Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes

Handle URI:
http://hdl.handle.net/10754/626185
Title:
Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes
Authors:
Sun, Xiaohui; Olivos-Suarez, Alma I.; Osadchii, Dmitrii; Romero, Maria Jose Valero; Kapteijn, Freek; Gascon, Jorge
Abstract:
A supported cobalt catalyst with atomically dispersed Co-Nx sites (3.5 wt% Co) in a mesoporous N-doped carbon matrix (named Co@mesoNC) is synthesized by hydrolysis of tetramethyl orthosilicate (TMOS) in a Zn/Co bimetallic zeolitic imidazolate framework (BIMZIF(Co,Zn)), followed by high-temperature pyrolysis and SiO2 leaching. A combination of TEM, XRD XPS and X-ray absorption spectroscopy studies confirm the absence of cobalt nanoparticles and indicate that these highly dispersed cobalt species are present in the form of Co-Nx. The exclusive formation of Co-Nx sites in the carbon matrix is attributed to the presence of a large amount of Zn and N in the BIMZIF precursor together with the presence of SiO2 in the pore space of this framework, extending the initial spatial distance between cobalt atoms and thereby impeding their agglomeration. The presence of SiO2 during high-temperature pyrolysis is proven crucial to create mesoporosity and a high BET area and pore volume in the N-doped carbon support (1780 m2 g−1, 1.54 cm3 g−1). This heterogeneous Co@mesoNC catalyst displays high activity and selectivity (>99%) for the selective hydrogenation of nitrobenzene to aniline at mild conditions (0.5–3 MPa, 343–383 K). When more challenging substrates (functionalized nitroarenes) are hydrogenated, the catalyst Co@mesoNC displays an excellent chemoselectivity to the corresponding substituted anilines.The presence of mesoporosity improves mass transport of reactants and/or products and the accessibility of the active Co-Nx sites, and greatly reduces deactivation due to fouling.
KAUST Department:
KAUST Catalysis Center (KCC)
Citation:
Sun X, Olivos-Suarez AI, Osadchii D, Romero MJV, Kapteijn F, et al. (2018) Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes. Journal of Catalysis 357: 20–28. Available: http://dx.doi.org/10.1016/j.jcat.2017.10.030.
Publisher:
Elsevier BV
Journal:
Journal of Catalysis
Issue Date:
20-Nov-2017
DOI:
10.1016/j.jcat.2017.10.030
Type:
Article
ISSN:
0021-9517
Sponsors:
We thank for the support from the Dutch-Belgian program for access to the BM26A in ESRF, Grenoble. We thank A. Dikhtiarenko for help in the design of the graphical abstract. Xiaohui Sun acknowledges financial support from China Scholarship Council (CSC).
Additional Links:
http://www.sciencedirect.com/science/article/pii/S0021951717303901
Appears in Collections:
Articles; KAUST Catalysis Center (KCC)

Full metadata record

DC FieldValue Language
dc.contributor.authorSun, Xiaohuien
dc.contributor.authorOlivos-Suarez, Alma I.en
dc.contributor.authorOsadchii, Dmitriien
dc.contributor.authorRomero, Maria Jose Valeroen
dc.contributor.authorKapteijn, Freeken
dc.contributor.authorGascon, Jorgeen
dc.date.accessioned2017-11-21T11:18:54Z-
dc.date.available2017-11-21T11:18:54Z-
dc.date.issued2017-11-20en
dc.identifier.citationSun X, Olivos-Suarez AI, Osadchii D, Romero MJV, Kapteijn F, et al. (2018) Single cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenes. Journal of Catalysis 357: 20–28. Available: http://dx.doi.org/10.1016/j.jcat.2017.10.030.en
dc.identifier.issn0021-9517en
dc.identifier.doi10.1016/j.jcat.2017.10.030en
dc.identifier.urihttp://hdl.handle.net/10754/626185-
dc.description.abstractA supported cobalt catalyst with atomically dispersed Co-Nx sites (3.5 wt% Co) in a mesoporous N-doped carbon matrix (named Co@mesoNC) is synthesized by hydrolysis of tetramethyl orthosilicate (TMOS) in a Zn/Co bimetallic zeolitic imidazolate framework (BIMZIF(Co,Zn)), followed by high-temperature pyrolysis and SiO2 leaching. A combination of TEM, XRD XPS and X-ray absorption spectroscopy studies confirm the absence of cobalt nanoparticles and indicate that these highly dispersed cobalt species are present in the form of Co-Nx. The exclusive formation of Co-Nx sites in the carbon matrix is attributed to the presence of a large amount of Zn and N in the BIMZIF precursor together with the presence of SiO2 in the pore space of this framework, extending the initial spatial distance between cobalt atoms and thereby impeding their agglomeration. The presence of SiO2 during high-temperature pyrolysis is proven crucial to create mesoporosity and a high BET area and pore volume in the N-doped carbon support (1780 m2 g−1, 1.54 cm3 g−1). This heterogeneous Co@mesoNC catalyst displays high activity and selectivity (>99%) for the selective hydrogenation of nitrobenzene to aniline at mild conditions (0.5–3 MPa, 343–383 K). When more challenging substrates (functionalized nitroarenes) are hydrogenated, the catalyst Co@mesoNC displays an excellent chemoselectivity to the corresponding substituted anilines.The presence of mesoporosity improves mass transport of reactants and/or products and the accessibility of the active Co-Nx sites, and greatly reduces deactivation due to fouling.en
dc.description.sponsorshipWe thank for the support from the Dutch-Belgian program for access to the BM26A in ESRF, Grenoble. We thank A. Dikhtiarenko for help in the design of the graphical abstract. Xiaohui Sun acknowledges financial support from China Scholarship Council (CSC).en
dc.publisherElsevier BVen
dc.relation.urlhttp://www.sciencedirect.com/science/article/pii/S0021951717303901en
dc.rightsNOTICE: this is the author’s version of a work that was accepted for publication in Journal of Catalysis. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Catalysis, [, , (2017-11-20)] DOI: 10.1016/j.jcat.2017.10.030 . © 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/en
dc.subjectNitroareneen
dc.subjectHydrogenationen
dc.subjectCo single atomen
dc.subjectChemoselectivityen
dc.titleSingle cobalt sites in mesoporous N-doped carbon matrix for selective catalytic hydrogenation of nitroarenesen
dc.typeArticleen
dc.contributor.departmentKAUST Catalysis Center (KCC)en
dc.identifier.journalJournal of Catalysisen
dc.eprint.versionPost-printen
dc.contributor.institutionCatalysis Engineering, Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlandsen
kaust.authorOlivos-Suarez, Alma I.en
kaust.authorGascon, Jorgeen
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