1
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Heyer AJ, Ma J, Plessers D, Braun A, Bols ML, Rhoda HM, Schoonheydt RA, Sels BF, Solomon EI. Spectroscopic Investigation of the Role of Water in Copper Zeolite Methane Oxidation. J Am Chem Soc 2024; 146:21208-21213. [PMID: 39046226 DOI: 10.1021/jacs.4c06010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
Methane is one of the most potent greenhouse gases; developing technology for its abatement is essential for combating climate change. Copper zeolites can activate methane at low temperatures and pressures, demonstrating promise for this technology. However, a barrier to industrial implementation is the inability to recycle the Cu(II) active site. Anaerobic active site regeneration has been reported for copper-loaded mordenite, where it is proposed that water oxidizes Cu(I) formed from the methane reaction, producing H2 gas as a byproduct. However, this result has been met with skepticism given the overall reaction is thermodynamically unfavorable. In this study, we use X-ray absorption and electron paramagnetic resonance spectroscopies to study the role of water in copper zeolite methane oxidation. We find that water does not oxidize Cu(I) to Cu(II) in CH4-reacted Cu-MOR. Further, using isotope label mass spectrometry, we detail an alternate source of the hydrogen byproduct. We uncover that, although water does not oxidize Cu(I), it has the potential to facilitate low temperature methane abatement through promotion of product decomposition to carbon dioxide and H2.
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Affiliation(s)
- Alexander J Heyer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Jing Ma
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Dieter Plessers
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Augustin Braun
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Max L Bols
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Hannah M Rhoda
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Robert A Schoonheydt
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Bert F Sels
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, Leuven B-3001, Belgium
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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2
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De Tovar J, Leblay R, Wang Y, Wojcik L, Thibon-Pourret A, Réglier M, Simaan AJ, Le Poul N, Belle C. Copper-oxygen adducts: new trends in characterization and properties towards C-H activation. Chem Sci 2024; 15:10308-10349. [PMID: 38994420 PMCID: PMC11234856 DOI: 10.1039/d4sc01762e] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 05/11/2024] [Indexed: 07/13/2024] Open
Abstract
This review summarizes the latest discoveries in the field of C-H activation by copper monoxygenases and more particularly by their bioinspired systems. This work first describes the recent background on copper-containing enzymes along with additional interpretations about the nature of the active copper-oxygen intermediates. It then focuses on relevant examples of bioinorganic synthetic copper-oxygen intermediates according to their nuclearity (mono to polynuclear). This includes a detailed description of the spectroscopic features of these adducts as well as their reactivity towards the oxidation of recalcitrant Csp3 -H bonds. The last part is devoted to the significant expansion of heterogeneous catalytic systems based on copper-oxygen cores (i.e. within zeolite frameworks).
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Affiliation(s)
- Jonathan De Tovar
- Université Grenoble-Alpes, CNRS, Département de Chimie Moléculaire Grenoble France
| | - Rébecca Leblay
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Institut des Sciences Moléculaires de Marseille Marseille France
| | - Yongxing Wang
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Institut des Sciences Moléculaires de Marseille Marseille France
| | - Laurianne Wojcik
- Université de Brest, Laboratoire de Chimie, Electrochimie Moléculaires et Chimie Analytique Brest France
| | | | - Marius Réglier
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Institut des Sciences Moléculaires de Marseille Marseille France
| | - A Jalila Simaan
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Institut des Sciences Moléculaires de Marseille Marseille France
| | - Nicolas Le Poul
- Université de Brest, Laboratoire de Chimie, Electrochimie Moléculaires et Chimie Analytique Brest France
| | - Catherine Belle
- Université Grenoble-Alpes, CNRS, Département de Chimie Moléculaire Grenoble France
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3
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Wijerathne A, Sawyer A, Daya R, Paolucci C. Competition between Mononuclear and Binuclear Copper Sites across Different Zeolite Topologies. JACS AU 2024; 4:197-215. [PMID: 38274255 PMCID: PMC10806779 DOI: 10.1021/jacsau.3c00632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 01/27/2024]
Abstract
A key challenge for metal-exchanged zeolites is the determination of metal cation speciation and nuclearity under synthesis and reaction conditions. Copper-exchanged zeolites, which are widely used in automotive emissions control and potential catalysts for partial methane oxidation, have in particular evidenced a wide variety of Cu structures that are observed to change with exposure conditions, zeolite composition, and topology. Here, we develop predictive models for Cu cation speciation and nuclearity in CHA, MOR, BEA, AFX, and FER zeolite topologies using interatomic potentials, quantum chemical calculations, and Monte Carlo simulations to interrogate this vast configurational and compositional space. Model predictions are used to rationalize experimentally observed differences between Cu-zeolites in a wide-body of literature, including nuclearity populations, structural variations, and methanol per Cu yields. Our results show that both topological features and commonly observed Al-siting biases in MOR zeolites increase the population of binuclear Cu sites, explaining the small population of mononuclear Cu sites observed in these materials relative to other zeolites such as CHA and BEA. Finally, we used a machine learning classification model to determine the preference to form mononuclear or binuclear Cu sites at different Al configurations in 200 zeolites in the international zeolite database. Model results reveal several zeolite topologies at extreme ends of the mononuclear vs binuclear spectrum, highlighting synthetic options for realization of zeolites with strong Cu nuclearity preferences.
