Search

Your search keyword '"Moulay Tahar, Sougrati"' showing total 262 results
Start Over Author "Moulay Tahar, Sougrati"
262 results on '"Moulay Tahar, Sougrati"'

1. KFe(C2O4)F: A Fluoro‐oxalate Cathode Material for Li/Na‐Ion Batteries

Author

Dr. Atin Pramanik, Alexis G. Manche, Megan T. Smeaton, Dr. Moulay‐Tahar Sougrati, Prof. Philip Lightfoot, and Dr. Anthony Robert Armstrong

Subjects
cathode materials, electrochemistry, Na-ion/Li-ion, oxalate, rechargeable battery, Industrial electrochemistry, TP250-261, Chemistry, QD1-999
Abstract

Abstract The iron‐based polyanionic fluoro‐oxalate material, KFe(C2O4)F (KFCF), has been synthesized by hydrothermal methods. This compound shows promising reversible lithium and sodium insertion properties as a cathode material. The material delivered a first‐cycle discharge capacity of 120 mAh g−1 at ∼3.3 V (Li+/Li) and 97.4 mAh g−1 at ∼3.0 V (Na+/Na) in LIB and NIB, respectively. Stable cycling performance was observed in both cases. The involvement of reversible Fe2+/Fe3+ redox was confirmed by ex‐situ Mössbauer spectroscopy supported by first‐principles calculations. This study reveals promising performance from a mixed oxalate‐fluoride based polyanionic material thereby opening up further possibilities for materials discovery in the design of new electrode materials.

Published
2023
Full Text
View/download PDF

2. Understanding how single-atom site density drives the performance and durability of PGM-free Fe–N–C cathodes in anion exchange membrane fuel cells

Author

Horie Adabi, Pietro Giovanni Santori, Abolfazl Shakouri, Xiong Peng, Karam Yassin, Igal G. Rasin, Simon Brandon, Dario R. Dekel, Noor Ul Hassan, Moulay-Tahar Sougrati, Andrea Zitolo, John R. Varcoe, John R. Regalbuto, Frédéric Jaouen, and William E. Mustain

Subjects
PGM-free, AEM, Fuel cell, Oxygen reduction, High performance, Fe–N–C, Materials of engineering and construction. Mechanics of materials, TA401-492
Abstract

One of the most important needs for the future of low-cost fuel cells is the development of highly active platinum group metal (PGM)-free catalysts. For the oxygen reduction reaction, Fe–N–C materials have been widely studied in both acid and alkaline media. However, reported catalysts in the literature show quite different intrinsic activity and in-cell performance, despite similar synthesis routes and precursors. Here, two types of Fe–N–C are prepared from the same precursor and procedure – the main difference is how the precursor was handled prior to use. It is shown that in one case Fe overwhelmingly existed as highly active single-metal atoms in FeN4 coordination (preferred), while in the other case large Fe particles coexisting with few single metal atoms were obtained. As a result, there were drastic differences in the catalyst structure, activity, and especially in their performance in an operating anion exchange membrane fuel cell (AEMFC). Additionally, it is shown that catalyst layers created from single-atom-dominated Fe–N–C can have excellent performance and durability in an AEMFC using H2/O2 reacting gases, achieving a peak power density of 1.8 W cm−2 – comparable to similar AEMFCs with a Pt/C cathode – and being able to operate stably for more than 100 h. Finally, the Fe–N–C cathode was paired with a low-loading PtRu/C anode electrode to create AEMFCs (on H2/O2) with a total PGM loading of only 0.135 mg cm−2 (0.090 mgPt cm−2) that was able to achieve a very high specific power of 8.4 W mgPGM−1 (12.6 W mgPt−1).

Published
2021
Full Text
View/download PDF

3. Insertion of fluorine into a LiFePO4 electrode material by gas-solid fluorination.

Author

Kevin, Lemoine, Roméo, Kenmogne-Debah, Léa, Doubtsof, Lawrence, Frezet, Elodie, Petit, Katia, Guerin, Bertrand, Devouard, Moulay-Tahar, Sougrati, Diane, Delbègue, and Pierre, Bonnet

Subjects
FLUORINATION, FLUORINE, NUCLEAR magnetic resonance, CORE materials, MOSSBAUER spectroscopy
Abstract

In this study, the insertion of fluorine into LiFePO4 was carried out under molecular fluorine F2 at different temperatures. The reactivity strongly depends on the applied fluorination temperature, leading to very different products: core delithiation of the material is observed at low temperatures with the formation of a LiF shell around particles, while the material decomposes to gradually form a mixture of α-FeF3 and α-Li3FeF6 iron fluorides at higher temperatures. A second thermal treatment under N2 leads to the formation of LiFePO4F in a new way that has not been reported before. Supported by X-ray diffraction, Raman, infrared, Mössbauer spectroscopies, 7Li nuclear magnetic resonance and electrochemical characterization of the different materials, this report demonstrates various fluorination mechanisms for LiFePO4, from chemical delithiation to the stable pure fluorinated form LiFePO4F and illustrates an innovative method that can be extended to obtain the triphylite form of NaFePO4. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

4. An oxalate cathode for lithium ion batteries with combined cationic and polyanionic redox

Author

Wenjiao Yao, A. Robert Armstrong, Xiaolong Zhou, Moulay-Tahar Sougrati, Pinit Kidkhunthod, Sarayut Tunmee, Chenghua Sun, Suchinda Sattayaporn, Philip Lightfoot, Bifa Ji, Chunlei Jiang, Nanzhong Wu, Yongbing Tang, and Hui-Ming Cheng

Subjects
Science
Abstract

Polyoxyanion compounds are alternative cathodes to conventional oxides, but their reliance on the transition metal redox limits the performance. Here the authors report an oxalate system which possesses additional polyanionic redox reactivity, suggesting a new direction for cathode materials design.

