1
|
Dombrowski JP, Kalendra V, Ziegler MS, Lakshmi KV, Bell AT, Tilley TD. M-Ge-Si thermolytic molecular precursors and models for germanium-doped transition metal sites on silica. Dalton Trans 2024; 53:7340-7349. [PMID: 38602311 DOI: 10.1039/d4dt00644e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
The synthesis, thermolysis, and surface organometallic chemistry of thermolytic molecular precursors based on a new germanosilicate ligand platform, -OGe[OSi(OtBu)3]3, is described. Use of this ligand is demonstrated with preparation of complexes containing the first-row transition metals Cr, Mn, and Fe. The thermolysis and grafting behavior of the synthesized complexes, Fe{OGe[OSi(OtBu)3]3}2 (FeGe), Mn{OGe[OSi(OtBu)3]3}2(THF)2 (MnGe) and Cr{OGe[OSi(OtBu)3]3}2(THF)2 (CrGe), was evaluated using a combination of thermogravimetric analysis; nuclear magnetic resonance (NMR), ultraviolet-visible (UV-Vis), and electron paramagnetic resonance (EPR) spectroscopies; and single-crystal X-ray diffraction (XRD). Grafting of the precursors onto SBA-15 mesoporous silica and subsequent calcination in air led to substantial changes in transition metal coordination environments and oxidation states, the implications of which are discussed in the context of low-coordinate and low oxidation state thermolytic molecular precursors.
Collapse
Affiliation(s)
- James P Dombrowski
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - Vidmantas Kalendra
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Micah S Ziegler
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| | - K V Lakshmi
- Department of Chemistry and Chemical Biology and The Baruch '60 Center for Biochemical Solar Energy Research, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Alexis T Bell
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, 201 Gilman Hall, Berkeley, CA, USA
| | - T Don Tilley
- Department of Chemistry, University of California, Berkeley, Berkeley, CA, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, USA
| |
Collapse
|
2
|
Nifant'ev I, Komarov P, Sadrtdinova G, Safronov V, Kolosov N, Ivchenko P. Mechanistic Insights of Ethylene Polymerization on Phillips Chromium Catalysts. Polymers (Basel) 2024; 16:681. [PMID: 38475365 DOI: 10.3390/polym16050681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/28/2024] [Accepted: 02/29/2024] [Indexed: 03/14/2024] Open
Abstract
Silica-supported chromium oxide catalysts, also named Phillips chromium catalysts (PCCs), provide more than half of the world's production of high- and medium-density polyethylenes. PCCs are usually prepared in the Cr(VI)/SiO2 form, which is subjected to reductive activation. It has been explicitly proven that CO reduces Cr(VI) to Cr(II) species that initiate ethylene polymerization; ethylene activates Cr(VI) sites as well, but the nature of the catalytic species is complicated by the presence of the ethylene oxidation products. It is widely accepted that the catalytic species are of a Cr(III)-alkyl nature, but this common assumption faces the challenge of "extra" hydrogen: the formation of similar species under the action of even-electron reducing agents requires an additional H atom. Relatively recently, it was found that saturated hydrocarbons can also activate CrOx/SiO2, and alkyl fragments turn out to be bonded with a polyethylene chain. In recent years, there have been numerous experimental and theoretical studies of the structure and chemistry of PCCs at the different stages of preparation and activation. The use of modern spectral methods (such as extended X-ray absorption fine structure (EXAFS), X-ray absorption near-edge structure (XANES), and others); operando IR, UV-vis, EPR, and XAS spectroscopies; and theoretical approaches (DFT modeling, machine learning) clarified many essential aspects of the mechanisms of CrOx/SiO2 activation and catalytic behavior. Overall, the Cosse-Arlman mechanism of polymerization on Cr(III)-alkyl centers is confirmed in many works, but its theoretical support required the development of nontrivial and contentious mechanistic concepts of Cr(VI)/SiO2 or Cr(II)/SiO2 activation. On the other hand, conflicting experimental data continue to be obtained, and certain mechanistic concepts are being developed with the use of outdated models. Strictly speaking, the main question of what type of catalytic species, Cr(II), Cr(III), or Cr(IV), comes into polymerization still has not received an unambiguous answer. The role of the chemical nature of the support-through the prism of the nature, geometry, and distribution of the active sites-is also not clear in depth. In the present review, we endeavored to summarize and discuss the recent studies in the field of the preparation, activation, and action of PCCs, with a focus on existing contradictions in the interpretation of the experimental and theoretical results.
Collapse
Affiliation(s)
- Ilya Nifant'ev
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Department of Chemistry, M.V. Lomonosov Moscow University, 1-3 Leninskie Gory, 119991 Moscow, Russia
| | - Pavel Komarov
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
| | - Guzelia Sadrtdinova
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Faculty of Chemistry, National Research University Higher School of Economics, Myasnitskaya St. 20, 101100 Moscow, Russia
| | | | | | - Pavel Ivchenko
- A.V. Topchiev Institute of Petrochemical Synthesis RAS, 29 Leninsky Pr., 119991 Moscow, Russia
- Department of Chemistry, M.V. Lomonosov Moscow University, 1-3 Leninskie Gory, 119991 Moscow, Russia
| |
Collapse
|
3
|
Ashuiev A, Giorgia Nobile A, Trummer D, Klose D, Guda S, Safonova OV, Copéret C, Guda A, Jeschke G. Active Sites in Cr(III)-Based Ethylene Polymerization Catalysts from Machine-Learning-Supported XAS and EPR Spectroscopy. Angew Chem Int Ed Engl 2024; 63:e202313348. [PMID: 37970660 DOI: 10.1002/anie.202313348] [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: 09/08/2023] [Revised: 10/13/2023] [Accepted: 11/16/2023] [Indexed: 11/17/2023]
Abstract
The ethylene polymerization Phillips catalyst has been employed for decades and is central to the polymer industry. While Cr(III) alkyl species are proposed to be the propagating sites, there is so far no direct experimental evidence for such proposal. In this work, by coupling Surface organometallic chemistry, EPR spectroscopy, and machine learning-supported XAS studies, we have studied the electronic structure of well-defined silica-supported Cr(III) alkyls and identified the presence of several surface species in high and low-spin states, associated with different coordination environments. Notably, low-spin Cr(III) sites are shown to participate in ethylene polymerization, indicating that similar Cr(III) alkyl species could be involved in the related Phillips catalyst.
Collapse
Affiliation(s)
- Anton Ashuiev
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Anna Giorgia Nobile
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - David Trummer
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Daniel Klose
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Sergey Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, 344090, Russia
| | - Olga V Safonova
- Paul Scherrer Institut, WLGA/217, Forschungsstrasse 111, 5232, Villigen PSI, Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| | - Alexander Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, 344090, Russia
| | - Gunnar Jeschke
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, 8093, Zürich, Switzerland
| |
Collapse
|
4
|
Hall JN, Chapovetsky A, Kanbur U, Kim YL, McCullough KE, Syed ZH, Johnson CS, Ferrandon MS, Liu C, Kropf AJ, Delferro M, Kaphan DM. Oxidative Grafting for Catalyst Synthesis in Surface Organometallic Chemistry. ACS APPLIED MATERIALS & INTERFACES 2023; 15:53498-53514. [PMID: 37945527 DOI: 10.1021/acsami.3c12656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The development of new methods of catalyst synthesis with the potential to generate active site structures orthogonal to those accessible by traditional protocols is of great importance for discovering new materials for addressing challenges in the evolving energy and chemical economy. In this work, the generality of oxidative grafting of organometallic and well-defined molecular metal precursors onto redox-active surfaces such as manganese dioxide (MnO2) and lithium manganese oxide (LiMn2O4) is investigated. Nine molecular metal precursors are explored, spanning groups 4-11 and each of the three periods of the transition metal series. The byproducts of the oxidative grafting reaction, a mixture of protodemetalation and ligand homocoupling for several organometallic precursors, was found to provide insights into the mechanism of the grafting reaction, suggesting oxidation of both the metal d-orbitals, as well as the metal-carbon σ-bonds, resulting in ejection of the ligand radical fragment. Analysis of the supported structures and oxidation state by X-ray absorption spectroscopy (XAS) and X-ray photoelectron spectroscopy (XPS) suggests that several of the chemisorbed metal ions are intercalated into interstitial vacancies of the surface structure while other complexes form intact molecular fragments on the surface. Proof of concept for the use of this metalation protocol to generate diverse, metal-dependent catalytic performance is demonstrated by the application of these materials in the conversion of cyclohexane to K/A oil (cyclohexanol and cyclohexanone) with tert-butyl hydroperoxide, as well as in the low-temperature (T ≤ 50 °C) oxidation of carbon monoxide to carbon dioxide.
Collapse
Affiliation(s)
- Jacklyn N Hall
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Alon Chapovetsky
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Uddhav Kanbur
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Yu Lim Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Katherine E McCullough
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Zoha H Syed
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Christopher S Johnson
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Magali S Ferrandon
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Cong Liu
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - A Jeremy Kropf
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Massimiliano Delferro
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - David M Kaphan
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| |
Collapse
|
5
|
Reckziegel A, Battistella B, Schmidt A, Werncke CG. Intricate Road to Linear Anionic Nickel(I) Hexamethyldisilazanide [Ni(N(SiMe 3) 2) 2] . Inorg Chem 2022; 61:7794-7803. [PMID: 35522526 DOI: 10.1021/acs.inorgchem.2c00214] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this report, we present intricate pathways for the synthesis of linear nickel(I) silylamide K{m}[Ni(NR2)2] (NR2 = -N(SiMe3)2). This is achieved first via the reduction of nickel(II) trisamide Li(donor)4[Ni(NR2)3] (Li(thf)x[1]) with KC8 in the presence of 18-crown-6 or crypt.222. In due course, the behavior of Li(donor)4[Ni(NR2)3] as a source of masked two-coordinate nickel(II) hexamethyldisilazanide is explored, leading to the formation of nickel(I) and nickel(II) N-donor adducts, as well as metal-metal-bonded dinickel(I) trisamide K(toluene)[Ni2(NR2)3] (K(toluene)[5]). Finally, a convenient and reliable synthesis of K{m}[Ni(NR2)2] by ligand exchange of phosphines in [Ni(NR2)(PPh3)2] with K{m}(NR2) is presented. This allows for the comprehensive analysis of its electronic properties which reveals a fluxional behavior in solution with tight anion/cation interactions.
Collapse
Affiliation(s)
- Alexander Reckziegel
- Department of Chemistry, Philipps University Marburg, Hans-Meerwein Straße 4, D-35037 Marburg, Germany
| | - Beatrice Battistella
- Institute of Chemistry, Humboldt-University Berlin, Brook-Taylor-Str. 2, D-12489 Berlin, Germany
| | - Andreas Schmidt
- Department of Chemistry, Philipps University Marburg, Hans-Meerwein Straße 4, D-35037 Marburg, Germany
| | - C Gunnar Werncke
- Department of Chemistry, Philipps University Marburg, Hans-Meerwein Straße 4, D-35037 Marburg, Germany
| |
Collapse
|
6
|
Trzmiel SPO, Langmann J, Maichle-Mössmer C, Anwander R. Chromous siloxides of variable nuclearity and magnetism. Dalton Trans 2022; 51:5072-5081. [PMID: 35262151 DOI: 10.1039/d2dt00354f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Treatment of Cr[N(SiMe3)2]2(thf)2 with HOSiR3 (R = Et, iPr) in THF afforded the bridged CrII siloxide complexes Cr3(OSiEt3)2(μ-OSiEt3)4(thf)2 and Cr2(OSiiPr3)2(μ-OSiiPr3)2(thf)2 in high yield. Exposure of these compounds to vacuum in aliphatic solvents led to the loss of coordinated THF and to the formation of the homoleptic chromous siloxides Cr4(μ-OSiEt3)8 and Cr3(OSiiPr3)2(μ-OSiiPr3)4, respectively, in moderate to high yield. Use of TMEDA as a potentially bidentate donor molecule gave the monomeric cis-coordinated siloxide Cr(OSiiPr3)2(tmeda) (tmeda = N,N,N',N'-tetramethylethane-1,2-diamine). Oxidation of Cr2(OSiiPr3)2(μ-OSiiPr3)2(thf)2 with CHI3 and C2Cl6 produced the trigonal bipyramidal chromic compound CrIII(OSiiPr)3(thf)2 and asymmetrically coordinated Cr2Cl3(OSiiPr3)3(thf)3, respectively. Magnetic measurements (Evans and SQUID) hinted at (a) antiferromagnetic interactions between the CrII centres, (b) revealed higher effective magnetic moments (μeff) for cis-coordinated monomeric heteroleptic complexes compared to trans-coordinated ones, and (c) pointed out the highest (μeff) for the tetranuclear complex Cr4(μ-OSiEt3)8 (6.26μB, SQUID, 300 K; Cr⋯Cradjacent avg. 2.535 A).