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Affiliation(s)
- Asanka Wijerathne
- Department
of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Allison Sawyer
- Department
of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Rohil Daya
- Cummins
Inc, Columbus, Indiana 47201, United States
| | - Christopher Paolucci
- Department
of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903, United States
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4
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Artsiusheuski MA, Verel R, van Bokhoven JA, Sushkevich VL. Selective Oxidative Dehydrogenation of Ethane and Propane over Copper-Containing Mordenite: Insights into Reaction Mechanism and Product Protection. Angew Chem Int Ed Engl 2023; 62:e202309180. [PMID: 37699126 DOI: 10.1002/anie.202309180] [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: 06/29/2023] [Revised: 09/07/2023] [Accepted: 09/11/2023] [Indexed: 09/14/2023]
Abstract
Copper(II)-containing mordenite (CuMOR) is capable of activation of C-H bonds in C1 -C3 alkanes, albeit there are remarkable differences between the functionalization of ethane and propane compared to methane. The reaction of ethane and propane with CuMOR results in the formation of ethylene and propylene, while the reaction of methane predominantly yields methanol and dimethyl ether. By combining in situ FTIR and MAS NMR spectroscopies as well as time-resolved Cu K-edge X-ray absorption spectroscopy, the reaction mechanism was derived, which differs significantly for each alkane. The formation of ethylene and propylene proceeds via oxidative dehydrogenation of the corresponding alkanes with selectivity above 95 % for ethane and above 85 % for propane. The formation of stable π-complexes of olefins with CuI sites, formed upon reduction of CuII -oxo species, protects olefins from further oxidation and/or oligomerization. This is different from methane, the activation of which proceeds via oxidative hydroxylation leading to the formation of surface methoxy species bonded to the zeolite framework. Our findings constitute one of the major steps in the direct conversion of alkanes to important commodities and open a novel research direction aiming at the selective synthesis of olefins.
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Affiliation(s)
- Mikalai A Artsiusheuski
- Institute for Chemistry and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093, Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - René Verel
- Institute for Chemistry and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093, Zurich, Switzerland
| | - Jeroen A van Bokhoven
- Institute for Chemistry and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093, Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
| | - Vitaly L Sushkevich
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232, Villigen PSI, Switzerland
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5
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Kvande K, Garetto B, Deplano G, Signorile M, Solemsli BG, Prodinger S, Olsbye U, Beato P, Bordiga S, Svelle S, Borfecchia E. Understanding C-H activation in light alkanes over Cu-MOR zeolites by coupling advanced spectroscopy and temperature-programmed reduction experiments. Chem Sci 2023; 14:9704-9723. [PMID: 37736625 PMCID: PMC10510758 DOI: 10.1039/d3sc01677c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 08/19/2023] [Indexed: 09/23/2023] Open
Abstract
The direct activation of methane to methanol (MTM) proceeds through a chemical-looping process over Cu-oxo sites in zeolites. Herein, we extend the overall understanding of oxidation reactions over metal-oxo sites and C-H activation reactions by pinpointing the evolution of Cu species during reduction. To do so, a set of temperature-programmed reduction experiments were performed with CH4, C2H6, and CO. With a temperature ramp, the Cu reduction could be accelerated to detect changes in Cu speciation that are normally not detected due to the slow CH4 adsorption/interaction during MTM (∼200 °C). To follow the Cu-speciation with the three reductants, X-ray absorption spectroscopy (XAS), UV-vis and FT-IR spectroscopy were applied. Multivariate curve resolution alternating least-square (MCR-ALS) analysis was used to resolve the time-dependent concentration profiles of pure Cu components in the X-ray absorption near edge structure (XANES) spectra. Within the large datasets, as many as six different CuII and CuI components were found. Close correlations were found between the XANES-derived CuII to CuI reduction, CH4 consumption, and CO2 production. A reducibility-activity relationship was also observed for the Cu-MOR zeolites. Extended X-ray absorption fine structure (EXAFS) spectra for the pure Cu components were furthermore obtained with MCR-ALS analysis. With wavelet transform (WT) analysis of the EXAFS spectra, we were able to resolve the atomic speciation at different radial distances from Cu (up to about 4 Å). These results indicate that all the CuII components consist of multimeric CuII-oxo sites, albeit with different Cu-Cu distances.
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Affiliation(s)
- Karoline Kvande
- Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo 1033 Blindern 0315 Oslo Norway
| | - Beatrice Garetto
- Department of Chemistry, NIS Center and INSTM Reference Center, University of Turin, 10125 Turin Via P. Giuria 7 Italy
| | - Gabriele Deplano
- Department of Chemistry, NIS Center and INSTM Reference Center, University of Turin, 10125 Turin Via P. Giuria 7 Italy
| | - Matteo Signorile
- Department of Chemistry, NIS Center and INSTM Reference Center, University of Turin, 10125 Turin Via P. Giuria 7 Italy
| | - Bjørn Gading Solemsli
- Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo 1033 Blindern 0315 Oslo Norway
| | - Sebastian Prodinger
- Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo 1033 Blindern 0315 Oslo Norway
| | - Unni Olsbye
- Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo 1033 Blindern 0315 Oslo Norway
| | - Pablo Beato
- Topsoe A/S, Haldor Topsøes Allé 1 DK-2800 Kgs. Lyngby Denmark
| | - Silvia Bordiga
- Department of Chemistry, NIS Center and INSTM Reference Center, University of Turin, 10125 Turin Via P. Giuria 7 Italy
| | - Stian Svelle
- Centre for Materials Science and Nanotechnology (SMN), Department of Chemistry, University of Oslo 1033 Blindern 0315 Oslo Norway
| | - Elisa Borfecchia
- Department of Chemistry, NIS Center and INSTM Reference Center, University of Turin, 10125 Turin Via P. Giuria 7 Italy
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6
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Lei H, Chen D, Yang JY, Khetan A, Jiang J, Peng B, Simon U, Ye D, Chen P. Revealing the Formation and Reactivity of Cage-Confined Cu Pairs in Catalytic NO x Reduction over Cu-SSZ-13 Zeolites by In Situ UV-Vis Spectroscopy and Time-Dependent DFT Calculation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12465-12475. [PMID: 37556316 DOI: 10.1021/acs.est.3c00458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
The low-temperature mechanism of chabazite-type small-pore Cu-SSZ-13 zeolite, a state-of-the-art catalyst for ammonia-assisted selective reduction (NH3-SCR) of toxic NOx pollutants from heavy-duty vehicles, remains a debate and needs to be clarified for further improvement of NH3-SCR performance. In this study, we established experimental protocols to follow the dynamic redox cycling (i.e., CuII ↔ CuI) of Cu sites in Cu-SSZ-13 during low-temperature NH3-SCR catalysis by in situ ultraviolet-visible spectroscopy and in situ infrared spectroscopy. Further integrating the in situ spectroscopic observations with time-dependent density functional theory calculations allows us to identify two cage-confined transient states, namely, the O2-bridged Cu dimers (i.e., μ-η2:η2-peroxodiamino dicopper) and the proximately paired, chemically nonbonded CuI(NH3)2 sites, and to confirm the CuI(NH3)2 pair as a precursor to the O2-bridged Cu dimer. Comparative transient experiments reveal a particularly high reactivity of the CuI(NH3)2 pairs for NO-to-N2 reduction at low temperatures. Our study demonstrates direct experimental evidence for the transient formation and high reactivity of proximately paired CuI sites under zeolite confinement and provides new insights into the monomeric-to-dimeric Cu transformation for completing the Cu redox cycle in low-temperature NH3-SCR catalysis over Cu-SSZ-13.
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Affiliation(s)
- Huarong Lei
- Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, National Engineering Laboratory for VOCs Pollution Control Technology and Equipment, School of Environment and Energy, South China University of Technology, 510006 Guangzhou, China
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
| | - Dongdong Chen
- Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, National Engineering Laboratory for VOCs Pollution Control Technology and Equipment, School of Environment and Energy, South China University of Technology, 510006 Guangzhou, China
| | - Jia-Yue Yang
- Optics & Thermal Radiation Research Center, Shandong University, Qingdao 266237 China
| | - Abhishek Khetan
- Fuel Science Center, RWTH Aachen University, Schinkelstr. 8, 52074 Aachen, Germany
| | - Jiuxing Jiang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275 China
| | - Baoxiang Peng
- Laboratory of Industrial Chemistry, Ruhr-University Bochum, Universitätsstr. 150, Bochum 44780 Germany
| | - Ulrich Simon
- Institute of Inorganic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany
- Fuel Science Center, RWTH Aachen University, Schinkelstr. 8, 52074 Aachen, Germany
| | - Daiqi Ye
- Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, National Engineering Laboratory for VOCs Pollution Control Technology and Equipment, School of Environment and Energy, South China University of Technology, 510006 Guangzhou, China
| | - Peirong Chen
- Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, National Engineering Laboratory for VOCs Pollution Control Technology and Equipment, School of Environment and Energy, South China University of Technology, 510006 Guangzhou, China
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7
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Fischer JWA, Brenig A, Klose D, van Bokhoven JA, Sushkevich VL, Jeschke G. Methane Oxidation over Cu 2+ /[CuOH] + Pairs and Site-Specific Kinetics in Copper Mordenite Revealed by Operando Electron Paramagnetic Resonance and UV/Visible Spectroscopy. Angew Chem Int Ed Engl 2023; 62:e202303574. [PMID: 37292054 DOI: 10.1002/anie.202303574] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/10/2023]
Abstract
Cu-exchanged mordenite (MOR) is a promising material for partial CH4 oxidation. The structural diversity of Cu species within MOR makes it difficult to identify the active Cu sites and to determine their redox and kinetic properties. In this study, the Cu speciation in Cu-MOR materials with different Cu loadings has been determined using operando electron paramagnetic resonance (EPR) and operando ultraviolet-visible (UV/Vis) spectroscopy as well as in situ photoluminescence (PL) and Fourier-transform infrared (FTIR) spectroscopy. A novel pathway for CH4 oxidation involving paired [CuOH]+ and bare Cu2+ species has been identified. The reduction of bare Cu2+ ions facilitated by adjacent [CuOH]+ demonstrates that the frequently reported assumption of redox-inert Cu2+ centers does not generally apply. The measured site-specific reaction kinetics show that dimeric Cu species exhibit a faster reaction rate and a higher apparent activation energy than monomeric Cu2+ active sites highlighting their difference in the CH4 oxidation potential.