Published
2019
Full Text
View/download PDF

6. 5-Hydroxymethylfurfural Oxidation to 2,5-Furandicarboxylic Acid on Noble Metal-Free Nanocrystalline Mixed Oxide Catalysts

Author

Atif Emre Demet, Olinda Gimello, Rossella Arletti, Nathalie Tanchoux, Moulay Tahar Sougrati, Lorenzo Stievano, Françoise Quignard, Gabriele Centi, Siglinda Perathoner, and Francesco Di Renzo

Subjects
noble metal-free catalysts, HMF, FDCA, renewable resource, cobalt-iron oxides, copper-manganese oxides, Chemical technology, TP1-1185, Chemistry, QD1-999
Abstract

Noble metal-free catalysts based on earth-abundant and inexpensive mixed oxides are active catalysts of all steps of the reaction cascade leading from 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) using tert-butyl hydroperoxide (TBHP) as oxidation agent. Catalysts covering the whole range of composition in the Cu-Mn and Co-Fe series have been prepared and characterised. The nature and composition of the catalyst strongly affect conversion and selectivity. The distribution of products indicates that radical-type oxygen species, deriving from the activation of TBHP, play a determining role in the reaction. The early steps of reaction mainly follow the pattern expected for heterogeneous Fenton catalysts. Mixed oxide catalysts are the most effective in further oxidation steps, leading to the formation of FDCA, both in the Cu-Mn and Co-Fe systems. This behaviour can be related to the distribution of charge in the mixed oxides, suggesting a possible implication of the lattice oxygen in the last reaction steps. The results provide indications on how to optimize the reaction and minimize the formation of byproducts (humins and oligomers).

Published
2022
Full Text
View/download PDF

7. The structural and magnetic features of perovskite oxides La1–xSrxMnO3+δ (x = 0.05, 0.10, 0.20) depending on the strontium doping content and heat treatment

Author

Diana I. Pchelina, Vera D. Sedykh, Nataliya I. Chistyakova, Vyacheslav S. Rusakov, Yulia A. Alekhina, Alexey N. Tselebrovskiy, Bernard Fraisse, Lorenzo Stievano, and Moulay Tahar Sougrati

Subjects
Process Chemistry and Technology, Materials Chemistry, Ceramics and Composites, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials
Published
2023

9. Prussian blue analogues for potassium-ion batteries: insights into the electrochemical mechanisms

Author

Phuong Nam Le Pham, Romain Wernert, Maëlle Cahu, Moulay Tahar Sougrati, Giuliana Aquilanti, Patrik Johansson, Laure Monconduit, Lorenzo Stievano, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Advanced Lithium Energy Storage Systems - ALISTORE-ERI (ALISTORE-ERI), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Chalmers University of Technology [Göteborg], Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB), Université de Bordeaux (UB)-Institut Polytechnique de Bordeaux-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Aix Marseille Université (AMU)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Nantes Université (Nantes Univ)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Elettra Sincrotrone Trieste, Alistore-ERI (financement de la bourse de thèse de PNLPCERIC-ERIC for providing access at synchrotron Elettra (Trieste, Italie), ANR-19-CE05-0026,TROPIC,Vers des batteries innovantes K-ion(2019), ANR-10-LABX-0076,STORE-EX,Laboratory of excellency for electrochemical energy storage(2010), and ANR-18-CE09-0012,NANOBLUE,Nanoparticules de bleu de Prusse pour le théranostic(2018)

Subjects
Renewable Energy, Sustainability and the Environment, [CHIM]Chemical Sciences, General Materials Science, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry
Abstract

International audience; A comprehensive description of the electrochemical mechanisms of the Prussian blue analogue (PBA) K1.67Mn0.65Fe0.35[Fe(CN)6]0.92•0.45H2O is obtained by combining several complementary ex situ and operando physicochemical characterisation techniques. This particular PBA, which shows very good electrochemical performance as a cathode material in potassium-ion batteries (PIBs), undergoes three successive redox reactions during the (de-)potassiation that are hereby identified by ex situ 57 Fe Mössbauer spectroscopy and operando Mn and Fe K-edge X-ray absorption spectroscopy. These reactions come along with notable modifications of the crystal structure, which are followed in real time by operando X-ray diffraction. The correlation of these results, interpreted with the support of chemometric methods, also reveals the limitations of this PBA, probably related to the deactivation of the Mn undergoing extensive reversible Jahn-Teller distortion during cycling as well as possible dissolution in the electrolyte. These results underline that optimisation of the chemical composition of PBAs is a crucial step towards the preparation of reliable and stable PBA-based cathodes for PIBs.

Published
2023

10. Investigating the Cycling Stability of Fe2WO6 Pseudocapacitive Electrode Materials

Author

Julio César Espinosa-Angeles, Nicolas Goubard-Bretesché, Eric Quarez, Christophe Payen, Moulay-Tahar Sougrati, Olivier Crosnier, and Thierry Brousse

Subjects
Fe2WO6, electrochemical capacitor, pseudocapacitance, Mössbauer spectroscopy, Chemistry, QD1-999
Abstract

The stability upon cycling of Fe2WO6 used as a negative electrode material for electrochemical capacitors was investigated. The material was synthesized using low temperature conditions for the first time (220 °C). The electrochemical study of Fe2WO6 in a 5 M LiNO3 aqueous electrolyte led to a specific and volumetric capacitance of 38 F g−1 and 240 F cm−3 when cycled at 2 mV·s−1, respectively, associated with a minor capacitance loss after 10,000 cycles. In order to investigate this very good cycling stability, both surface and bulk characterization techniques (such as Transmission Electron Microscopy, Mössbauer spectroscopy, and magnetization measurements) were used. Only a slight disordering of the Fe3+ cations was observed in the structure, explaining the good stability of the Fe2WO6 upon cycling. This study adds another pseudocapacitive material to the short list of compounds that exhibit such a behavior up to now.

Published
2021
Full Text
View/download PDF

11. Structural and Reactivity Effects of Secondary Metal Doping into Iron-Nitrogen-Carbon Catalysts for Oxygen Electroreduction

Author

Frédéric Jaouen, Fang Luo, Aaron Roy, Moulay Tahar Sougrati, Anastassiya Khan, David Cullen, Xingli Wang, Mathias Primbs, Andrea Zitolo, and Peter Strasser

Abstract

While improved activity was recently reported for bimetallic iron-metal-nitrogen-carbon (FeMNC) catalysts for the oxygen reduction reaction (ORR) in acid medium, the nature of active sites and interactions between the two metals are poorly understood. Here, FeSnNC and FeCoNC catalysts were structurally and catalytically compared to their parent FeNC and SnNC catalysts. While CO cryo-chemisorption revealed a twice lower site density of M-Nx sites for FeSnNC and FeCoNC relative to FeNC and SnNC, the mass activity of both bimetallic catalysts is 50–100% higher than that of FeNC, due to a larger turnover frequency in the bimetallic catalysts. Electron microscopy and X-ray absorption spectroscopy identified the coexistence of Fe-Nx and Sn-Nx or Co-Nx sites, while no evidence was found for binuclear Fe-M-Nx sites. 57Fe Mössbauer spectroscopy revealed that the bimetallic catalysts feature a higher D1/D2 ratio of the spectral signatures assigned to two distinct Fe-Nx sites, relative to the FeNC parent catalyst. Thus, the addition of the secondary metal favored the formation of D1 sites, associated with the higher turnover frequency.

Published
2023

12. In situ/operando Mössbauer spectroscopy for probing heterogeneous catalysis

Author

Moulay Tahar Sougrati, Junhu Wang, Bin Liu, Yanqiang Huang, Yaqiong Zeng, Xuning Li, and Tao Zhang

Subjects
In situ, Reaction conditions, Electrode material, Materials science, Chemistry (miscellaneous), Organic Chemistry, Mössbauer spectroscopy, Nanotechnology, Physical and Theoretical Chemistry, Electrocatalyst, Heterogeneous catalysis, Catalysis, Sustainable energy
Abstract

Summary In situ/operando Mossbauer spectroscopy is one of the most powerful techniques to quantitatively monitor the coordination and electronic structure of Mossbauer isotopes (119Sn, 57Fe, etc.) contained in heterogeneous catalysts under practical reaction conditions. To promote further progress in identifying the real structure of catalytic site(s) and revealing the underlying catalytic mechanism, herein we thoroughly summarize the recent advances of in situ/operando Mossbauer technique for probing heterogeneous catalysts and electrode materials for sustainable energy applications, including electrocatalysis, thermocatalysis, Li-ion batteries, etc. The unique role of this technique in different catalytic system is discussed with emphasis placed on several typical research advances. Moreover, the recent emerging operando Mossbauer technique for the study of single-atom catalysts, which is considered as a new eye for providing electronic-level insight into catalytic mechanism, is highlighted. Finally, the outlooks and challenges are discussed toward further application and rising influence of in situ/operando Mossbauer spectroscopy in heterogeneous catalysis.

Published
2021

13. Engineering of Iron-Based Magnetic Activated Carbon Fabrics for Environmental Remediation

Author

Hai Haham, Judith Grinblat, Moulay-Tahar Sougrati, Lorenzo Stievano, and Shlomo Margel

Subjects
thermal decomposition, iron nanoparticles, iron oxide nanoparticles, magnetic nanomaterials, carbon fabrics, environmental remediation, Technology, Electrical engineering. Electronics. Nuclear engineering, TK1-9971, Engineering (General). Civil engineering (General), TA1-2040, Microscopy, QH201-278.5, Descriptive and experimental mechanics, QC120-168.85
Abstract

Magnetic Fe3O4, Fe and Fe/Pd nanoparticles embedded within the pores of activated carbon fabrics (ACF) were prepared by impregnation of the ACF in iron acetylacetanoate (Fe(acac)3) ethanol solution, followed by thermal decomposition of the embedded iron precursor at 200, 400 and 600 °C in an inert atmosphere. The effect of the annealing temperature on the chemical composition, shape, crystallinity, surface area, pore volume, and magnetic properties of the various functionalized ACF was elucidated. The Fe nanoparticles within the ACF were also doped with tinier Pd nanoparticles, by impregnation of the Fe/ACF in palladium acetate ethanol solution. The potential use of the functionalized ACF for removal of a model azo-dye, orange II, was demonstrated. This study illustrated the enhanced removal of the dye from an aqueous solution according to the following order: Fe/Pd/ACF > Fe/ACF > ACF. In addition, the enhanced activity of Fe3O4/ACF in the presence of increasing concentrations of H2O2 (Fenton catalysts) was also illustrated.

Published
2015
Full Text
View/download PDF

14. Unraveling the complex causality behind the Fe-N-C degradation in fuel cell

Author

Geunsu Bae, Song Jin, Man Ho Han, Hyung-Suk Oh, Moulay Tahar Sougrati, Kug-Seung Lee, Min Ho Seo, Frédéric Jaouen, and Chang Hyuck Choi

Abstract

Beyond great advances in initial activity, Fe-N-C catalysts face the next challenge of stability issue in acidic medium that must be overcome to replace Pt in fuel cell cathode. However, the complex phenomena in fuel cells and consequential difficulty in understanding deactivation mechanisms of Fe-N-C cathodes impede solutions for prolonged stability. Here, we show time-resolved changes in active site density (SD) and turnover frequency (TOF) of Fe-N-C along with concurrent decrease in oxygen reduction reaction (ORR) current in temperature/gas controllable gas-diffusion electrode (GDE) flow cell. In operando diagnosis of Fe leaching identifies a strong dependence of SD changes on operating parameters, and draws a lifetime-dependent stability diagram that reveals a shift in prime degradation mechanism during the operations. A proof-of-concept strategy with site-isolated Pt ions as a non-catalytic stabilizer, supported by theoretical calculation, demonstrates enhanced fuel cell stability with reduced Fe dissolution, offering new design principle for durable Fe-N-C catalysts.

Published
2022

16. Chemical vapour deposition of Fe–N–C oxygen reduction catalysts with full utilization of dense Fe–N4 sites

Author

Moulay Tahar Sougrati, Deborah J. Myers, Qingying Jia, Sichen Zhong, Jingkun Li, Magali Ferrandon, Fan Yang, Yu Huang, Sanjeev Mukerjee, Li Jiao, Qiang Sun, Ershuai Liu, Thomas Stracensky, David A. Cullen, Hui Xu, Jaehyung Park, Frédéric Jaouen, Lynne Larochelle Richard, Zipeng Zhao, Northeastern University [Boston], Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and Argonne National Laboratory [Lemont] (ANL)

Subjects
Inorganic chemistry, chemistry.chemical_element, Proton exchange membrane fuel cell, 02 engineering and technology, Chemical vapor deposition, 010402 general chemistry, 01 natural sciences, Redox, Catalysis, General Materials Science, biology, Mechanical Engineering, Substrate (chemistry), Active site, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Oxygen reduction, 0104 chemical sciences, chemistry, Mechanics of Materials, biology.protein, 0210 nano-technology, Platinum
Abstract

Replacing scarce and expensive platinum (Pt) with metal–nitrogen–carbon (M–N–C) catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells has largely been impeded by the low oxygen reduction reaction activity of M–N–C due to low active site density and site utilization. Herein, we overcome these limits by implementing chemical vapour deposition to synthesize Fe–N–C by flowing iron chloride vapour over a Zn–N–C substrate at 750 °C, leading to high-temperature trans-metalation of Zn–N4 sites into Fe–N4 sites. Characterization by multiple techniques shows that all Fe–N4 sites formed via this approach are gas-phase and electrochemically accessible. As a result, the Fe–N–C catalyst has an active site density of 1.92 × 1020 sites per gram with 100% site utilization. This catalyst delivers an unprecedented oxygen reduction reaction activity of 33 mA cm−2 at 0.90 V (iR-corrected; i, current; R, resistance) in a H2–O2 proton exchange membrane fuel cell at 1.0 bar and 80 °C. Replacing platinum with metal–nitrogen–carbon catalysts for the oxygen reduction reaction in proton exchange membrane fuel cells has been impeded by low activity. These limitations have now been overcome by the trans-metalation of Zn–N4 sites into Fe–N4 sites.

Published
2021

17. Triggering Anionic Redox Activity in Li 3 NbS 4 Through Cationic Disordering or Substitution

Author

Thomas Marchandier, Sathiya Mariyappan, Maria A. Kirsanova, Artem M. Abakumov, Gwenaëlle Rousse, Dominique Foix, Moulay‐Tahar Sougrati, Marie Liesse Doublet, Jean‐Marie Tarascon, 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), Skolkovo Institute of Science and Technology [Moscow] (Skoltech), Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Réseau sur le stockage électrochimique de l'énergie (RS2E), Aix Marseille Université (AMU)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Nantes Université (Nantes Univ)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Collège de France - Chaire Chimie du solide et énergie, Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), European Project: 670116,H2020,ERC-2014-ADG,ARPEMA(2015), and Chaire Chimie du solide et énergie

Subjects
Renewable Energy, Sustainability and the Environment, crystal- electronic structure relationship, cation substitution, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [CHIM]Chemical Sciences, Li-ion batteries, General Materials Science, disordered rock-salt phases, [CHIM.MATE]Chemical Sciences/Material chemistry, anionic redox
Abstract

International audience; Extensive utilization of Li-ion batteries for varieties of applications necessitates ceaseless improvements of electrode materials for achieving higher energy density. Towards this goal, Li-rich layered oxides exhibiting high capacity due to cumulated cationic and anionic redox activities are under study for nearly a decade. Still, several unanswered questions remain with respect to these Li-driven anionic redox reactions in terms of the activation process and long-term consequences upon cycling. Here, the Li-rich Li3NbS4 phase is focused, and synthesized as two different polymorphs, namely ordered and disordered phases. From analyses of their chemical and electrochemical properties, a crystal-electronic structure relationship is unraveled that triggers the anionic redox activity in these compounds. Moreover, through complementary theoretical calculations, the capability of cationic disorder to trigger anionic redox activity via the hybridization of cationic and non-bonding anionic energy levels is shown. This finding is further supported by the appearance of anionic redox activity by introducing the disorder through cationic substitution. Altogether, the insights derived can help in designing new anionic redox materials with optimum performances for practical applications.

Published
2022

18. The Challenge of Achieving a High Density of Fe-Based Active Sites in a Highly Graphitic Carbon Matrix

Author

Jingkun Li, Qingying Jia, Sanjeev Mukerjee, Moulay-Tahar Sougrati, Goran Drazic, Andrea Zitolo, and Frédéric Jaouen

Subjects
oxygen reduction reaction, Fe–N–C, active site, graphitic carbon, Chemical technology, TP1-1185, Chemistry, QD1-999
Abstract

As one of the most promising platinum group metal-free (PGM-free) catalysts for oxygen reduction reaction (ORR), Fe⁻N⁻C catalysts with a high density of FeNx moieties integrated in a highly graphitic carbon matrix with a proper porous structure have attracted extensive attention to combine the high activity, high stability and high accessibility of active sites. Herein, we investigated a ZnCl2/NaCl eutectic salts-assisted ionothermal carbonization method (ICM) to synthesize Fe⁻N⁻C catalysts with tailored porous structure, high specific surface area and a high degree of graphitization. However, it was found to be challenging to anchor a high density of FeNx sites onto highly graphitized carbon. Iron precursors with preexisting Fe⁻N coordination were required to form FeNx sites in the nitrogen-doped carbon with a high degree of graphitization, while individual Fe and N precursors led to a Fe⁻N⁻C catalyst with poor-ORR activity. This provides valuable insights into the synthesis-structure relationship. Moreover, the FeNx moieties were identified as the major active sites in acidic conditions, while both FeNx sites and Fe2O3 were found to be active in alkaline medium.

Published
2019
Full Text
View/download PDF

20. Magnetism and hyperfine interactions in the hexagonal polymorph of delafossite CuFeO2

Author

Benedikt Klobes, Manuel Angst, Daniela Fenske, Chinmay M. Konnur, Abdelfattah Mahmoud, Moulay Tahar Sougrati, Jülich Centre for Neutron Science (JCNS), Jülich Centre for Neutron Science (JCNS - PGI, JARA-FIT), Peter Grünberg Institut (PGI), Group of Research in Energy and ENvironment from MATerials (GREENMAT), Université de Liège, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Advanced Lithium Energy Storage Systems - ALISTORE-ERI (ALISTORE-ERI), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Aix Marseille Université (AMU)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), and Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Nantes Université (Nantes Univ)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)

Subjects
[CHIM]Chemical Sciences, ddc:530, Condensed Matter Physics, Electronic, Optical and Magnetic Materials
Abstract

Journal of magnetism and magnetic materials 570, 170469 - (2023). doi:10.1016/j.jmmm.2023.170469, The magnetic susceptibility of and hyperfine interactions in the hexagonal 2H polymorph of delafossite CuFeO were investigated by SQUID magnetometry and Mössbauer spectroscopy, respectively, at low temperatures. The hydrothermally synthesized 2H-CuFeO sample contained a 10 vol-% -FeO impurity detected by X-ray diffraction, whose contribution to the susceptibility and hyperfine interactions were easily distinguishable from the major 2H-CuFeO one. Morphology and indirect optical band gap investigated by scanning electron microscopy and diffuse reflectance measurements showed well expected results for a hydrothermally synthesized delafossite sample. The magnetic susceptibility of 2H-CuFeO revealed a first antiferromagnetic like transitions at 16 K and a second transition at 13.5 K or 10 K depending on measurement protocol, which points towards modified exchange interactions as compared to the 3R polymorph. Complementary Mössbauer measurements revealed complicated spectral shapes at low temperatures indicating rather complex magnetic structures and magnetic relaxations above 20 K., Published by North-Holland Publ. Co., Amsterdam

Published
2023

22. High loading of single atomic iron sites in Fe-NC oxygen reduction catalysts for proton exchange membrane fuel cells

Author

Asad Mehmood, Mengjun Gong, Frédéric Jaouen, Aaron Roy, Andrea Zitolo, Anastassiya Khan, Moulay-Tahar Sougrati, Mathias Primbs, Alex Martinez Bonastre, Dash Fongalland, Goran Drazic, Peter Strasser, Anthony Kucernak, Engineering & Physical Science Research Council (E, and Commission of the European Communities

Subjects
CONDENSED MATTER, Science & Technology, Chemistry, Physical, Process Chemistry and Technology, Bioengineering, PERFORMANCE, Biochemistry, Catalysis, NITROGEN-CARBON CATALYSTS, Chemistry, DOPED CARBON, TURNOVER FREQUENCY, METAL, Physical Sciences, RAY-ABSORPTION SPECTROSCOPY, BODY DISTRIBUTION-FUNCTIONS, C CATALYSTS, ACTIVE-SITES
Abstract

Non-precious iron-based catalysts (Fe-NCs) require high active site density (SD) to meet the performance targets as cathode catalysts in proton exchange membrane fuel cells (PEMFCs). SD is generally limited to that achieved at 1-3 wt%(Fe) loading due to the undesired formation of iron-containing nanoparticles at higher loadings. Here we show that by pre-forming a carbon-nitrogen matrix using a sacrificial metal (Zn) in the initial synthesis step and then exchanging iron into this preformed matrix we achieve 7 wt% iron coordinated solely as single atom Fe-N4 sites as identified by 57Fe cryo Mössbauer spectroscopy and X-ray absorption spectroscopy. SD values measured by in situ nitrite stripping and ex situ CO chemisorption methods are 4.7x1019 and 7.8x1019 sitesg-1, with a turnover frequency of 5.4 electrons̭sites-1s-1 at 0.80 V in 0.5M H2SO4 electrolyte. The catalyst delivers excellent PEMFC performance with current densities of 41.3 mAcm-2 at 0.90 ViR-free using H2-O2 (10.6 Ag-1) and 145 mA cm-2 at 0.80 V (199 mAcm-2 at 0.80 ViR-free) using H2-air.

Published
2022

23. Establishing reactivity descriptors for platinum group metal (PGM)-free Fe–N–C catalysts for PEM fuel cells

Author

Moulay Tahar Sougrati, Giorgia Daniel, Tomasz Kosmala, Christian Durante, Asad Mehmood, Aaron Roy, Peter Strasser, Mathias J.M. Primbs, Yanyan Sun, Daniel Malko, Frédéric Jaouen, Jonathan Sharman, Gaetano Granozzi, Pierre-Yves Blanchard, Plamen Atanassov, Anthony Kucernak, Deborah J. Jones, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Center For Emerging Energy Technologies [Albuquerque] (CEET), The University of New Mexico [Albuquerque], Department of Chemistry [Imperial College London], Imperial College London, Technische Universität Berlin (TU), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2), Department of Chemical Sciences, Universita degli Studi di Padova, Johnson Matthey Technology Centre, and Commission of the European Communities

Subjects
Inorganic chemistry, Proton exchange membrane fuel cell, Context (language use), 02 engineering and technology, 010402 general chemistry, Electrochemistry, 01 natural sciences, Catalysis, [CHIM]Chemical Sciences, Environmental Chemistry, Reactivity (chemistry), ComputingMilieux_MISCELLANEOUS, Energy, Renewable Energy, Sustainability and the Environment, Chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, Microporous material, 021001 nanoscience & nanotechnology, Pollution, 0104 chemical sciences, Nuclear Energy and Engineering, 13. Climate action, Chemisorption, ddc:540, 0210 nano-technology, Mesoporous material
Abstract

