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9. Multimodal Insights of Regeneration Dynamics of Spent Bimetallic Catalysts by Full Field Hyperspectral Quick‐EXAFS Imaging and Environmental Transmission Electron Microscopy.

Author

Briois, Valérie, Nelayah, Jaysen, La Fontaine, Camille, Roudenko, Olga, Beauvois, Anthony, Passos, Aline Ribeiro, and Alloyeau, Damien

Subjects
*SCANNING transmission electron microscopy, *BIMETALLIC catalysts, *KIRKENDALL effect, *TRANSMISSION electron microscopy, *COPPER, *ETHANOL, *STEAM reforming
Abstract

Multimodal measurements involving time‐resolved Ni and Cu K edges Quick‐EXAFS, time‐resolved hyperspectral Full Field Quick‐EXAFS imaging with micrometer spatial resolution and aberration‐corrected Environmental Scanning Transmission Electron Microscopy have been performed over a NiCu catalyst used for the ethanol steam reforming reaction to establish structure‐activity relationships after regeneration. Activated catalysts are composed of 5–10 nm monometallic nickel nanoparticles and larger bimetallic randomly alloyed NiCu nanoparticles (NPs). After 3 h time on reactive stream, the monitoring of the regeneration of the coked deactivated catalyst at 500 °C by Full Field hyperspectral XAS imaging evidences that the oxidative propagation front affects faster metallic Ni species than metallic Cu ones as a result of the stronger oxophilic character of the former compared to the latter. Furthermore, ESTEM characterization of the deactivated catalyst when passing from H2 to O2 atmosphere at 500 °C for burning coke deposits evidences the fragmentation of the Ni and NiCu‐NPs driven by the Kirkendall effect in the encapsulated coked catalyst. The resulting increase of specific surface of active species is assumed to be responsible for the activity boost observed after regeneration. [ABSTRACT FROM AUTHOR]

Published
2024
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10. Hyperspectral full‐field quick‐EXAFS imaging at the ROCK beamline for monitoring micrometre‐sized heterogeneity of functional materials under process conditions.

Author

Briois, Valérie, Itié, Jean Paul, Polian, Alain, King, Andrew, Traore, Aliou Sadia, Marceau, Eric, Ersen, Ovidiu, La Fontaine, Camille, Barthe, Laurent, Beauvois, Anthony, Roudenko, Olga, and Belin, Stéphanie

Subjects
*SPIN crossover, *FOCUS (Optics), *MANUFACTURING processes, *SINGLE crystals, *COPPER
Abstract

Full‐field transmission X‐ray microscopy has been recently implemented at the hard X‐ray ROCK–SOLEIL quick‐EXAFS beamline, adding micrometre spatial resolution to the second time resolution characterizing the beamline. Benefiting from a beam size versatility due to the beamline focusing optics, full‐field hyperspectral XANES imaging has been successfully used at the Fe K‐edge for monitoring the pressure‐induced spin transition of a 150 µm × 150 µm Fe(o‐phen)2(NCS)2 single crystal and the charge of millimetre‐sized LiFePO4 battery electrodes. Hyperspectral imaging over 2000 eV has been reported for the simultaneous monitoring of Fe and Cu speciation changes during activation of a FeCu bimetallic catalyst along a millimetre‐sized catalyst bed. Strategies of data acquisition and post‐data analysis using Jupyter notebooks and multivariate data analysis are presented, and the gain obtained using full‐field hyperspectral quick‐EXAFS imaging for studies of functional materials under process conditions in comparison with macroscopic information obtained by non‐spatially resolved quick‐EXAFS techniques is discussed. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Elucidating Salt Conversion Mechanisms of Lithiated Transition Metal Oxides for Lithium-Ion Battery Recycling

Author

Hamitouche, Lydia, primary, Robert, Clara, additional, Rollet, Anne-Laure, additional, Briois, Valérie, additional, Selmane, Mohamed, additional, Porras Gutierrez, Ana Gabriela, additional, Leclerc, Sandrine, additional, Krulic, Denise, additional, Fatouros, Nicolas, additional, Sirieix-Plénet, Juliette, additional, Michot, Laurent, additional, Doublet, Marie-Liesse, additional, and Dambournet, Damien, additional

Published
2024
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20. Hydrodeoxygenation of Furfural over Unsupported, SiO2‐supported or Metal‐promoted Mo Carbides: Tunning the Selectivity between 2‐Methylfuran and C10 Furoins Diesel Precursors

Author

Sosa, Letícia F., primary, de Souza, Priscilla M., additional, Rafael, Raphaela A., additional, Wojcieszak, Robert, additional, Marceau, Eric, additional, Paul, Sébastien, additional, Briois, Valérie, additional, Noronha, Fabio B., additional, and Toniolo, Fabio S., additional

Published
2023
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21. Hydrodeoxygenation of Furfural over Unsupported, SiO2‐supported or Metal‐promoted Mo Carbides: Tunning the Selectivity between 2‐Methylfuran and C10 Furoins Diesel Precursors.

Author

Sosa, Letícia F., de Souza, Priscilla M., Rafael, Raphaela A., Wojcieszak, Robert, Marceau, Eric, Paul, Sébastien, Briois, Valérie, Noronha, Fabio B., and Toniolo, Fabio S.

Subjects
FURFURAL, CARBIDES, OXIDATION states, COPPER
Abstract

The hydrodeoxygenation of furfural (FF) over Mo carbides in liquid phase at 200 °C, 30 bar of H2 for 4 h in 2‐butanol was investigated. Unsupported and SiO2‐supported Mo carbide with different crystallographic phases (β‐Mo2C/SiO2 and α‐MoC/SiO2), and in the presence of Cu and Ni as promoters were studied. The reactivation treatment under H2 atmosphere of the passivated Mo carbides was investigated by XAS. The results show that Mo is present in different states of oxidation in the passivated catalysts, with more severe oxidation in the bimetallic systems, in which the original carbides are not restored after reactivation. Finally, the product distribution in the HDO of furfural is modified as a function of catalyst oxidation degree. Using the less oxidized Mo carbide (β‐Mo2C), a higher yield to 2‐methylfuran is obtained, while C10 condensation products are formed for the more oxidized catalysts. [ABSTRACT FROM AUTHOR]

Published
2024
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22. Development of a custom-made 2.8 T permanent-magnet dipole photon source for the ROCK beamline at SOLEIL

Author

Brunelle, Pascale, primary, Béchu, Nicolas, additional, Briois, Valérie, additional, Marteau, Fabrice, additional, Ribbens, Marc, additional, Berteaud, Philippe, additional, Delétoille, Xavier, additional, Dupuy, Eric, additional, Herbeaux, Christian, additional, Labat, Marie, additional, Lestrade, Alain, additional, Nadji, Amor, additional, Nadolski, Laurent, additional, Nouna, Mohamed, additional, and Pruvost, Jean-Baptiste, additional

Published
2023
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26. Mechanism of formation of Co–Ru nanoalloys: the key role of Ru in the reduction pathway of Co.

Author

Azeredo, Brandon, Ben Ghzaiel, Tayssir, Huang, Ning, Nowak, Sophie, Peron, Jennifer, Giraud, Marion, Balachandran, Jeyadevan, Taché, Olivier, Barthe, Laurent, Piquemal, Jean-Yves, Briois, Valérie, and Sicard, Lorette

Abstract

The chemical synthesis of alloy nanoparticles requires adequate conditions to enable co-reduction instead of separate reduction of the two metal cations. The mechanism of formation of bimetallic cobalt–ruthenium nanoalloys by reducing metal salts in an alcohol medium was explored to draw general rules to extrapolate to other systems. The relative kinetics of the reduction of both metal cations were studied by UV-visible and in situ Quick-X-ray absorption spectroscopies as well as H2 evolution. The addition of Co(II) ions does not influence the reduction kinetics of Ru(III) but adding Ru(III) to a Co(II) solution promotes the reduction of cobalt cations. Indeed, while CoO is formed when reaching the boiling temperature of the solvent for the monometallic system, a direct reduction of Co is observed at this temperature without formation of the oxide for the bimetallic one. The co-reduction of the metal cations results in the formation of bimetallic nanoplatelets, the size of which can be tuned by changing the Ru content. [ABSTRACT FROM AUTHOR]

Published
2023
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32. Development of a custom-made 2.8 T permanentmagnet dipole photon source for the ROCK beamline at SOLEIL.

