g(-1) due to less copper incorporation is not a significant drawback for the methanol steam reforming.

Nanostructured CuxZn1-xAl2O4 with a Cu : Zn ratio of 1/4 : 3/4 has been prepared by a microwave-assisted hydrothermal synthesis at 150 degrees C and used as a precursor for Cu/ZnO/Al2O3-based catalysts. The spinel nanoparticles exhibit an average size of approximately 5 nm and a high specific surface area (above 250 m(2) g(-1)). Cu nanoparticles of an average size of 3.3 nm can be formed by reduction of the spinel precursor in hydrogen and the accessible metallic Cu(0) surface area of the reduced catalyst was 8 m(2) g(-1). The catalytic performance of the material in CO2 hydrogenation and methanol steam reforming was compared with conventionally prepared Cu/ZnO/Al2O3 reference catalysts. The observed lower performance of the spinel-based samples is attributed to a lack of synergetic interaction of the Cu nanoparticles with ZnO due to the incorporation of Zn2+ in the stable spinel lattice. Despite its lower performance, however, the nanostructured nature of the spinel catalyst was stable after thermal treatment up to 500 degrees C in contrast to other Cu-based catalysts. Furthermore, a large fraction of the re-oxidized copper migrates back into the spinel upon calcination of the reduced catalyst, thereby enabling a regeneration of sintered catalysts after prolonged usage at high temperatures. Similarly prepared samples with Ga instead of Al exhibit a more crystalline catalyst with a spinel particle size around 20 nm. The slightly decreased Cu(0) surface area of 3.2 m(2) g(-1) due to less copper incorporation is not a significant drawback for the methanol steam reforming.

Citations

9 citations in Web of Science®
11 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

3 downloads since deposited on 05 Mar 2013
0 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Department of Chemistry
Dewey Decimal Classification:540 Chemistry
Language:English
Date:2012
Deposited On:05 Mar 2013 12:47
Last Modified:05 Apr 2016 16:36
Publisher:RSC Publishing
ISSN:2040-3364
Additional Information:Persons who receive the PDF must not make it further available or distribute it.
Publisher DOI:https://doi.org/10.1039/C2NR11804A
Permanent URL: https://doi.org/10.5167/uzh-75244

Download

[img]
Content: Published Version
Filetype: PDF - Registered users only
Size: 1MB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations