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Pastor E, Lian Z, Xia L, Ecija D, Galán-Mascarós JR, Barja S, Giménez S, Arbiol J, López N, García de Arquer FP. Complementary probes for the electrochemical interface. Nat Rev Chem 2024; 8:159-178. [PMID: 38388837 DOI: 10.1038/s41570-024-00575-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2024] [Indexed: 02/24/2024]
Abstract
The functions of electrochemical energy conversion and storage devices rely on the dynamic junction between a solid and a fluid: the electrochemical interface (EI). Many experimental techniques have been developed to probe the EI, but they provide only a partial picture. Building a full mechanistic understanding requires combining multiple probes, either successively or simultaneously. However, such combinations lead to important technical and theoretical challenges. In this Review, we focus on complementary optoelectronic probes and modelling to address the EI across different timescales and spatial scales - including mapping surface reconstruction, reactants and reaction modulators during operation. We discuss how combining these probes can facilitate a predictive design of the EI when closely integrated with theory.
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Affiliation(s)
- Ernest Pastor
- CNRS, IPR (Institut de Physique de Rennes), University of Rennes, Rennes, France.
- CNRS, Univ Rennes, DYNACOM (Dynamical Control of Materials Laboratory) - IRL2015, The University of Tokyo, Tokyo, Japan.
| | - Zan Lian
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
| | - Lu Xia
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - David Ecija
- IMDEA Nanoscience, Campus Universitario de Cantoblanco, Madrid, Spain
| | - José Ramón Galán-Mascarós
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
- ICREA, Barcelona, Spain
| | - Sara Barja
- Department of Polymers and Advanced Materials, Centro de Física de Materiales (CFM), University of the Basque Country UPV/EHU, San Sebastián, Spain
- Donostia International Physics Center (DIPC), San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Sixto Giménez
- Institute of Advanced Materials (INAM) Universitat Jaume I, Castelló, Spain
| | - Jordi Arbiol
- ICREA, Barcelona, Spain
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Catalonia, Spain
| | - Núria López
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
| | - F Pelayo García de Arquer
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain.
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Omori NE, Bobitan AD, Vamvakeros A, Beale AM, Jacques SDM. Recent developments in X-ray diffraction/scattering computed tomography for materials science. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2023; 381:20220350. [PMID: 37691470 PMCID: PMC10493554 DOI: 10.1098/rsta.2022.0350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 07/17/2023] [Indexed: 09/12/2023]
Abstract
X-ray diffraction/scattering computed tomography (XDS-CT) methods are a non-destructive class of chemical imaging techniques that have the capacity to provide reconstructions of sample cross-sections with spatially resolved chemical information. While X-ray diffraction CT (XRD-CT) is the most well-established method, recent advances in instrumentation and data reconstruction have seen greater use of related techniques like small angle X-ray scattering CT and pair distribution function CT. Additionally, the adoption of machine learning techniques for tomographic reconstruction and data analysis are fundamentally disrupting how XDS-CT data is processed. The following narrative review highlights recent developments and applications of XDS-CT with a focus on studies in the last five years. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
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Affiliation(s)
- Naomi E. Omori
- Finden Limited, Merchant House, 5 East St Helens Street,Abingdon OX14 5EG, UK
| | - Antonia D. Bobitan
- Finden Limited, Merchant House, 5 East St Helens Street,Abingdon OX14 5EG, UK
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0FA, UK
| | - Antonis Vamvakeros
- Finden Limited, Merchant House, 5 East St Helens Street,Abingdon OX14 5EG, UK
- Dyson School of Design Engineering, Imperial College London, London SW7 2DB, UK
| | - Andrew M. Beale
- Finden Limited, Merchant House, 5 East St Helens Street,Abingdon OX14 5EG, UK
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon OX11 0FA, UK
| | - Simon D. M. Jacques
- Finden Limited, Merchant House, 5 East St Helens Street,Abingdon OX14 5EG, UK
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3
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Wortman J, Igenegbai VO, Almallahi R, Motagamwala AH, Linic S. Optimizing hierarchical membrane/catalyst systems for oxidative coupling of methane using additive manufacturing. NATURE MATERIALS 2023:10.1038/s41563-023-01687-x. [PMID: 37828102 DOI: 10.1038/s41563-023-01687-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 09/12/2023] [Indexed: 10/14/2023]
Abstract
The advantage of a membrane/catalyst system in the oxidative coupling of methane compared with conventional reactive systems is that by introducing oxygen into the catalytic sites through a membrane, the parasitic gas-phase reactions of O2(g)-responsible for lowering product selectivity-can be avoided. The design and fabrication of membrane/catalyst systems has, however, been hampered by low volumetric chemical conversion rates, high capital cost and difficulties in co-designing membrane and catalyst properties to optimize the performance. Here we solve these issues by developing a dual-layer additive manufacturing process, based on phase inversion, to design, fabricate and optimize a hollow-fibre membrane/catalyst system for the oxidative coupling of methane. We demonstrate the approach through a case study using BaCe0.8Gd0.2O3-δ as the basis of both catalyst and separation layers. We show that by using the manufacturing approach, we can co-design the membrane thickness and catalyst surface area so that the flux of oxygen transport through the membrane and methane activation rates in the catalyst layer match each other. We demonstrate that this 'rate matching' is critical for maximizing the performance, with the membrane/catalyst system substantially overperforming conventional reactor designs under identical conditions.
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Affiliation(s)
- James Wortman
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
- Catalysis Science and Technology Institute, University of Michigan, Ann Arbor, MI, USA
| | - Valentina Omoze Igenegbai
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
- Catalysis Science and Technology Institute, University of Michigan, Ann Arbor, MI, USA
| | - Rawan Almallahi
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
- Catalysis Science and Technology Institute, University of Michigan, Ann Arbor, MI, USA
| | - Ali Hussain Motagamwala
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA
- Catalysis Science and Technology Institute, University of Michigan, Ann Arbor, MI, USA
| | - Suljo Linic
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI, USA.
- Catalysis Science and Technology Institute, University of Michigan, Ann Arbor, MI, USA.
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4
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Jensen AB, Christensen TEK, Weninger C, Birkedal H. Very large-scale diffraction investigations enabled by a matrix-multiplication facilitated radial and azimuthal integration algorithm: MatFRAIA. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:1420-1428. [PMID: 36345750 PMCID: PMC9641557 DOI: 10.1107/s1600577522008232] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 08/17/2022] [Indexed: 05/22/2023]
Abstract
As synchrotron facilities continue to generate increasingly brilliant X-rays and detector speeds increase, swift data reduction from the collected area detector images to more workable 1D diffractograms becomes of increasing importance. This work reports an integration algorithm that can integrate diffractograms in real time on modern laptops and can reach 10 kHz integration speeds on modern workstations using an efficient pixel-splitting and parallelization scheme. This algorithm is limited not by the computation of the integration itself but is rather bottlenecked by the speed of the data transfer to the processor, the data decompression and/or the saving of results. The algorithm and its implementation is described while the performance is investigated on 2D scanning X-ray diffraction/fluorescence data collected at the interface between an implant and forming bone.
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Affiliation(s)
| | - Thorbjørn Erik Køppen Christensen
- Department of Chemistry and iNANO, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark
- Sino-Danish College (SDC), University of Chinese Academy of Sciences, People’s Republic of China
| | | | - Henrik Birkedal
- Department of Chemistry and iNANO, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus, Denmark
- Correspondence e-mail:
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5
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Thyssen VV, Vilela VB, de Florio DZ, Ferlauto AS, Fonseca FC. Direct Conversion of Methane to C 2 Hydrocarbons in Solid-State Membrane Reactors at High Temperatures. Chem Rev 2021; 122:3966-3995. [PMID: 34962796 DOI: 10.1021/acs.chemrev.1c00447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Direct conversion of methane to C2 compounds by oxidative and nonoxidative coupling reactions has been intensively studied in the past four decades; however, because these reactions have intrinsic severe thermodynamic constraints, they have not become viable industrially. Recently, with the increasing availability of inexpensive "green electrons" coming from renewable sources, electrochemical technologies are gaining momentum for reactions that have been challenging for more conventional catalysis. Using solid-state membranes to control the reacting species and separate products in a single step is a crucial advantage. Devices using ionic or mixed ionic-electronic conductors can be explored for methane coupling reactions with great potential to increase selectivity. Although these technologies are still in the early scaling stages, they offer a sustainable path for the utilization of methane and benefit from the advances in both solid oxide fuel cells and electrolyzers. This review identifies promising developments for solid-state methane conversion reactors by assessing multifunctional layers with microstructural control; combining solid electrolytes (proton and oxygen ion conductors) with active and selective electrodes/catalysts; applying more efficient reactor designs; understanding the reaction/degradation mechanisms; defining standards for performance evaluation; and carrying techno-economic analysis.
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Affiliation(s)
- Vivian Vazquez Thyssen
- Nuclear and Energy Research Institute (IPEN-CNEN), Av. Lineu Prestes, 2242, 05508-000 São Paulo, SP, Brazil
| | - Vanessa Bezerra Vilela
- Nuclear and Energy Research Institute (IPEN-CNEN), Av. Lineu Prestes, 2242, 05508-000 São Paulo, SP, Brazil
| | - Daniel Zanetti de Florio
- Center for Engineering, Modeling and Applied Social Sciences, Federal University of ABC (UFABC), Av. dos Estados, 5001, 09210-580 Santo André, SP, Brazil
| | - Andre Santarosa Ferlauto
- Center for Engineering, Modeling and Applied Social Sciences, Federal University of ABC (UFABC), Av. dos Estados, 5001, 09210-580 Santo André, SP, Brazil
| | - Fabio Coral Fonseca
- Nuclear and Energy Research Institute (IPEN-CNEN), Av. Lineu Prestes, 2242, 05508-000 São Paulo, SP, Brazil
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6
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Vamvakeros A, Matras D, Ashton TE, Coelho AA, Dong H, Bauer D, Odarchenko Y, Price SWT, Butler KT, Gutowski O, Dippel AC, Zimmerman MV, Darr JA, Jacques SDM, Beale AM. Cycling Rate-Induced Spatially-Resolved Heterogeneities in Commercial Cylindrical Li-Ion Batteries. SMALL METHODS 2021; 5:e2100512. [PMID: 34928070 DOI: 10.1002/smtd.202100512] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/29/2021] [Indexed: 06/14/2023]
Abstract
Synchrotron high-energy X-ray diffraction computed tomography has been employed to investigate, for the first time, commercial cylindrical Li-ion batteries electrochemically cycled over the two cycling rates of C/2 and C/20. This technique yields maps of the crystalline components and chemical species as a cross-section of the cell with high spatiotemporal resolution (550 × 550 images with 20 × 20 × 3 µm3 voxel size in ca. 1 h). The recently developed Direct Least-Squares Reconstruction algorithm is used to overcome the well-known parallax problem and led to accurate lattice parameter maps for the device cathode. Chemical heterogeneities are revealed at both electrodes and are attributed to uneven Li and current distributions in the cells. It is shown that this technique has the potential to become an invaluable diagnostic tool for real-world commercial batteries and for their characterization under operating conditions, leading to unique insights into "real" battery degradation mechanisms as they occur.
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Affiliation(s)
- Antonis Vamvakeros
- Finden Limited, Merchant House, 5 East St Helens Street, Abingdon, OX14 5EG, UK
| | - Dorota Matras
- The Faraday Institution, Quad One, Harwell Science and Innovation Campus, Didcot, OX11 0RA, UK
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Thomas E Ashton
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Alan A Coelho
- Coelho Software, 72 Cedar Street, Wynnum, Brisbane, Queensland, 4178, Australia
| | - Hongyang Dong
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Dustin Bauer
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Yaroslav Odarchenko
- Finden Limited, Merchant House, 5 East St Helens Street, Abingdon, OX14 5EG, UK
| | - Stephen W T Price
- Finden Limited, Merchant House, 5 East St Helens Street, Abingdon, OX14 5EG, UK
| | - Keith T Butler
- SciML, Scientific Computer Division, Rutherford Appleton Laboratory, Harwell, OX11 0QX, UK
| | - Olof Gutowski
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany
| | - Ann-Christin Dippel
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany
| | | | - Jawwad A Darr
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Simon D M Jacques
- Finden Limited, Merchant House, 5 East St Helens Street, Abingdon, OX14 5EG, UK
| | - Andrew M Beale
- Finden Limited, Merchant House, 5 East St Helens Street, Abingdon, OX14 5EG, UK
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
- Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxon, OX11 0FA, UK
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7