Collapse
Affiliation(s)
- Simon P O Trzmiel
- Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany.
| | - Jan Langmann
- Institut für Physik, Universität Augsburg, Universitätsstr. 1, 86159 Augsburg, Germany
| | - Cäcilia Maichle-Mössmer
- Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany.
| | - Reiner Anwander
- Institute of Inorganic Chemistry, Eberhard Karls Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany.
| |
Collapse
|
7
|
Weller R, Völlinger L, Werncke CG. On the Synthesis and Reduction of Trigonal Halido Bis(silylamido) Metalates of Chromium to Cobalt. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100716] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Ruth Weller
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Germany
| | - Lena Völlinger
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Germany
| | - C. Gunnar Werncke
- Fachbereich Chemie Philipps-Universität Marburg Hans-Meerwein-Straße 4 35032 Marburg Germany
| |
Collapse
|
8
|
|
9
|
Ishizaka Y, Arai N, Matsumoto K, Nagashima H, Takeuchi K, Fukaya N, Yasuda H, Sato K, Choi JC. Bidentate Disilicate Framework for Bis-Grafted Surface Species. Chemistry 2021; 27:12069-12077. [PMID: 34189785 DOI: 10.1002/chem.202101927] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Indexed: 11/08/2022]
Abstract
Recent advances in surface organometallic chemistry have enabled the detailed characterization of the surface species in single-site heterogeneous catalysts. However, the selective formation of bis-grafted surface species remains challenging because of the heterogeneity of the supporting surface. Herein, we introduce a metal complex bearing bidentate disilicate ligands, -OSi(Ot Bu)2 OSi(Ot Bu)2 O-, as a molecular precursor, which has a silicate framework adjacent to the metal (Pt) center. The grafting of the precursors on silica supports (MCM-41 and CARiACT Q10) proceeded through a substitution reaction on the silicon atoms of the disilicate ligand, which was verified by the detection of isobutene and t BuOH as the elimination products, to selectively yield bis-grafted surface species. The chemical structure of the surface species was characterized by solid-state NMR, and the chemical shift values of the ancillary ligands and 195 Pt nuclei suggested that the bidentate coordination sphere was maintained following grafting.
Collapse
Affiliation(s)
- Yusuke Ishizaka
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.,Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8573, Japan
| | - Natsumi Arai
- Graduate School of Science and Engineering, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki, 310-8512, Japan
| | - Kazuhiro Matsumoto
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Hiroki Nagashima
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Katsuhiko Takeuchi
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Norihisa Fukaya
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Hiroyuki Yasuda
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Kazuhiko Sato
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
| | - Jun-Chul Choi
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan.,Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8573, Japan
| |
Collapse
|
10
|
Praveen CS, Borosy AP, Copéret C, Comas-Vives A. Strain in Silica-Supported Ga(III) Sites: Neither Too Much nor Too Little for Propane Dehydrogenation Catalytic Activity. Inorg Chem 2021; 60:6865-6874. [PMID: 33545002 PMCID: PMC8483445 DOI: 10.1021/acs.inorgchem.0c03135] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Well-defined Ga(III) sites on SiO2 are highly active, selective, and stable catalysts in the propane dehydrogenation (PDH) reaction. In this contribution, we evaluate the catalytic activity toward PDH of tricoordinated and tetracoordinated Ga(III) sites on SiO2 by means of first-principles calculations using realistic amorphous periodic SiO2 models. We evaluated the three reaction steps in PDH, namely, the C-H activation of propane to form propyl, the β-hydride (β-H) transfer to form propene and a gallium hydride, and the H-H coupling to release H2, regenerating the initial Ga-O bond and closing the catalytic cycle. Our work shows how Brønsted-Evans-Polanyi relationships are followed to a certain extent for these three reaction steps on Ga(III) sites on SiO2 and highlights the role of the strain of the reactive Ga-O pairs on such sites of realistic amorphous SiO2 models. It also shows how transition-state scaling holds very well for the β-H transfer step. While highly strained sites are very reactive sites for the initial C-H activation, they are more difficult to regenerate. The corresponding less strained sites are not reactive enough, pointing to the need for the right balance in strain to be an effective site for PDH. Overall, our work provides an understanding of the intrinsic activity of acidic Ga single sites toward the PDH reaction and paves the way toward the design and prediction of better single-site catalysts on SiO2 for the PDH reaction.
Collapse
Affiliation(s)
- C S Praveen
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - A P Borosy
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - C Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog-Weg 1-5, CH-8093 Zürich, Switzerland
| | - A Comas-Vives
- Department of Chemistry, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Catalonia, Spain
| |
Collapse
|
11
|
Trummer D, Searles K, Algasov A, Guda SA, Soldatov AV, Ramanantoanina H, Safonova OV, Guda AA, Copéret C. Deciphering the Phillips Catalyst by Orbital Analysis and Supervised Machine Learning from Cr Pre-edge XANES of Molecular Libraries. J Am Chem Soc 2021; 143:7326-7341. [PMID: 33974429 DOI: 10.1021/jacs.0c10791] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Unveiling the nature and the distribution of surface sites in heterogeneous catalysts, and for the Phillips catalyst (CrO3/SiO2) in particular, is still a grand challenge despite more than 60 years of research. Commonly used references in Cr K-edge XANES spectral analysis rely on bulk materials (Cr-foil, Cr2O3) or molecules (CrCl3) that significantly differ from actual surface sites. In this work, we built a library of Cr K-edge XANES spectra for a series of tailored molecular Cr complexes, varying in oxidation state, local coordination environment, and ligand strength. Quantitative analysis of the pre-edge region revealed the origin of the pre-edge shape and intensity distribution. In particular, the characteristic pre-edge splitting observed for Cr(III) and Cr(IV) molecular complexes is directly related to the electronic exchange interactions in the frontier orbitals (spin-up and -down transitions). The series of experimental references was extended by theoretical spectra for potential active site structures and used for training the Extra Trees machine learning algorithm. The most informative features of the spectra (descriptors) were selected for the prediction of Cr oxidation states, mean interatomic distances in the first coordination sphere, and type of ligands. This set of descriptors was applied to uncover the site distribution in the Phillips catalyst at three different stages of the process. The freshly calcined catalyst consists of mainly Cr(VI) sites. The CO-exposed catalyst contains mainly Cr(II) silicates with a minor fraction of Cr(III) sites. The Phillips catalyst exposed to ethylene contains mainly highly coordinated Cr(III) silicates along with unreduced Cr(VI) sites.
Collapse
Affiliation(s)
- David Trummer
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Keith Searles
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Alexander Algasov
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090.,Institute of Mathematics, Mechanics and Computer Science, Southern Federal University, Milchakova 8a, Rostov-on-Don, Russia, 344090
| | - Sergey A Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090.,Institute of Mathematics, Mechanics and Computer Science, Southern Federal University, Milchakova 8a, Rostov-on-Don, Russia, 344090
| | - Alexander V Soldatov
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090
| | | | | | - Alexander A Guda
- The Smart Materials Research Institute, Southern Federal University, Sladkova 178/24, Rostov-on-Don, Russia, 344090
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| |
Collapse
|
12
|
Vandervelden CA, Khan SA, Peters B. Importance learning estimator for the site-averaged turnover frequency of a disordered solid catalyst. J Chem Phys 2020; 153:244120. [PMID: 33380094 DOI: 10.1063/5.0037450] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
For disordered catalysts such as atomically dispersed "single-atom" metals on amorphous silica, the active sites inherit different properties from their quenched-disordered local environments. The observed kinetics are site-averages, typically dominated by a small fraction of highly active sites. Standard sampling methods require expensive ab initio calculations at an intractable number of sites to converge on the site-averaged kinetics. We present a new method that efficiently estimates the site-averaged turnover frequency (TOF). The new estimator uses the same importance learning algorithm [Vandervelden et al., React. Chem. Eng. 5, 77 (2020)] that we previously used to compute the site-averaged activation energy. We demonstrate the method by computing the site-averaged TOF for a simple disordered lattice model of an amorphous catalyst. The results show that with the importance learning algorithm, the site-averaged TOF and activation energy can now be obtained concurrently with orders of magnitude reduction in required ab initio calculations.
Collapse
Affiliation(s)
- Craig A Vandervelden
- Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93106, USA
| | - Salman A Khan
- Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93106, USA
| | - Baron Peters
- Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| |
Collapse
|
13
|
Jongkind MK, van Kessel T, Velthoen MEZ, Friederichs N, Weckhuysen BM. Tuning the Redox Chemistry of a Cr/SiO 2 Phillips Catalyst for Controlling Activity, Induction Period and Polymer Properties. Chemphyschem 2020; 21:1665-1674. [PMID: 32539171 PMCID: PMC7496818 DOI: 10.1002/cphc.202000488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 06/12/2020] [Indexed: 11/06/2022]
Abstract
The Cr/SiO2 Phillips catalyst has taken a central role in ethylene polymerization ever since its discovery in 1953. This catalyst is unique compared to other ethylene polymerization catalysts, since it is active without the addition of a metal-alkyl co-catalyst. However, metal-alkyls can be added for scavenging poisons, enhancing the catalyst activity, reducing the induction period and altering polymer characteristics. Despite extensive research into the working state of the catalyst, still no consensus has been reached. Here, we show that by varying the type of metal-alkyl co-catalyst and its amount, the Cr redox chemistry can be tailored, resulting in distinct catalyst activities, induction periods, and polymer characteristics. We have used in-situ UV-Vis-NIR diffuse reflectance spectroscopy (DRS) for studying the Cr oxidation state during the reduction by tri-ethyl borane (TEB) or tri-ethyl aluminum (TEAl) and during subsequent ethylene polymerization. The results show that TEB primarily acts as a reductant and reduces Cr6+ with subsequent ethylene polymerization resulting in rapid polyethylene formation. TEAl generated two types of Cr2+ sites, inaccessible Cr3+ sites and active Cr4+ sites. Subsequent addition of ethylene also revealed an increased reducibility of residual Cr6+ sites and resulted in rapid polyethylene formation. Our results demonstrate the possibility of controlling the reduction chemistry by adding the proper amount and type of metal-alkyl for obtaining desired catalyst activities and tailored polyethylene characteristics.
Collapse
Affiliation(s)
- Maarten K. Jongkind
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Theo van Kessel
- SABICTechnology and Innovation DepartmentUrmonderbaan 226167RD GeleenThe Netherlands
| | - Marjolein E. Z. Velthoen
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| | - Nic. Friederichs
- SABICTechnology and Innovation DepartmentUrmonderbaan 226167RD GeleenThe Netherlands
| | - Bert M. Weckhuysen
- Inorganic Chemistry and CatalysisDebye Institute for Nanomaterial ScienceUtrecht UniversityUniversiteitsweg 993584 CGUtrechtThe Netherlands
| |
Collapse
|
14
|
Müller I, Munz D, Werncke CG. Reactions of Alkynes with Quasi-Linear 3d Metal(I) Silylamides of Chromium to Cobalt: A Comparative Study. Inorg Chem 2020; 59:9521-9537. [DOI: 10.1021/acs.inorgchem.0c00365] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Igor Müller
- Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
| | - Dominik Munz
- Inorganic Chemistry: Coordination Chemistry, Saarland University, 66123 Saarbrücken Germany
- Inorganic and General Chemistry, Friedrich-Alexander University Erlangen-Nürnberg, Egerlandstrasse 1, 91058 Erlangen, Germany
| | - C. Gunnar Werncke
- Department of Chemistry, Philipps-University Marburg, Hans-Meerwein-Straße 4, 35043 Marburg, Germany
| |
Collapse
|
15
|
Martino GA, Piovano A, Barzan C, Rabeah J, Agostini G, Bruekner A, Leone G, Zanchin G, Monoi T, Groppo E. Rationalizing the Effect of Triethylaluminum on the Cr/SiO 2 Phillips Catalysts. ACS Catal 2020. [DOI: 10.1021/acscatal.9b04726] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Giorgia A. Martino
- Department of Chemistry, NIS Centre and INSTM, University of Torino, via G. Quarello 15A, 10135 Torino, Italy
| | - Alessandro Piovano
- Department of Chemistry, NIS Centre and INSTM, University of Torino, via G. Quarello 15A, 10135 Torino, Italy
| | - Caterina Barzan
- Department of Chemistry, NIS Centre and INSTM, University of Torino, via G. Quarello 15A, 10135 Torino, Italy
| | - Jabor Rabeah
- Leibniz Institute for Catalysis at the University of Rostock (LIKAT), Albert-Einstein-Str. 29, D-18059 Rostock, Germany
| | - Giovanni Agostini
- Leibniz Institute for Catalysis at the University of Rostock (LIKAT), Albert-Einstein-Str. 29, D-18059 Rostock, Germany
| | - Angelika Bruekner
- Leibniz Institute for Catalysis at the University of Rostock (LIKAT), Albert-Einstein-Str. 29, D-18059 Rostock, Germany
| | - Giuseppe Leone
- CNR, Istituto di Scienze e Tecnologie Chimiche “Giulio Natta” (SCITEC), via A. corti 12, I-20133 Milano, Italy
| | - Giorgia Zanchin
- CNR, Istituto di Scienze e Tecnologie Chimiche “Giulio Natta” (SCITEC), via A. corti 12, I-20133 Milano, Italy
| | - Takashi Monoi
- R&D Division, Japan Polychem Corporation, 1-1 Marunouchi 1-chome, Chiyoda-ku, 100-8251 Tokyo, Japan
| | - Elena Groppo
- Department of Chemistry, NIS Centre and INSTM, University of Torino, via G. Quarello 15A, 10135 Torino, Italy
| |
Collapse
|
16
|
Yelin S, Limberg C. Molecular Structural Motifs and O2 Activation Inspired by Enzymes and Solid Catalysts. Catal Letters 2020. [DOI: 10.1007/s10562-019-02918-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
17
|
Ghaffari B, Mendes‐Burak J, Chan KW, Copéret C. Silica‐Supported MnIISites as Efficient Catalysts for Carbonyl Hydroboration, Hydrosilylation, and Transesterification. Chemistry 2019; 25:13869-13873. [DOI: 10.1002/chem.201903638] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Behnaz Ghaffari
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Jorge Mendes‐Burak
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Ka Wing Chan
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| |
Collapse
|
18
|
Guda AA, Guda SA, Lomachenko KA, Soldatov MA, Pankin IA, Soldatov AV, Braglia L, Bugaev AL, Martini A, Signorile M, Groppo E, Piovano A, Borfecchia E, Lamberti C. Quantitative structural determination of active sites from in situ and operando XANES spectra: From standard ab initio simulations to chemometric and machine learning approaches. Catal Today 2019. [DOI: 10.1016/j.cattod.2018.10.071] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
19
|
Reduction of 2,2′-Bipyridine by Quasi-Linear 3d-Metal(I) Silylamides—A Structural and Spectroscopic Study. INORGANICS 2019. [DOI: 10.3390/inorganics7100117] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Quasi-linear anionic 3d-metal(I) silylamides are a new and promising class of molecules. Due to their highly negative reduction potential we wanted to test their capability to reduce substrates under coordination of their monoanionic radicaloid form. In a proof of principle study, we present the results of the reaction of metal(I) silylamides of chromium to cobalt with 2,2′-bipyridine (bipy), the redox non-innocence and reducibility of which was already established. In the course of these studies complexes of the type K{18-crown-6}[M(hmds)2(bipy)] (hmds = –N(SiMe3)2) were obtained. These compounds were isolated and thoroughly characterized to confirm the electron transfer onto the bipyridine ligand, which now acts as a radical monoanion. For comparison of the structural changes of the bipyridine ligand, the analogous zinc complexes were also synthesized. Overall our results indicate that anionic metal(I) silylamides are capable of reducing and ligate substrates, even when the electrochemical reduction potential of the latter is by up to 1 V higher.