International audience; We report a comprehensive analysis of the catalytic oxygen reduction reaction (ORR) reactivity of four of today's most active benchmark platinum group metal-free (PGM-free) iron/nitrogen doped carbon electrocatalysts (Fe-N-Cs). Our analysis reaches far beyond previous such attempts in linking kinetic performance metrics, such as electrocatalytic mass-based and surface area-based catalytic activity with previously elusive kinetic metrics such as the active metal site density (SD) and the catalytic turnover frequency (TOF). Kinetic ORR activities, SD and TOF values were evaluated using in situ electrochemical NO 2 À reduction as well as an ex situ gaseous CO cryo chemisorption. Experimental ex situ and in situ Fe surface site densities displayed remarkable quantitative congruence. Plots of SD versus TOF (''reactivity maps'') are utilized as new analytical tools to deconvolute ORR reactivities and thus enabling rational catalyst developments. A microporous catalyst showed large SD values paired with low TOF, while mesoporous catalysts displayed the opposite. Trends in Fe surface site density were linked to molecular nitrogen and Fe moieties (D1 and D2 from 57 Fe Mössbauer spectroscopy), from which pore locations of catalytically active D1 and D2 sites were established. This cross-laboratory analysis, its employed experimental practices and analytical methodologies are expected to serve as a widely accepted reference for future, knowledge-based research into improved PGM-free fuel cell cathode catalysts. Broader context Polymer electrolyte membrane fuel cells (PEMFC) have reached the commercial stage and ever wider deployment is imminent. To further reduce the loading of platinum group metal (PGM) catalysts in PEMFC electrodes, PGM-free, iron and nitrogen-doped carbon oxygen reduction (ORR) electrocatalysts (Fe-N-C) were developed over past decades. Recent advances in activity and stability of Fe-N-C are impressive, yet methods to evaluate the number of catalytic active Fe sites at the surface and intrinsic turn over frequency remained elusive. This changed with the advent of CO cryo-sorption and in situ nitrite stripping techniques that yielded these intrinsic reactivity descriptors. Never before, however, have these two complementary specific adsorption/stripping techniques been compared and combined with other chemical and spectroscopic analytics for an in-depth analysis of catalytic reactivity of Fe-N-C ORR electrocatalysts. The present study addresses this issue and presents a comprehensive analysis of the reactivity of the four state-of-the-art Fe-N-C PEMFC electrocatalysts. The study provides a deeper understanding of the origin and difference in catalytic performance through the combination of a host of different surface sensitive and bulk analysis methods. The methodologies and analyses of this benchmark catalyst study will benefit future developments in Fe-N-C catalysis.

Published
2020

24. Unveiling redox mechanism at the iron centers in the mechanochemically activated conversion of CO2 in the presence of olivine

Author

Valeria Farina, Maria Domenica Simula, Alessandro Taras, Luca Cappai, Moulay Tahar Sougrati, Gabriele Mulas, Sebastiano Garroni, Stefano Enzo, and Lorenzo Stievano

Subjects
Mechanics of Materials, Mechanical Engineering, General Materials Science
Abstract

The transformation of olivine during the conversion of CO2 to light hydrocarbons activated by mechanochemical treatments at different impact frequencies was studied by a combination of several complementary characterization methods including X-ray diffraction, Raman and 57Fe Mössbauer spectroscopy. Several olivine samples were studied as a function of the milling time, indicating the gradual transformation of FeII-containing olivine into new FeIII-containing weathering products including iron oxides, magnesium iron carbonates and silicates. The results presented here complement those of a previous study on the weathering process of olivine promoted by mechanochemical activation, by demonstrating the role of the redox activity of the iron species during the activation process. These additional spectroscopic results allow us to thoroughly understand the complex weathering mechanism and to correlate it with the efficiency of the CO2 conversion and storage properties of mechanochemically activated olivine.

Published
2022

25. From Na2FePO4F/CNT to NaKFePO4F/CNT as advanced cathode material for K-ion batteries

Author

Jérôme Bodart, Nicolas Eshraghi, Moulay Tahar Sougrati, Frédéric Boschini, Pierre-Emmanuel Lippens, Bénédicte Vertruyen, and Abdelfattah Mahmoud

Subjects
Renewable Energy, Sustainability and the Environment, Energy Engineering and Power Technology, Electrical and Electronic Engineering, Physical and Theoretical Chemistry
Published
2023

27. Si/Cu-Zn(ox)/C composite as anode material for Li-ion batteries

Author

Moulay Tahar Sougrati, Pierre-Emmanuel Lippens, Zhongbin Ye, Mohamad Chamas, Yawen He, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and School of Chemistry and Chemical Engineering, Southwest Petroleum University

Subjects
Materials science, Composite number, Nanoparticle, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, General Chemistry, Electrolyte, Carbon black, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electrochemistry, 01 natural sciences, 7. Clean energy, 0104 chemical sciences, Dielectric spectroscopy, Anode, Chemical engineering, [CHIM]Chemical Sciences, General Materials Science, 0210 nano-technology, Ball mill, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; The silicon based composite Si/Cu-Zn(ox)/C was prepared by ball milling from Si microparticles, Cu Zn nanopowder heated at air and carbon black. The composite is formed by Si submicrometer particles, Cu-rich Cu x Zn, CuO, ZnO and C nanoparticles. The two oxides are electrochemically active during the first discharge, improving the nanostructuration of the composite and providing Cu nanoparticles that enhance the electronic conductivity with Cu x Zn and C. The nanostructuration helps to buffer the volume variations due to Li Si alloying reactions during cycling. The composite is further nanostructured during the first cycles as shown by XRD and electrochemical measurements. The material was tested as anode material for Li-ion batteries, providing a reversible capacity of 800 mAh.g −1 during 100 cycles at current of 300 mA.g −1 and a good rate capability. The reversible capacity is mainly due to Li Si alloying reactions and is stable after few cycles while the solid electrolyte interphase is stabilized after about ten cycles as shown by electrochemical impedance spectroscopy.