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Mürer FK, Madathiparambil AS, Tekseth KR, Di Michiel M, Cerasi P, Chattopadhyay B, Breiby DW. Orientational mapping of minerals in Pierre shale using X-ray diffraction tensor tomography. IUCRJ 2021; 8:747-756. [PMID: 34584736 PMCID: PMC8420771 DOI: 10.1107/s205225252100587x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 06/07/2021] [Indexed: 06/13/2023]
Abstract
Shales have a complex mineralogy with structural features spanning several length scales, making them notoriously difficult to fully understand. Conventional attenuation-based X-ray computed tomography (CT) measures density differences, which, owing to the heterogeneity and sub-resolution features in shales, makes reliable interpretation of shale images a challenging task. CT based on X-ray diffraction (XRD-CT), rather than intensity attenuation, is becoming a well established technique for non-destructive 3D imaging, and is especially suited for heterogeneous and hierarchical materials. XRD patterns contain information about the mineral crystal structure, and crucially also crystallite orientation. Here, we report on the use of orientational imaging using XRD-CT to study crystallite-orientation distributions in a sample of Pierre shale. Diffraction-contrast CT data for a shale sample measured with its bedding-plane normal aligned parallel to a single tomographic axis perpendicular to the incoming X-ray beam are discussed, and the spatial density and orientation distribution of clay minerals in the sample are described. Finally, the scattering properties of highly attenuating inclusions in the shale bulk are studied, which are identified to contain pyrite and clinochlore. A path forward is then outlined for systematically improving the structural description of shales.
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Affiliation(s)
- Fredrik K. Mürer
- PoreLab, Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, Trondheim 7491, Norway
| | - Aldritt Scaria Madathiparambil
- PoreLab, Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, Trondheim 7491, Norway
| | - Kim Robert Tekseth
- PoreLab, Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, Trondheim 7491, Norway
| | - Marco Di Michiel
- ESRF, The European Synchrotron, 71 Avenue des Martyrs, Grenoble 38000, France
| | - Pierre Cerasi
- Petroleum Department, SINTEF Industry, Trondheim 7465, Norway
| | - Basab Chattopadhyay
- PoreLab, Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, Trondheim 7491, Norway
| | - Dag W. Breiby
- PoreLab, Department of Physics, Norwegian University of Science and Technology, Høgskoleringen 5, Trondheim 7491, Norway
- Department of Microsystems, University of South-Eastern Norway, Campus Vestfold, Borre 3184, Norway
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8
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Sample Environment for Operando Hard X-ray Tomography—An Enabling Technology for Multimodal Characterization in Heterogeneous Catalysis. Catalysts 2021. [DOI: 10.3390/catal11040459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Structure–activity relations in heterogeneous catalysis can be revealed through in situ and operando measurements of catalysts in their active state. While hard X-ray tomography is an ideal method for non-invasive, multimodal 3D structural characterization on the micron to nm scale, performing tomography under controlled gas and temperature conditions is challenging. Here, we present a flexible sample environment for operando hard X-ray tomography at synchrotron radiation sources. The setup features are discussed, with demonstrations of operando powder X-ray diffraction tomography (XRD-CT) and energy-dispersive tomographic X-ray absorption spectroscopy (ED-XAS-CT). Catalysts for CO2 methanation and partial oxidation of methane are shown as case studies. The setup can be adapted for different hard X-ray microscopy, spectroscopy, or scattering synchrotron radiation beamlines, is compatible with absorption, diffraction, fluorescence, and phase-contrast imaging, and can operate with scanning focused beam or full-field acquisition mode. We present an accessible methodology for operando hard X-ray tomography studies, which offer a unique source of 3D spatially resolved characterization data unavailable to contemporary methods.