Collapse
|
20
|
Cruz CA, Monwar MM, Barr J, McDaniel MP. Identification of the Starting Group on the First PE Chain Produced by the Phillips Catalyst. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00588] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. A. Cruz
- Chevron Phillips Chemical Company LP, Phillips 66 Research Center, Bartlesville, Oklahoma 74003, United States
| | - M. M. Monwar
- Chevron Phillips Chemical Company LP, Phillips 66 Research Center, Bartlesville, Oklahoma 74003, United States
| | - J. Barr
- Chevron Phillips Chemical Company LP, Phillips 66 Research Center, Bartlesville, Oklahoma 74003, United States
| | - M. P. McDaniel
- Chevron Phillips Chemical Company LP, Phillips 66 Research Center, Bartlesville, Oklahoma 74003, United States
| |
Collapse
|
21
|
Meyet J, Searles K, Newton MA, Wörle M, van Bavel AP, Horton AD, van Bokhoven JA, Copéret C. Monomeric Copper(II) Sites Supported on Alumina Selectively Convert Methane to Methanol. Angew Chem Int Ed Engl 2019; 58:9841-9845. [DOI: 10.1002/anie.201903802] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 04/21/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Jordan Meyet
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Keith Searles
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Mark A. Newton
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Michael Wörle
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | | | - Andrew D. Horton
- Shell Global Solutions International B.V. Grasweg 31 1031 HW Amsterdam The Netherlands
| | - Jeroen A. van Bokhoven
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
- Laboratory for Catalysis and Sustainable ChemistryPaul Scherrer Institute 5232 Villigen Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied BiosciencesETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| |
Collapse
|
22
|
Pucino M, Allouche F, Gordon CP, Wӧrle M, Mougel V, Copéret C. A reactive coordinatively saturated Mo(iii) complex: exploiting the hemi-lability of tris( tert-butoxy)silanolate ligands. Chem Sci 2019; 10:6362-6367. [PMID: 31341592 PMCID: PMC6601292 DOI: 10.1039/c9sc01955c] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 05/13/2019] [Indexed: 12/15/2022] Open
Abstract
Hemilabile tris(tert-butoxy)silanolate ligands allow stabilizing a mononuclear octahedral Mo(iii) complex without quenching its reactivity towards small molecules (N2, CO2, N2O).
Coordinatively unsaturated Mo(iii) complexes have been identified as highly reactive species able to activate dinitrogen without the need for a sacrificial reducing agent. Here, we report a coordinatively saturated octahedral Mo(iii) complex stabilized by κ2-tris(tert-butoxy)silanolate ligands, which is yet highly reactive towards dinitrogen and small molecules. The combined high stability and activity are ascribed to the dual binding mode of the tris(tert-butoxy)silanolate ligands that allow unlocking a coordination site in the presence of reactive small molecules to promote their activation at low temperatures.
Collapse
Affiliation(s)
- Margherita Pucino
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| | - Florian Allouche
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| | - Christopher P Gordon
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| | - Michael Wӧrle
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| | - Victor Mougel
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences , ETH Zurich , Vladimir-Prelog-Weg 2 , 8093 Zurich , Switzerland . ;
| |
Collapse
|
23
|
Copéret C. Single-Sites and Nanoparticles at Tailored Interfaces Prepared via Surface Organometallic Chemistry from Thermolytic Molecular Precursors. Acc Chem Res 2019; 52:1697-1708. [PMID: 31150207 DOI: 10.1021/acs.accounts.9b00138] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Heterogeneous catalysts are complex by nature, making particularly difficult to assess the structure of their active sites. Such complexity is inherited in part from their mode of preparation, which typically involves coprecipitation or impregnation of metal salts in aqueous solution, and the associated complex surface chemistries. In this context, surface organometallic chemistry (SOMC) has emerged as a powerful approach to generate well-defined surface species, where the metal sites are introduced by grafting tailored molecular precursors. When combined with thermolytic molecular precursors (TMPs) that can lose their organic moieties quite readily upon thermal treatment, SOMC provides access to supported isolated metal sites with defined oxidation state and nuclearity inherited from the precursor. The resulting surface species bear unusual coordination imposed by the surface that provides them high reactivity in comparison with their molecular precursor. In addition, these molecularly defined species bare strong resemblance with the active sites of supported metal oxides. However, they typically contain a higher proportion of active sites making structure-activity relationship possible. They thus constitute ideal models for this important class of industrial catalysts that are used in numerous applications such as olefin epoxidation (Shell process), olefin metathesis (triolefin process), ethylene polymerization (Phillips catalysts), or propane dehydrogenation (Catofin and related processes). This SOMC/TMP approach can thus provide detailed information about the structure of active sites in industrial catalysts, their mode of initiation and deactivation, as well as the role of the support and specific thermal treatment on the final activity of the catalysts. Nonetheless, these structurally characterized surface sites still exhibit heterogeneous environments borrowed from the support itself, that explain the intrinsic complexity of heterogeneous catalysis. Furthermore, SOMC/TMP can also be used to generate and investigate supported metal nanoparticles. Starting from the well-defined isolated sites, that also contain adjacent surface OH groups, one can graft a second metal and then generate after treatment under hydrogen small and narrowly dispersed alloys or nanoparticles with tailored interfaces that can show improved catalytic performances and are amiable to detailed structure-activity relationships. This approach is illustrated by two case studies: (1) formation of supported copper nanoparticles at tailored interfaces that contain isolated metal sites for the selective hydrogenation of carbon dioxide to methanol, allowing for a detailed understanding of the role of dopants and supports in heterogeneous catalysis, and (2) preparation of highly selective and productive propane dehydrogenation catalysts based on silica-supported Pt xGa y alloy. Overall, this Account shows how the combination of SOMC and TMP helps to generate catalysts, particularly suited for elucidating structural characterization of active sites at a molecular-level which in turn enables structure-activity relationship to be drawn. Such detailed information obtained on well-defined catalysts can then be used to understand complex effects observed in industrial catalysts (effects of supports, additives, dopants, etc.), and to extract information that can then be used to improve them in a more rational way.