Author

Brunelle, Pascale, Béchu, Nicolas, Briois, Valérie, Marteau, Fabrice, Ribbens, Marc, Berteaud, Philippe, Dele'toille, Xavier, Dupuy, Eric, Herbeaux, Christian, Labat, Marie, Lestrade, Alain, Nadji, Amor, Nadolski, Laurent, Nouna, Mohamed, and Pruvost, Jean-Baptiste

Subjects
BEAM dynamics, PHOTON flux, MAGNETISM, PERMANENT magnets, MAGNETIC fields, ELECTRON beams
Abstract

In August 2021, the SOLEIL storage ring was restarted after the summer shutdown with a new bending magnet made entirely of permanent magnets. Producing a magnetic field of 2.8 T, it replaced one of the 32 electromagnetic dipoles (magnetic field of 1.7 T) of the ring to allow the ROCK beamline to exploit more intense photon fluxes in the hard X-ray range, thus improving the time resolution performances of the beamline for experiments carried out above 20 keV. The reduction of the new dipole magnetic gap required to produce the higher field has led to the construction and installation of a new vacuum vessel. The realization of the new dipole with permanent magnets was a technological feat due to the very strong magnetic forces. The permanent-magnet assembly required dedicated tools to be designed and constructed. Thanks to accurate magnetic measurements, a precise modelization of the new dipole was performed to identify its effects on the electron beam dynamics. The first measurements carried out on the ROCK beamline have highlighted the expected increase in photon flux, and the operation performances remain unchanged for the other beamlines. Here, the major developments and results of this innovative project are described in terms of technology, electron beam dynamics and photon beam performance on the ROCK beamline. [ABSTRACT FROM AUTHOR]

Published
2023
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35. Chemical Speciation by Quick‐XAS and Raman Spectroscopy: Validation of Two Cells for in situ Time‐Resolved Monitoring of the Impregnation and Drying of CoMoP/Al2O3 Catalysts.

Author

Barata, Beatriz, Legens, Christèle, Devers, Elodie, Delpoux, Olivier, Barthe, Laurent, Roudenko, Olga, and Briois, Valérie

Subjects
CHEMICAL speciation, RAMAN spectroscopy, CATALYSTS, HETEROGENEOUS catalysis, TIME-resolved spectroscopy, X-ray absorption, DESULFURIZATION
Abstract

This paper aims to describe and validate two cells designed to monitor, by in situ quick‐EXAFS, the transformation of Mo based oxidic species occurring during maturation and drying preparation steps of a single hydrodesulfurization catalyst. These transformations occur firstly upon impregnation/maturation, due to the contact of the acidic impregnation solution with the basic alumina support, and furthermore upon drying. The Mo K edge in situ quick‐EXAFS monitoring of these two elementary preparation steps is hereby reported for the first time, providing quantitative results of the Mo‐speciation. Ex situ Raman spectroscopy is used effectively as a complement. It considers an impregnation solution with a Mo concentration of 0.75 M and molar ratios of P/Mo 0.56 and Co/Mo 0.4. A two‐step drying mechanism is proposed to explain the evolution of the Mo‐speciation during in situ drying where Strandberg's, Anderson's and Dawson's HPAs are transformed into lacunary Keggin's HPA, octa‐ and monomolybdates. [ABSTRACT FROM AUTHOR]

Published
2023
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43. Using Transient XAS to Detect Minute Levels of Reversible S-O Exchange at the Active Sites of MoS2-Based Hydrotreating Catalysts: Effect of Metal Loading, Promotion, Temperature, and Oxygenate Reactant

Author

Gaur, Abhijeet, primary, Stehle, Matthias, additional, Serrer, Marc-André, additional, Stummann, Magnus Zingler, additional, La Fontaine, Camille, additional, Briois, Valérie, additional, Grunwaldt, Jan-Dierk, additional, and Høj, Martin, additional

Published
2021
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46. Carbon-based catalysts for Fischer–Tropsch synthesis