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9
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Multi-Scale Studies of 3D Printed Mn–Na–W/SiO2 Catalyst for Oxidative Coupling of Methane. Catalysts 2021. [DOI: 10.3390/catal11030290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
This work presents multi-scale approaches to investigate 3D printed structured Mn–Na–W/SiO2 catalysts used for the oxidative coupling of methane (OCM) reaction. The performance of the 3D printed catalysts has been compared to their conventional analogues, packed beds of pellets and powder. The physicochemical properties of the 3D printed catalysts were investigated using scanning electron microscopy, nitrogen adsorption and X-ray diffraction (XRD). Performance and durability tests of the 3D printed catalysts were conducted in the laboratory and in a miniplant under real reaction conditions. In addition, synchrotron-based X-ray diffraction computed tomography technique (XRD-CT) was employed to obtain cross sectional maps at three different positions selected within the 3D printed catalyst body during the OCM reaction. The maps revealed the evolution of catalyst active phases and silica support on spatial and temporal scales within the interiors of the 3D printed catalyst under operating conditions. These results were accompanied with SEM-EDS analysis that indicated a homogeneous distribution of the active catalyst particles across the silica support.
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10
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Vamvakeros A, Coelho AA, Matras D, Dong H, Odarchenko Y, Price SWT, Butler KT, Gutowski O, Dippel AC, Zimmermann M, Martens I, Drnec J, Beale AM, Jacques SDM. DLSR: a solution to the parallax artefact in X-ray diffraction computed tomography data. J Appl Crystallogr 2020. [DOI: 10.1107/s1600576720013576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A new tomographic reconstruction algorithm is presented, termed direct least-squares reconstruction (DLSR), which solves the well known parallax problem in X-ray-scattering-based experiments. The parallax artefact arises from relatively large samples where X-rays, scattered from a scattering angle 2θ, arrive at multiple detector elements. This phenomenon leads to loss of physico-chemical information associated with diffraction peak shape and position (i.e. altering the calculated crystallite size and lattice parameter values, respectively) and is currently the major barrier to investigating samples and devices at the centimetre level (scale-up problem). The accuracy of the DLSR algorithm has been tested against simulated and experimental X-ray diffraction computed tomography data using the TOPAS software.
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11
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Matras D, Vamvakeros A, Jacques SDM, Middelkoop V, Vaughan G, Agote Aran M, Cernik RJ, Beale AM. In situ X-ray diffraction computed tomography studies examining the thermal and chemical stabilities of working Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3-δ membranes during oxidative coupling of methane. Phys Chem Chem Phys 2020; 22:18964-18975. [PMID: 32597462 DOI: 10.1039/d0cp02144j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study we present the results from two in situ X-ray diffraction computed tomography experiments of catalytic membrane reactors (CMRs) using Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) hollow fibre membranes and Na-Mn-W/SiO2 catalyst during the oxidative coupling of methane (OCM) reaction. The negative impact of CO2, when added to the inlet gas stream, is seen to be mainly related to the C2+ yield, while no evidence of carbonate phase(s) formation is found during the OCM experiments. The main degradation mechanism of the CMR is suggested to be primarily associated with the solid-state evolution of the BSCF phase rather than the presence of CO2. Specifically, in situ XRD-CT and post-mortem SEM/EDX measurements revealed a collapse of the cubic BSCF phase and subsequent formation of secondary phases, which include needle-like structures and hexagonal Ba6Co4O12 and formation of a BaWO4 layer, the latter being a result of chemical interaction between the membrane and catalyst materials at high temperatures.
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Affiliation(s)
- Dorota Matras
- School of Materials, University of Manchester, Manchester, Lancashire M13 9PL, UK. and Research Complex at Harwell, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK
| | - Antonis Vamvakeros
- Research Complex at Harwell, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and Finden Limited, Merchant House, 5 East St Helen Street, Abingdon, OX14 5EG, UK. and Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
| | - Simon D M Jacques
- Finden Limited, Merchant House, 5 East St Helen Street, Abingdon, OX14 5EG, UK.
| | - Vesna Middelkoop
- Sustainable Materials Management, Flemish Institute for Technological Research, VITO NV, Boeretang 200, Mol, Belgium
| | - Gavin Vaughan
- ESRF - The European Synchrotron, Grenoble, 38000, France
| | - Miren Agote Aran
- Research Complex at Harwell, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
| | - Robert J Cernik
- School of Materials, University of Manchester, Manchester, Lancashire M13 9PL, UK.
| | - Andrew M Beale
- Research Complex at Harwell, Harwell Science and Innovation Campus, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0FA, UK and Finden Limited, Merchant House, 5 East St Helen Street, Abingdon, OX14 5EG, UK. and Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
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