Collapse
Affiliation(s)
- Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg. 1-5, CH-8093 Zürich, Switzerland
| |
Collapse
|
24
|
Monomeric Copper(II) Sites Supported on Alumina Selectively Convert Methane to Methanol. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201903802] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
25
|
Bucinsky L, Breza M, Malček M, Powers DC, Hwang SJ, Krzystek J, Nocera DG, Telser J. High-Frequency and -Field EPR (HFEPR) Investigation of a Pseudotetrahedral CrIV Siloxide Complex and Computational Studies of Related CrIVL4 Systems. Inorg Chem 2019; 58:4907-4920. [DOI: 10.1021/acs.inorgchem.8b03512] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Lukas Bucinsky
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-81237 Bratislava, Slovakia
| | - Martin Breza
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-81237 Bratislava, Slovakia
| | - Michal Malček
- Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology, Radlinského 9, SK-81237 Bratislava, Slovakia
| | - David C. Powers
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Seung Jun Hwang
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - J. Krzystek
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, United States
| | - Daniel G. Nocera
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Joshua Telser
- Department of Biological, Physical and Health Sciences, Roosevelt University, Chicago, Illinois 60605, United States
| |
Collapse
|
26
|
Feng PF, Kong MY, Yang YW, Su PR, Shan CF, Yang XX, Cao J, Liu WS, Feng W, Tang Y. Eu 2+/Eu 3+-Based Smart Duplicate Responsive Stimuli and Time-gated Nanohybrid for Optical Recording and Encryption. ACS APPLIED MATERIALS & INTERFACES 2019; 11:1247-1253. [PMID: 30516048 DOI: 10.1021/acsami.8b17281] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
With the rapid development of information science, it is urgent that memory devices possessing high security, density, and desirable storage ability should be developed. In this work, a smart duplicate response of stimuli has been developed and a time-gate nanohybrid based on variable valence Eu2+/Eu3+ coencapsulated has been fabricated and acts as active material in the multilevel and multidimensional memory devices. The luminescence lifetime of Eu3+ in this nanohybrid gave a stimuli response due to which the energy level of the coordinated ligand could be modulated. Furthermore, by a simple sintering procedure, Eu3+ was partially in situ reduced to Eu2+ with a short lifetime in the system. And the in situ reduction ensured both Eu3+ and Eu2+ ions' uniform distribution in the nanohybrid and simultaneous response upon light excitation of variable valence Eu ions. Interestingly, Eu3+ revealed a prolonged lifetime because of the presence of an energy-transfer effect of Eu2+ → Eu3+. Such a nanohybrid had abundant luminescent properties, including the short lifetime of Eu2+, the energy transfer from the Eu2+ to Eu3+ ions, and the stimuli response of the Eu3+ lifetimes when exposed to acidic or basic vapor, thus giving birth to interesting recording and encryption performance in spatial-temporal dimensions. We believe that this research will point out a new direction for the future development of multilevel and multidimensional optical recording and encryption materials.
Collapse
Affiliation(s)
- Peng-Fei Feng
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Meng-Ya Kong
- Department of Chemistry , Fudan University , Shanghai 200438 , China
| | - Yi-Wei Yang
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Ping-Ru Su
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Chang-Fu Shan
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Xiao-Xi Yang
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Jing Cao
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Wei-Sheng Liu
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Wei Feng
- Department of Chemistry , Fudan University , Shanghai 200438 , China
| | - Yu Tang
- State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| |
Collapse
|
27
|
Leone G, Groppo E, Zanchin G, Martino GA, Piovano A, Bertini F, Martí-Rujas J, Parisini E, Ricci G. Concerted Electron Transfer in Iminopyridine Chromium Complexes: Ligand Effects on the Polymerization of Various (Di)olefins. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00812] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Giuseppe Leone
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), via A. Corti 12, I-20133 Milano, Italy
| | - Elena Groppo
- Dipartimento di Chimica, NIS Interdepartmental Research Center and INSTM Reference Center, Università degli Studi di Torino, Via G. Quarello 15A, I-10135 Torino, Italy
| | - Giorgia Zanchin
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), via A. Corti 12, I-20133 Milano, Italy
| | - Giorgia A. Martino
- Dipartimento di Chimica, NIS Interdepartmental Research Center and INSTM Reference Center, Università degli Studi di Torino, Via G. Quarello 15A, I-10135 Torino, Italy
| | - Alessandro Piovano
- Dipartimento di Chimica, NIS Interdepartmental Research Center and INSTM Reference Center, Università degli Studi di Torino, Via G. Quarello 15A, I-10135 Torino, Italy
| | - Fabio Bertini
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), via A. Corti 12, I-20133 Milano, Italy
| | - Javier Martí-Rujas
- Center for Nano Science and Technology at Polimi, Istituto Italiano di Tecnologia, Via Pascoli 70/3, I-20133 Milano, Italy
| | - Emilio Parisini
- Center for Nano Science and Technology at Polimi, Istituto Italiano di Tecnologia, Via Pascoli 70/3, I-20133 Milano, Italy
| | - Giovanni Ricci
- CNR-Istituto per lo Studio delle Macromolecole (ISMAC), via A. Corti 12, I-20133 Milano, Italy
| |
Collapse
|
28
|
Culver DB, Conley MP. Activation of C−F Bonds by Electrophilic Organosilicon Sites Supported on Sulfated Zirconia. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809199] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Damien B. Culver
- Chemistry University of California, Riverside 501 Big Springs Rd. Riverside CA 92521 USA
| | - Matthew P. Conley
- Chemistry University of California, Riverside 501 Big Springs Rd. Riverside CA 92521 USA
| |
Collapse
|
29
|
Werner D, Anwander R. Unveiling the Takai Olefination Reagent via Tris( tert-butoxy)siloxy Variants. J Am Chem Soc 2018; 140:14334-14341. [PMID: 30213182 DOI: 10.1021/jacs.8b08739] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The elusive Takai olefination reagent, namely, the iodo-methylidene Cr(III) complex [Cr2Cl4(CHI)(thf)4], has been isolated by careful handling of the reaction between CrCl2 and CHI3 in THF at -35 °C. Alternatively, treatment of [Cr(OSi(O tBu)3)2] with CHI3 gave the mixed-valent dihalido-methanide complex [CrII/III2I2(OSi(O tBu)3)2(CHI2)], featuring a Cr(III)-CHI2 moiety. In the presence of TMEDA nucleophilic attack at CHI2 occurred generating the zwitterionic species [CrIII(OSi(O tBu)3)2(tmeda-CHI)][I]. Complexes [Cr2Cl4(CHI)(thf)4] and [CrII/III2I2(OSi(O tBu)3)2(CHI2)] were screened for their ability to induce monohalido olefination of benzaldehyde. Remarkably, both complexes promote olefination, with [Cr2Cl4(CHI)(thf)4] accomplishing the same E selectivity as Takai 's original mixture. Complex [CrII/III2I2(OSi(O tBu)3)2(CHI2)], however, appeared to give preferentially Z isomer, corroborating the monoiodo-methylidene species Cr(III)-CHI-Cr(III) as the active olefination component of the original in situ generated Takai reagent mixture.