Author

Ordomsky, Vitaly, Wang, Qiyan, Zhou, Wen-Juan, Heyte, Svetlana, Thuriot-Roukos, Joëlle, Marinova, Maya, Addad, Ahmed, Rouzière, Stéphan, Simon, Pardis, Capron, Mickael, Zhang, Linjie, Grimaud, Alexis, Schwiedernoch, Renate, Hernández, Willinton Yesid, Naghavi, Negar, Pedrolo, Débora, Schwaab, Marcio, Marcilio, Nilson, Khodakov, Andrei, Santos, Sara, Urbina-Blanco, César, Zhou, Wenjuan, Yang, Yong, Joelle, Thuriot-Roukos, Ersen, Ovidiu, Baaziz, Walid, Safonova, Olga, Saeys, Mark, Gu, Bang, Peron, Deizi, Barrios, Alan, Virginie, Mirella, La Fontaine, Camille, Briois, Valérie, Vorokhta, Mykhailo, Šmíd, Břetislav, Moldovan, Simona, Koneti, Siddardha, Gambu, Thobani, Hernández, Willinton, Impéror-Clerc, Marianne, Vovk, Evgeny, Wu, Dan, Nuns, Nicolas, Palčić, Ana, Jaén, Sara Navarro, Cai, Mengdie, Liu, Chong, Pidko, Evgeny, Valtchev, Valentin, Yan, Zhen, Zhang, Songwei, Li, Jerry Pui Ho, Zhao, Jingpeng, Yuan, Biao, He, Tao, Yu, Yi, Li, Tao, Hu, Di, Chen, Yanping, Wei, Jiatong, Duyar, Melis, Liu, Jian, Dalian Institute of Chemical Physics - Chinese Academy of Sciences, University of Surrey (UNIS), Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE06-0013,NANO4FuT,Synthèse des carburants alternatifs et des molécules plateforme sur nanoréacteurs(2016), CNRS, Centrale Lille, ENSCL, Univ. Artois, Université de Lille, Unité de Catalyse et Chimie du Solide (UCCS) - UMR 8181, Ordomsky, Vitaly, Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Eco-Efficient Products &Processes Laboratory (E2PL2), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-RHODIA, Laboratoire de Chimie - UMR5182 (LC), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon)-Institut de Chimie du CNRS (INC), Institut Michel Eugène Chevreul - FR 2638 (IMEC), Université d'Artois (UA)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centrale Lille Institut (CLIL), Unité Matériaux et Transformations - UMR 8207 (UMET), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Laboratoire de Physique des Solides (LPS), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Chimie du solide et de l'énergie (CSE), Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Solvay (France), Instituto Federal do Rio Grande do Sul (IFRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut de chimie et procédés pour l'énergie, l'environnement et la santé (ICPEES), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Paul Scherrer Institute (PSI), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Charles University [Prague] (CU), Groupe de physique des matériaux (GPM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Ruđer Bošković Institute (IRB), Delft University of Technology (TU Delft), Laboratoire catalyse et spectrochimie (LCS), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Université de Caen Normandie (UNICAEN), ShanghaiTech University [Shanghai], Beihang University (BUAA), School of Physics Science and Engineering, Tongji University, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille, Eco-Efficient Products & Processes Laboratory (E2P2L), RHODIA-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)

Subjects
Materials science, chemistry.chemical_element, 02 engineering and technology, Carbon nanotube, 010402 general chemistry, 01 natural sciences, 7. Clean energy, law.invention, Catalysis, law, [CHIM] Chemical Sciences, medicine, [CHIM]Chemical Sciences, Coal, Gasoline, Carbon nanofiber, business.industry, Fischer–Tropsch process, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical engineering, chemistry, 0210 nano-technology, business, Carbon, Activated carbon, medicine.drug
Abstract

International audience; Fischer-Tropsch synthesis (FTS) is an essential approach to convert coal, biomass, and shale gas into fuels and chemicals, such as lower olefins, gasoline, diesel, and so on. In recent years, there has been increasing motivation to deploy FTS at commercial scales which has been boosting the discovery of high performance catalysts. In particular, the importance of support in modulating the activity of metals has been recognized and carbonaceous materials have attracted attention as supports for FTS. In this review, we summarised the substantial progress in the preparation of carbon-based catalysts for FTS by applying activated carbon (AC), carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon spheres (CSs), and metal-organic frameworks (MOFs) derived carbonaceous materials as supports. A general assessment of carbon-based catalysts for FTS, concerning the support and metal properties, activity and products selectivity, and their interactions is systematically discussed. Finally, current challenges and future trends in the development of carbon-based catalysts for commercial utilization in FTS are proposed.

Published
2021

49. Fe-based bimetallic catalysts: evidencing the interplay between the two metals using in situ/operando XAS and chemometrics

Author

Marceau, E., Shi, Dichao, Girardon, Jean-Sébastien, Constant, Anne, Sébastien, Paul, Khodakov, Andrei, Gu, Bang, V., Ordomsky, Briois, Valérie, Banerjee, Dipanjan, Unité de Catalyse et Chimie du Solide - UMR 8181 (UCCS), Université d'Artois (UA)-Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), and Centrale Lille Institut (CLIL)-Université d'Artois (UA)-Centrale Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Lille

Subjects
[CHIM.CATA]Chemical Sciences/Catalysis, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2020

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