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Affiliation(s)
| | - Andreas Brenig
- Institute for Chemical and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen, Switzerland
| | - Daniel Klose
- Institute for Molecular Physical Science, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
| | - Jeroen Anton van Bokhoven
- Institute for Chemical and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen, Switzerland
| | - Vitaly L Sushkevich
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, Forschungsstrasse 111, 5232, Villigen, Switzerland
| | - Gunnar Jeschke
- Institute for Molecular Physical Science, ETH Zurich, Vladimir-Prelog-Weg 1-5/10, 8093, Zurich, Switzerland
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8
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Tang X, Ye J, Guo L, Pu T, Cheng L, Cao XM, Guo Y, Wang L, Guo Y, Zhan W, Dai S. Atomic Insights into the Cu Species Supported on Zeolite for Direct Oxidation of Methane to Methanol via Low-Damage HAADF-STEM. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023:e2208504. [PMID: 37014632 DOI: 10.1002/adma.202208504] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 02/04/2023] [Indexed: 06/19/2023]
Abstract
Precise determination of the structure-property relationship of zeolite-based metal catalysts is critical for the development toward practical applications. However, the scarcity of real-space imaging of zeolite-based low-atomic-number (LAN) metal materials due to the electron-beam sensitivity of zeolites has led to continuous debates regarding the exact LAN metal configurations. Here, a low-damage high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging technique is employed for direct visualization and determination of LAN metal (Cu) species in ZSM-5 zeolite frameworks. The structures of the Cu species are revealed based on the microscopy evidence and also proved by the complementary spectroscopy results. The correlation between the characteristic Cu size in Cu/ZSM-5 catalysts and their direct oxidation of methane to methanol reaction properties is unveiled. As a result, the mono-Cu species stably anchored by Al pairs inside the zeolite channels are identified as the key structure for higher C1 oxygenates yield and methanol selectivity for direct oxidation of methane. Meanwhile, the local topological flexibility of the rigid zeolite frameworks induced by the Cu agglomeration in the channels is also revealed. This work exemplifies the combination of microscopy imaging and spectroscopy characterization serves as a complete arsenal for revealing structure-property relationships of the supported metal-zeolite catalysts.
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Affiliation(s)
- Xuan Tang
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Jiajie Ye
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Lisheng Guo
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
| | - Tiancheng Pu
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, Pennsylvania, 18015, United States
| | - Lu Cheng
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Xiao-Ming Cao
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Yanglong Guo
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Li Wang
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Yun Guo
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Wangcheng Zhan
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
| | - Sheng Dai
- Key Laboratory for Advanced Materials, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, P. R. China
- Key Laboratory for Advanced Materials, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, P. R. China
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9
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Zhang X, Liu R, Liu T, Pei C, Gong J. Redox catalysts for chemical looping methane conversion. TRENDS IN CHEMISTRY 2023. [DOI: 10.1016/j.trechm.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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10
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Pokhrel J, Shantz DF. Continuous Partial Oxidation of Methane to Methanol over Cu-SSZ-39 catalysts. J Catal 2023. [DOI: 10.1016/j.jcat.2023.03.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023]
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11
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Plessers D, Heyer AJ, Rhoda HM, Bols ML, Solomon EI, Schoonheydt RA, Sels BF. Tuning Copper Active Site Composition in Cu-MOR through Co-Cation Modification for Methane Activation. ACS Catal 2023. [DOI: 10.1021/acscatal.2c05271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Dieter Plessers
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, B-3001Leuven, Belgium
| | - Alexander J. Heyer
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Hannah M. Rhoda
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Max L. Bols
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, B-3001Leuven, Belgium
| | - Edward I. Solomon
- Department of Chemistry, Stanford University, Stanford, California94305, United States
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
| | - Robert A. Schoonheydt
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, B-3001Leuven, Belgium
| | - Bert F. Sels
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, B-3001Leuven, Belgium
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12
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Copper-zeolites Prepared by Solid-state Ion Exchange - Characterization and Evaluation for the Direct Conversion of Methane to Methanol. Top Catal 2022. [DOI: 10.1007/s11244-022-01763-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
AbstractDirect conversion of methane to methanol (MTM) over Cu-zeolites is a so-called “dream reaction” for the chemical industry. There is still a lot that can be done in order to optimize the reaction by e.g. achieving a deeper understanding of the reaction mechanism and the nature of the Cu-sites. In this study, we investigated a solid-state ion exchange method to incorporate CuI ions into zeolites (MOR, BEA, ZSM-5 and FAU), as a more scalable technique. The solid-state ion exchange led to a Cu/Al ration of about 0.8, however with a heterogeneous distribution of Cu. Regardless, Fourier transform-infrared spectroscopy still revealed that most Brønsted acid sites were exchanged in all four samples. Further, CH4-temperature programmed reaction experiments showed that some Cu-sites formed were reactive towards CH4, with CuI-MOR and CuI-FAU having the largest CH4 consumption. Ultimately, the CuI-zeolites were tested in the MTM reaction and proved capable of producing methanol, even without the presence of Brønsted sites. A MOR with lower Cu/Al ratio (0.30) was also tested for comparison, and as this sample obtained a much higher productivity than the CuI-MOR with high Cu-loading (0.10 vs. 0.03 molMeOH/molCu), it was demonstrated that some fine-tuning is necessary to obtain the active Cu sites for methane activation.