Collapse
Affiliation(s)
- Daniel Werner
- Institut für Anorganische Chemie , Eberhard Karls Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| | - Reiner Anwander
- Institut für Anorganische Chemie , Eberhard Karls Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany
| |
Collapse
|
30
|
Culver DB, Conley MP. Activation of C−F Bonds by Electrophilic Organosilicon Sites Supported on Sulfated Zirconia. Angew Chem Int Ed Engl 2018; 57:14902-14905. [PMID: 30265766 DOI: 10.1002/anie.201809199] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Damien B. Culver
- Chemistry University of California, Riverside 501 Big Springs Rd. Riverside CA 92521 USA
| | - Matthew P. Conley
- Chemistry University of California, Riverside 501 Big Springs Rd. Riverside CA 92521 USA
| |
Collapse
|
31
|
Groppo E, Martino GA, Piovano A, Barzan C. The Active Sites in the Phillips Catalysts: Origins of a Lively Debate and a Vision for the Future. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02521] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Elena Groppo
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Giorgia Antonina Martino
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Alessandro Piovano
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| | - Caterina Barzan
- Department of Chemistry, NIS Centre and INSTM, University of Torino, Via Quarello 15/A, 10125 Torino, Italy
| |
Collapse
|
32
|
Liu C, Camacho-Bunquin J, Ferrandon M, Savara A, Sohn H, Yang D, Kaphan DM, Langeslay RR, Ignacio-de Leon PA, Liu S, Das U, Yang B, Hock AS, Stair PC, Curtiss LA, Delferro M. Development of activity–descriptor relationships for supported metal ion hydrogenation catalysts on silica. Polyhedron 2018. [DOI: 10.1016/j.poly.2018.06.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
33
|
Zeng Y, Liu S, Terano M. Silsesquioxane-Supported Chromium Catalyst for Insight into Phillips-Type Ethylene Polymerization. MACROMOL REACT ENG 2018. [DOI: 10.1002/mren.201800049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yanning Zeng
- College of Materials Science and Engineering; Guilin University of Technology; Guilin 541004 China
| | - Shuxin Liu
- College of Materials Science and Engineering; Guilin University of Technology; Guilin 541004 China
| | - Minoru Terano
- Graduate School of Advanced Science and Technology; Japan Advanced Institute of Science and Technology; 1-1 Asahidai Nomi Ishikawa 923-1292 Japan
| |
Collapse
|
34
|
Copéret C, Allouche F, Chan KW, Conley MP, Delley MF, Fedorov A, Moroz IB, Mougel V, Pucino M, Searles K, Yamamoto K, Zhizhko PA. Bridging the Gap between Industrial and Well‐Defined Supported Catalysts. Angew Chem Int Ed Engl 2018; 57:6398-6440. [DOI: 10.1002/anie.201702387] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Florian Allouche
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Ka Wing Chan
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Matthew P. Conley
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
- Current address: Department of ChemistryUniversity of California, Riverside 501 Big Springs Road Riverside CA 92521 USA
| | - Murielle F. Delley
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Alexey Fedorov
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Ilia B. Moroz
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Victor Mougel
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
- Current address: Laboratoire de Chimie des Processus Biologiques, UMR CNRS 8229, Collège de FranceUniversité Pierre et Marie Curie 11 Place Marcelin Berthelot 75005 Paris France
| | - Margherita Pucino
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Keith Searles
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Keishi Yamamoto
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Pavel A. Zhizhko
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
- A. N. Nesmeyanov Institute of Organoelement CompoundsRussian Academy of Sciences Vavilov street 28 119991 Moscow Russia
| |
Collapse
|
35
|
Cook AK, Copéret C. Alkyne Hydroamination Catalyzed by Silica-Supported Isolated Zn(II) Sites. Organometallics 2018. [DOI: 10.1021/acs.organomet.8b00202] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Amanda K. Cook
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, CH-8093 Zürich, Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir Prelog Weg 1-5, CH-8093 Zürich, Switzerland
| |
Collapse
|
36
|
Copéret C, Allouche F, Chan KW, Conley MP, Delley MF, Fedorov A, Moroz IB, Mougel V, Pucino M, Searles K, Yamamoto K, Zhizhko PA. Eine Brücke zwischen industriellen und wohldefinierten Trägerkatalysatoren. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201702387] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Christophe Copéret
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Florian Allouche
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Ka Wing Chan
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Matthew P. Conley
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
- Department of ChemistryUniversity of California, Riverside 501 Big Springs Road Riverside CA 92521 USA
| | - Murielle F. Delley
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Alexey Fedorov
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Ilia B. Moroz
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Victor Mougel
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
- Laboratoire de Chimie des Processus Biologiques, UMR CNRS 8229, Collège de FranceUniversité Pierre et Marie Curie 11 Place Marcelin Berthelot 75005 Paris Frankreich
| | - Margherita Pucino
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Keith Searles
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Keishi Yamamoto
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
| | - Pavel A. Zhizhko
- Departement Chemie und Angewandte Biowissenschaften, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Schweiz
- A. N. Nesmeyanow-Institut für Elementorganische VerbindungenRussische Akademie der Wissenschaften Vavilov str. 28 119991 Moskau Russland
| |
Collapse
|
37
|
|
38
|
Docherty SR, Estes DP, Copéret C. Facile Synthesis of Unsymmetrical Trialkoxysilanols: (RO) 2
(R′O)SiOH. Helv Chim Acta 2018. [DOI: 10.1002/hlca.201700298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Scott R. Docherty
- Department of Chemistry and Applied Biology; ETH Zürich; Vladimir-Prelog-Weg 1-5 CH-8093 Zürich Switzerland
| | - Deven P. Estes
- Department of Chemistry and Applied Biology; ETH Zürich; Vladimir-Prelog-Weg 1-5 CH-8093 Zürich Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied Biology; ETH Zürich; Vladimir-Prelog-Weg 1-5 CH-8093 Zürich Switzerland
| |
Collapse
|
39
|
Allouche F, Chan KW, Fedorov A, Andersen RA, Copéret C. Silica-Supported Pentamethylcyclopentadienyl Ytterbium(II) and Samarium(II) Sites: Ultrahigh Molecular Weight Polyethylene without Co-Catalyst. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201800542] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Florian Allouche
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Ka Wing Chan
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Alexey Fedorov
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Richard A. Andersen
- Department of Chemistry; University of California; Berkeley CA 94720-1460 USA
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| |
Collapse
|
40
|
Allouche F, Chan KW, Fedorov A, Andersen RA, Copéret C. Silica-Supported Pentamethylcyclopentadienyl Ytterbium(II) and Samarium(II) Sites: Ultrahigh Molecular Weight Polyethylene without Co-Catalyst. Angew Chem Int Ed Engl 2018; 57:3431-3434. [DOI: 10.1002/anie.201800542] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Florian Allouche
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Ka Wing Chan
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Alexey Fedorov
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| | - Richard A. Andersen
- Department of Chemistry; University of California; Berkeley CA 94720-1460 USA
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences; ETH Zürich; Vladimir Prelog Weg 1-5 8093 Zürich Switzerland
| |
Collapse
|
41
|
Pacchioni G, Freund HJ. Controlling the charge state of supported nanoparticles in catalysis: lessons from model systems. Chem Soc Rev 2018; 47:8474-8502. [DOI: 10.1039/c8cs00152a] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Model systems are very important to identify the working principles of real catalysts, and to develop concepts that can be used in the design of new catalytic materials.
