1
|
Skoda D, Zhu R, Hanulikova B, Styskalik A, Vykoukal V, Machac P, Simonikova L, Kuritka I, Poleunis C, Debecker DP, Román-Leshkov Y. Propylene Metathesis over Molybdenum Silicate Microspheres with Dispersed Active Sites. ACS Catal 2023; 13:12970-12982. [PMID: 37822857 PMCID: PMC10563125 DOI: 10.1021/acscatal.3c02045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/31/2023] [Indexed: 10/13/2023]
Abstract
In this work, we demonstrate that amorphous and porous molybdenum silicate microspheres are highly active catalysts for heterogeneous propylene metathesis. Homogeneous molybdenum silicate microspheres and aluminum-doped molybdenum silicate microspheres were synthesized via a nonaqueous condensation of a hybrid molybdenum biphenyldicarboxylate-based precursor solution with (3-aminopropyl)triethoxysilane. The as-prepared hybrid metallosilicate products were calcined at 500 °C to obtain amorphous and porous molybdenum silicate and aluminum-doped molybdenum silicate microspheres with highly dispersed molybdate species inserted into the silicate matrix. These catalysts contain mainly highly dispersed MoOx species, which possess high catalytic activity in heterogeneous propylene metathesis to ethylene and butene. Compared to conventional silica-supported MoOx catalysts prepared via incipient wetness impregnation (MoIWI), the microspheres with low Mo content (1.5-3.6 wt %) exhibited nearly 2 orders of magnitude higher steady-state propylene metathesis rates at 200 °C, approaching site time yields of 0.11 s-1.
Collapse
Affiliation(s)
- David Skoda
- Centre
of Polymer Systems, Tomas Bata University
in Zlin, tr. Tomase Bati 5678, Zlin CZ-76001, Czech Republic
| | - Ran Zhu
- Department
of Chemical Engineering, Massachusetts Institute
of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Barbora Hanulikova
- Centre
of Polymer Systems, Tomas Bata University
in Zlin, tr. Tomase Bati 5678, Zlin CZ-76001, Czech Republic
| | - Ales Styskalik
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska
2, Brno CZ-61137, Czech Republic
| | - Vit Vykoukal
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska
2, Brno CZ-61137, Czech Republic
- Central
European Institute of Technology, Masaryk
University, Kamenice
5, Brno CZ 62500, Czech Republic
| | - Petr Machac
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska
2, Brno CZ-61137, Czech Republic
| | - Lucie Simonikova
- Department
of Chemistry, Faculty of Science, Masaryk
University, Kotlarska
2, Brno CZ-61137, Czech Republic
| | - Ivo Kuritka
- Centre
of Polymer Systems, Tomas Bata University
in Zlin, tr. Tomase Bati 5678, Zlin CZ-76001, Czech Republic
| | - Claude Poleunis
- Institute
of Condensed Matter and Nanosciences (IMCN), Université catholique de Louvain (UCLouvain), Place Louis Pasteur 1, 1348 Louvain-la-Neuve, Belgium
| | - Damien P. Debecker
- Institute
of Condensed Matter and Nanosciences (IMCN), Université catholique de Louvain (UCLouvain), Place Louis Pasteur 1, 1348 Louvain-la-Neuve, Belgium
| | - Yuriy Román-Leshkov
- Department
of Chemical Engineering, Massachusetts Institute
of Technology (MIT), 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| |
Collapse
|
2
|
Liu Y, Agarwal A, Kratish Y, Marks TJ. Single-Site Carbon-Supported Metal-Oxo Complexes in Heterogeneous Catalysis: Structure, Reactivity, and Mechanism. Angew Chem Int Ed Engl 2023; 62:e202304221. [PMID: 37142561 DOI: 10.1002/anie.202304221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/28/2023] [Accepted: 05/02/2023] [Indexed: 05/06/2023]
Abstract
When early transition metal complexes are molecularly grafted onto catalyst supports, well-defined, surface-bound species are created, which are highly active and selective single-site heterogeneous catalysts (SSHCs) for diverse chemical transformations. In this minireview, we analyze and summarize a less conventional type of SSHC in which molybdenum dioxo species are grafted onto unusual carbon-unsaturated scaffolds, such as activated carbon, reduced graphene oxide, and carbon nanohorns. The choice of earth-abundant, low-toxicity, versatile metal constituents, and various carbon supports illustrates "catalyst by design" principles and yields insights into new catalytic systems of both academic and technological interest. Here, we summarize experimental and computational investigations of the bonding, electronic structure, reaction scope, and mechanistic pathways of these unusual catalysts.