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Artsiusheuski MA, van Bokhoven JA, Sushkevich VL. Structure of Selective and Nonselective Dicopper (II) Sites in CuMFI for Methane Oxidation to Methanol. ACS Catal 2022. [DOI: 10.1021/acscatal.2c05299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mikalai A. Artsiusheuski
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232Villigen PSI, Switzerland
- Institute for Chemistry and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093Zurich, Switzerland
| | - Jeroen A. van Bokhoven
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232Villigen PSI, Switzerland
- Institute for Chemistry and Bioengineering, ETH Zurich, Vladimir-Prelog-Weg 1, 8093Zurich, Switzerland
| | - Vitaly L. Sushkevich
- Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institut, 5232Villigen PSI, Switzerland
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Heyer AJ, Plessers D, Braun A, Rhoda HM, Bols ML, Hedman B, Hodgson KO, Schoonheydt RA, Sels BF, Solomon EI. Methane Activation by a Mononuclear Copper Active Site in the Zeolite Mordenite: Effect of Metal Nuclearity on Reactivity. J Am Chem Soc 2022; 144:19305-19316. [PMID: 36219763 DOI: 10.1021/jacs.2c06269] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The direct conversion of methane to methanol would have a wide reaching environmental and industrial impact. Copper-containing zeolites can perform this reaction at low temperatures and pressures at a previously defined O2-activated [Cu2O]2+ site. However, after autoreduction of the copper-containing zeolite mordenite and removal of the [Cu2O]2+ active site, the zeolite is still methane reactive. In this study, we use diffuse reflectance UV-vis spectroscopy, magnetic circular dichroism, resonance Raman spectroscopy, electron paramagnetic resonance, and X-ray absorption spectroscopy to unambiguously define a mononuclear [CuOH]+ as the CH4 reactive active site of the autoreduced zeolite. The rigorous identification of a mononuclear active site allows a reactivity comparison to the previously defined [Cu2O]2+ active site. We perform kinetic experiments to compare the reactivity of the [CuOH]+ and [Cu2O]2+ sites and find that the binuclear site is significantly more reactive. From the analysis of density functional theory calculations, we elucidate that this increased reactivity is a direct result of stabilization of the [Cu2OH]2+ H-atom abstraction product by electron delocalization over the two Cu cations via the bridging ligand. This significant increase in reactivity from electron delocalization over a binuclear active site provides new insights for the design of highly reactive oxidative catalysts.
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Affiliation(s)
- Alexander J Heyer
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Dieter Plessers
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Augustin Braun
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Hannah M Rhoda
- Department of Chemistry, Stanford University, Stanford, California94305, United States
| | - Max L Bols
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Britt Hedman
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
| | - Keith O Hodgson
- Department of Chemistry, Stanford University, Stanford, California94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
| | - Robert A Schoonheydt
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Bert F Sels
- Department of Microbial and Molecular Systems, Center for Sustainable Catalysis and Engineering, KU Leuven-University of Leuven, LeuvenB-3001, Belgium
| | - Edward I Solomon
- Department of Chemistry, Stanford University, Stanford, California94305, United States.,Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California94025, United States
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15
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Signorile M, Borfecchia E, Bordiga S, Berlier G. Influence of ion mobility on the redox and catalytic properties of Cu ions in zeolites. Chem Sci 2022; 13:10238-10250. [PMID: 36277636 PMCID: PMC9473501 DOI: 10.1039/d2sc03565k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 08/15/2022] [Indexed: 01/09/2023] Open
Abstract
This contribution aims at analysing the current understanding about the influence of Al distribution, zeolite topology, ligands/reagents and oxidation state on ions mobility in Cu-zeolites, and its relevance toward reactivity of the metal sites. The concept of Cu mobilization has been originally observed in the presence of ammonia, favouring the activation of oxygen by formation of NH3 oxo-bridged complexes in zeolites and opening a new perspective about the chemistry in single-site zeolite-based catalysts, in particular in the context of the NH3-mediated Selective Catalytic Reduction of NO x (NH3-SCR) processes. A different mobility of bare Cu+/Cu2+ ions has been documented too, showing for Cu+ a better mobilization than for Cu2+ also in absence of ligands. These concepts can have important consequences for the formation of Cu-oxo species, active and selective in other relevant reactions, such as the direct conversion of methane to methanol. Here, assessing the structure, the formation pathways and reactivity of Cu-oxo mono- or multimeric moieties still represents a challenging playground for chemical scientists. Translating the knowledge about Cu ions mobility and redox properties acquired in the context of NH3-SCR reaction into the field of direct conversion of methane to methanol can have important implications for a better understanding of transition metal ions redox properties in zeolites and for an improved design of catalysts and catalytic processes.