Collapse
Affiliation(s)
| | - Hans-Joachim Freund
- Fritz-Haber-Institut der Max-Planck-Gesellschaft
- Department of Chemical Physics
- 14195 Berlin
- Germany
| |
Collapse
|
42
|
Pan Q, Li L, Shaikhutdinov S, Freund HJ. Planar model system of the Phillips (Cr/SiO2) catalyst based on a well-defined thin silicate film. J Catal 2018. [DOI: 10.1016/j.jcat.2017.10.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
43
|
Martino GA, Barzan C, Piovano A, Budnyk A, Groppo E. Tracking the reasons for the peculiarity of Cr/Al2O3 catalyst in ethylene polymerization. J Catal 2018. [DOI: 10.1016/j.jcat.2017.11.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
44
|
Pan Q, Li L, Shaikhutdinov S, Fujimori Y, Hollerer M, Sterrer M, Freund HJ. Model systems in heterogeneous catalysis: towards the design and understanding of structure and electronic properties. Faraday Discuss 2018; 208:307-323. [DOI: 10.1039/c7fd00209b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We discuss in this paper two case studies related to nano-particle catalyst systems: one concerns a model system for the Cr/SiO2 Phillips catalyst for ethylene polymerization and the other provides additional information on Au nano-particles supported on ultrathin MgO(100)/Ag(100) films.
Collapse
Affiliation(s)
- Q. Pan
- Fritz-Haber-Institute of the Max-Planck Society
- Department of Chemical Physics
- 14195 Berlin
- Germany
| | - L. Li
- Fritz-Haber-Institute of the Max-Planck Society
- Department of Chemical Physics
- 14195 Berlin
- Germany
| | - S. Shaikhutdinov
- Fritz-Haber-Institute of the Max-Planck Society
- Department of Chemical Physics
- 14195 Berlin
- Germany
| | - Y. Fujimori
- Fritz-Haber-Institute of the Max-Planck Society
- Department of Chemical Physics
- 14195 Berlin
- Germany
| | - M. Hollerer
- University of Graz
- Institute of Physics
- NAWI Graz
- Universitätsplatz 5
- 8010 Graz
| | - M. Sterrer
- University of Graz
- Institute of Physics
- NAWI Graz
- Universitätsplatz 5
- 8010 Graz
| | - H.-J. Freund
- Fritz-Haber-Institute of the Max-Planck Society
- Department of Chemical Physics
- 14195 Berlin
- Germany
| |
Collapse
|
45
|
Olefin polymerization on Cr(III)/SiO2: Mechanistic insights from the differences in reactivity between ethene and propene. J Catal 2017. [DOI: 10.1016/j.jcat.2017.08.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
46
|
Brown C, Lita A, Tao Y, Peek N, Crosswhite M, Mileham M, Krzystek J, Achey R, Fu R, Bindra JK, Polinski M, Wang Y, van de Burgt LJ, Jeffcoat D, Profeta S, Stiegman AE, Scott SL. Mechanism of Initiation in the Phillips Ethylene Polymerization Catalyst: Ethylene Activation by Cr(II) and the Structure of the Resulting Active Site. ACS Catal 2017. [DOI: 10.1021/acscatal.7b02677] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Carole Brown
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Adrian Lita
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Yuchuan Tao
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Nathan Peek
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Mark Crosswhite
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Melissa Mileham
- Orbital ATK, Flight
Systems Group, Corinne, Utah 84307, United States
- Savannah River National Laboratory, Savannah River Site, Aiken, South Carolina 29808, United States
| | - J. Krzystek
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Randall Achey
- Savannah River National Laboratory, Savannah River Site, Aiken, South Carolina 29808, United States
| | - Riqiang Fu
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
| | - Jasleen K. Bindra
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Matthew Polinski
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Youhong Wang
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Lambertus J. van de Burgt
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - David Jeffcoat
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - Salvatore Profeta
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
| | - A. E. Stiegman
- Department
of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States
- National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Susannah L. Scott
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
47
|
Barzan C, Piovano A, Braglia L, Martino GA, Lamberti C, Bordiga S, Groppo E. Ligands Make the Difference! Molecular Insights into CrVI/SiO2 Phillips Catalyst during Ethylene Polymerization. J Am Chem Soc 2017; 139:17064-17073. [DOI: 10.1021/jacs.7b07437] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Caterina Barzan
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
| | - Alessandro Piovano
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
| | - Luca Braglia
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
- IRC
“Smart Materials”, Southern Federal University, Zorge
Street 5, Rostov-on-Don 344090, Russia
| | - Giorgia A. Martino
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
| | - Carlo Lamberti
- IRC
“Smart Materials”, Southern Federal University, Zorge
Street 5, Rostov-on-Don 344090, Russia
- Department
of Chemistry, CrisDi Interdepartmental Center, University of Turin, Via P. Giuria 7, Turin I10125, Italy
| | - Silvia Bordiga
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
| | - Elena Groppo
- Department
of Chemistry, NIS Interdepartmental Center and INSTM Reference Center, University of Turin, Via G. Quarello 15A, Turin I10135, Italy
| |
Collapse
|
48
|
Active sites formation and their transformations during ethylene polymerization by the Phillips CrOx/SiO2 catalyst. J Catal 2017. [DOI: 10.1016/j.jcat.2017.05.025] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
49
|
Sun Q, Cheng R, Liu Z, He X, Zhao N, Liu B. Effect of Fluoride-Modification on the Phillips Cr/SiO2
Catalyst for Ethylene Polymerization. ChemCatChem 2017. [DOI: 10.1002/cctc.201700375] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Qiaoqiao Sun
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road 200237 Shanghai P.R. China
| | - Ruihua Cheng
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road 200237 Shanghai P.R. China
| | - Zhen Liu
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road 200237 Shanghai P.R. China
| | - Xuelian He
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road 200237 Shanghai P.R. China
| | - Ning Zhao
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road 200237 Shanghai P.R. China
| | - Boping Liu
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; 130 Meilong Road, 200237 Shanghai P.R. China
| |
Collapse
|
50
|
Copéret C, Fedorov A, Zhizhko PA. Surface Organometallic Chemistry: Paving the Way Beyond Well-Defined Supported Organometallics and Single-Site Catalysis. Catal Letters 2017. [DOI: 10.1007/s10562-017-2107-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|