Collapse
Affiliation(s)
- Yiqi Liu
- Department of Chemistry and the, Institute for Catalysis in Energy Processes (ICEP), 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Amol Agarwal
- Department of Material Science and Engineering and the, Institute for Catalysis in Energy Processes (ICEP), 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Yosi Kratish
- Department of Chemistry and the, Institute for Catalysis in Energy Processes (ICEP), 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Tobin J Marks
- Department of Chemistry and the, Institute for Catalysis in Energy Processes (ICEP), 2145 Sheridan Road, Evanston, IL 60208, USA
| |
Collapse
|
3
|
Berkson ZJ, Zhu R, Ehinger C, Lätsch L, Schmid SP, Nater D, Pollitt S, Safonova OV, Björgvinsdóttir S, Barnes AB, Román-Leshkov Y, Price GA, Sunley GJ, Copéret C. Active Site Descriptors from 95Mo NMR Signatures of Silica-Supported Mo-Based Olefin Metathesis Catalysts. J Am Chem Soc 2023. [PMID: 37256723 DOI: 10.1021/jacs.3c02201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The olefin metathesis activity of silica-supported molybdenum oxides depends strongly on metal loading and preparation conditions, indicating that the nature and/or amounts of the active sites vary across compositionally similar catalysts. This is illustrated by comparing Mo-based (pre)catalysts prepared by impregnation (2.5-15.6 wt % Mo) and a model material (2.3 wt % Mo) synthesized via surface organometallic chemistry (SOMC). Analyses of FTIR, UV-vis, and Mo K-edge X-ray absorption spectra show that these (pre)catalysts are composed predominantly of similar isolated Mo dioxo sites. However, they exhibit different reaction properties in both liquid and gas-phase olefin metathesis with the SOMC-derived catalyst outperforming a classical catalyst of a similar Mo loading by ×1.5-2.0. Notably, solid-state 95Mo NMR analyses leveraging state-of-the-art high-field (28.2 T) measurement conditions resolve four distinct surface Mo dioxo sites with distributions that depend on the (pre)catalyst preparation methods. The intensity of a specific deshielded 95Mo NMR signal, which is most prominent in the SOMC-derived catalyst, is linked to reducibility and catalytic activity. First-principles calculations show that 95Mo NMR parameters directly manifest the local strain and coordination environment: acute (SiO-Mo(O)2-OSi) angles and low coordination numbers at Mo lead to highly deshielded 95Mo chemical shifts and small quadrupolar coupling constants, respectively. Natural chemical shift analyses relate the 95Mo NMR signature of strained species to low LUMO energies, which is consistent with their high reducibility and corresponding reactivity. The 95Mo chemical shifts of supported Mo dioxo sites are thus linked to their specific electronic structures, providing a powerful descriptor for their propensity toward reduction and formation of active sites.
Collapse
Affiliation(s)
- Zachariah J Berkson
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Ran Zhu
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Christian Ehinger
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Lukas Lätsch
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Stefan P Schmid
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Darryl Nater
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Stephan Pollitt
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
- PSI, CH-5232 Villigen, Switzerland
| | | | - Snædís Björgvinsdóttir
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Alexander B Barnes
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| | - Yuriy Román-Leshkov
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Gregory A Price
- Applied Sciences, bp Innovation & Engineering, BP plc, Saltend, Hull HU12 8DS, U.K
| | - Glenn J Sunley
- Applied Sciences, bp Innovation & Engineering, BP plc, Saltend, Hull HU12 8DS, U.K
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Zürich CH-8093, Switzerland
| |
Collapse
|