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Affiliation(s)
- Matteo Signorile
- Department of Chemistry and NIS Centre, Università di Torino Via P. Giuria 7 Torino 10125 Italy
| | - Elisa Borfecchia
- Department of Chemistry and NIS Centre, Università di Torino Via P. Giuria 7 Torino 10125 Italy
| | - Silvia Bordiga
- Department of Chemistry and NIS Centre, Università di Torino Via P. Giuria 7 Torino 10125 Italy
| | - Gloria Berlier
- Department of Chemistry and NIS Centre, Università di Torino Via P. Giuria 7 Torino 10125 Italy
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Kumar P, Al-Attas TA, Hu J, Kibria MG. Single Atom Catalysts for Selective Methane Oxidation to Oxygenates. ACS NANO 2022; 16:8557-8618. [PMID: 35638813 DOI: 10.1021/acsnano.2c02464] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Direct conversion of methane (CH4) to C1-2 liquid oxygenates is a captivating approach to lock carbons in transportable value-added chemicals, while reducing global warming. Existing approaches utilizing the transformation of CH4 to liquid fuel via tandemized steam methane reforming and the Fischer-Tropsch synthesis are energy and capital intensive. Chemocatalytic partial oxidation of methane remains challenging due to the negligible electron affinity, poor C-H bond polarizability, and high activation energy barrier. Transition-metal and stoichiometric catalysts utilizing harsh oxidants and reaction conditions perform poorly with randomized product distribution. Paradoxically, the catalysts which are active enough to break C-H also promote overoxidation, resulting in CO2 generation and reduced carbon balance. Developing catalysts which can break C-H bonds of methane to selectively make useful chemicals at mild conditions is vital to commercialization. Single atom catalysts (SACs) with specifically coordinated metal centers on active support have displayed intrigued reactivity and selectivity for methane oxidation. SACs can significantly reduce the activation energy due to induced electrostatic polarization of the C-H bond to facilitate the accelerated reaction rate at the low reaction temperature. The distinct metal-support interaction can stabilize the intermediate and prevent the overoxidation of the reaction products. The present review accounts for recent progress in the field of SACs for the selective oxidation of CH4 to C1-2 oxygenates. The chemical nature of catalytic sites, effects of metal-support interaction, and stabilization of intermediate species on catalysts to minimize overoxidation are thoroughly discussed with a forward-looking perspective to improve the catalytic performance.
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Affiliation(s)
- Pawan Kumar
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Tareq A Al-Attas
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Jinguang Hu
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
| | - Md Golam Kibria
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
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van Vreeswijk SH, Weckhuysen BM. Emerging Analytical Methods to Characterize Zeolite-Based Materials. Natl Sci Rev 2022; 9:nwac047. [PMID: 36128456 PMCID: PMC9477204 DOI: 10.1093/nsr/nwac047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Revised: 02/23/2022] [Accepted: 02/28/2022] [Indexed: 11/23/2022] Open
Abstract
Zeolites and zeolitic materials are, through their use in numerous conventional and sustainable applications, very important to our daily lives, including to foster the necessary transition to a more circular society. The characterization of zeolite-based materials has a tremendous history and a great number of applications and properties of these materials have been discovered in the past decades. This review focuses on recently developed novel as well as more conventional techniques applied with the aim of better understanding zeolite-based materials. Recently explored analytical methods, e.g. atom probe tomography, scanning transmission X-ray microscopy, confocal fluorescence microscopy and photo-induced force microscopy, are discussed on their important contributions to the better understanding of zeolites as they mainly focus on the micro- to nanoscale chemical imaging and the revelation of structure–composition–performance relationships. Some other techniques have a long and established history, e.g. nuclear magnetic resonance, infrared, neutron scattering, electron microscopy and X-ray diffraction techniques, and have gone through increasing developments allowing the techniques to discover new and important features in zeolite-based materials. Additional to the increasing application of these methods, multiple techniques are nowadays used to study zeolites under working conditions (i.e. the in situ/operando mode of analysis) providing new insights in reaction and deactivation mechanisms.
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Affiliation(s)
- S H van Vreeswijk
- Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - B M Weckhuysen
- Inorganic Chemistry and Catalysis, Debye Institute for Nanomaterials, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
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18
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Abstract
Methane is an abundant resource and its direct conversion into value-added chemicals has been an attractive subject for its efficient utilization. This method can be more efficient than the present energy-intensive indirect conversion of methane via syngas, a mixture of CO and H2. Among the various approaches for direct methane conversion, the selective oxidation of methane into methane oxygenates (e.g., methanol and formaldehyde) is particularly promising because it can proceed at low temperatures. Nevertheless, due to low product yields this method is challenging. Compared with the liquid-phase partial oxidation of methane, which frequently demands for strong oxidizing agents in protic solvents, gas-phase selective methane oxidation has some merits, such as the possibility of using oxygen as an oxidant and the ease of scale-up owing to the use of heterogeneous catalysts. Herein, we summarize recent advances in the gas-phase partial oxidation of methane into methane oxygenates, focusing mainly on its conversion into formaldehyde and methanol.
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Mahyuddin MH, Saputro AG, Sukanli RPP, Fathurrahman F, Rizkiana J, Nuruddin A, Dipojono HK. Molecular insight into the role of zeolite lattice constraints on methane activation over the Cu-O-Cu active site. Phys Chem Chem Phys 2022; 24:4196-4203. [PMID: 35119442 DOI: 10.1039/d1cp05371j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Understanding the factors that influence the activity of a catalyst toward CH4 activation is of high importance for tuning the catalyst performance or designing new, better catalysts. Here, we performed a set of density functional theory (DFT) calculations on the H-CH3 bond cleavage over the Cu-O-Cu active site in the MOR zeolite with various Al-pair arrangements to obtain molecular insight into the structure-activity relation and clarify key parameters that define the Cu-O-Cu reactivity toward CH4. We found that weakening of the Cu-O-Cu bond during CH4 activation is crucial for determining the O-H bond strength and thus the Cu-O-Cu reactivity. In this regard, the zeolite lattice constraints are found to play a significant role as, on the one hand, it strengthens the Cu⋯Cu interaction and consequently weakens the Cu-O-Cu bonds and, on the other hand, it forces the Cu-O-Cu bond elongation process to destabilize the active site structure. The non-planar Cu-O-Cu geometry, due to lattice constraints, is also found to make the CH4 adsorption site, whether positioned closer to the μ-O or the Cu atom, crucial in determining the C-H activation product, i.e., a ˙CH3 radical or a Cu2-CH3- ligand.
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Affiliation(s)
- Muhammad Haris Mahyuddin
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia. .,Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
| | - Adhitya Gandaryus Saputro
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia. .,Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
| | - Reza Pamungkas Putra Sukanli
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia.
| | - Fadjar Fathurrahman
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia. .,Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
| | - Jenny Rizkiana
- Department of Chemical Engineering, Faculty of Industrial Technology, Institut Teknologi Bandung, Ganesha 10, Bandung 40132, Indonesia
| | - Ahmad Nuruddin
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia.
| | - Hermawan Kresno Dipojono
- Research Group of Advanced Functional Materials, Faculty of Industrial Technology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia. .,Research Center for Nanoscience and Nanotechnology, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia
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20
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Wilcox LN, Krishna SH, Jones CB, Gounder R. Mechanistic studies of NH 3-assisted reduction of mononuclear Cu( ii) cation sites in Cu-CHA zeolites. Catal Sci Technol 2021. [DOI: 10.1039/d1cy01646f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Spectroscopic, titrimetric, and gas-phase product analysis methods reveal a six-electron process for NH3-assisted reduction of mononuclear Cu(ii) sites to Cu(i) in Cu-CHA zeolites of different Cu(ii) site speciation and density.
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Affiliation(s)
- Laura N. Wilcox
- Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Siddarth H. Krishna
- Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Casey B. Jones
- Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - Rajamani Gounder
- Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, 47907, USA
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