Published
2021

28. In situ high temperature XRD study of Sr-doped ceramics La0.95Sr0.05MnO3+δ

Author

Moulay Tahar Sougrati, Oxana Rybchenko, Bernard Fraisse, V. D. Sedykh, D. I. Pchelina, Lomonosov Moscow State University (MSU), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
In situ, Phase transition, Materials science, Analytical chemistry, chemistry.chemical_element, 02 engineering and technology, 01 natural sciences, Oxygen, chemistry.chemical_compound, Lanthanum manganite, Lattice (order), 0103 physical sciences, Materials Chemistry, [CHIM]Chemical Sciences, Thermal stability, Ceramic, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Doping, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, chemistry, visual_art, visual_art.visual_art_medium, 0210 nano-technology
Abstract

Sr-doped lanthanum manganite La0.95Sr0.05MnO3+δ powder was obtained by sol-gel method. The effect of heating behavior and the effect of interstitial oxygen on structural properties of the LSMO ceramics were studied by XRD, including high-temperature in situ measurements (150–6500С). The as prepared powder is single-phase and has a rhombohedral structure (R-3c space group). In situ XRD results showed that heating under vacuum does not lead to a structure change; which remains rhombohedral. However, with an increase of temperature, the lattice parameters increase, reflecting a decrease of interstitial oxygen fraction. In addition, rhombohedral angle α decreases, which indicates that the lattice tends to cubic. Comparison of the studied sample with the La0.95Sr0.05MnO3 annealed in vacuum under special conditions has been carried out. Thermal stability of the material under heating and vacuum, which did not lead to the expected phase transition, was revealed. The necessary conditions for obtaining oxygen stoichiometry are given in work.

Published
2021

29. Correlating ligand-to-metal charge transfer with voltage hysteresis in a Li-rich rock-salt compound exhibiting anionic redox

Author

Artem M. Abakumov, Rémi Dedryvère, Gwenaëlle Rousse, Jean-Marie Tarascon, Marie-Liesse Doublet, Moulay Tahar Sougrati, Anatoliy Senyshyn, Biao Li, Antonella Iadecola, Anatolii V. Morozov, Leiting Zhang, Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux (IPREM), Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and Collège de France (CdF (institution))

Subjects
General Chemical Engineering, Salt (chemistry), 02 engineering and technology, 010402 general chemistry, 01 natural sciences, Redox, law.invention, Metal, law, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Lone pair, chemistry.chemical_classification, Chemistry, Ligand, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Cathode, 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, Hysteresis, [CHIM.POLY]Chemical Sciences/Polymers, Octahedron, Chemical physics, visual_art, visual_art.visual_art_medium, 0210 nano-technology
Abstract

Anionic redox is a double-edged sword for Li-ion cathodes because it offers a transformational increase in energy density that is also negated by several detrimental drawbacks to its practical implementation. Among them, voltage hysteresis is the most troublesome because its origin is still unclear and under debate. Herein, we tackle this issue by designing a prototypical Li-rich cation-disordered rock-salt compound Li1.17Ti0.33Fe0.5O2 that shows anionic redox activity and exceptionally large voltage hysteresis while exhibiting a partially reversible Fe migration between octahedral and tetrahedral sites. Through combined in situ and ex situ spectroscopic techniques, we demonstrate the existence of a non-equilibrium (adiabatic) redox pathway enlisting Fe3+/Fe4+ and O redox as opposed to the equilibrium (non-adiabatic) redox pathway involving sole O redox. We further show that the charge transfer from O(2p) lone pair states to Fe(3d) states involving sluggish structural distortion is responsible for voltage hysteresis. This study provides a general understanding of various voltage hysteresis signatures in the large family of Li-rich rock-salt compounds. The use of anionic redox chemistry in high-capacity Li-rich cathodes is being hampered by voltage hysteresis, the origin of which remains obscure. Now it has been shown that sluggish ligand-to-metal charge transfer kinetically traps an intermediate Fe4+ species and is responsible for voltage hysteresis in the prototypical Li-rich cation-disordered rock-salt Li1.17Ti0.33Fe0.5O2.

Published
2021

30. Électrodes négatives non carbonées pour batteries au sodium

Author

Lorenzo Stievano, Moulay Tahar Sougrati, Vincent Gabaudan, and Laure Monconduit

Abstract

La chimie et la conception des matériaux non carbonés d'électrode négative sont décrites dans ce chapitre. Ils se répartissent en trois groupes selon le mécanisme de stockage du sodium : les matériaux d’insertion, les matériaux d’alliage et les matériaux de conversion. Ces mécanismes électrochimiques sont ici rappelés dans le cas du sodium. Chacun de ces groupes présente des avantages et inconvénients pour l’application des batteries qui sont déclinés dans ce chapitre.

Published
2021

31. Author Correction: P-block single-metal-site tin/nitrogen-doped carbon fuel cell cathode catalyst for oxygen reduction reaction

Author

Fang Luo, Aaron Roy, Luca Silvioli, David A. Cullen, Andrea Zitolo, Moulay Tahar Sougrati, Ismail Can Oguz, Tzonka Mineva, Detre Teschner, Stephan Wagner, Ju Wen, Fabio Dionigi, Ulrike I. Kramm, Jan Rossmeisl, Frédéric Jaouen, and Peter Strasser

Subjects
Mechanics of Materials, Mechanical Engineering, General Materials Science, General Chemistry, Condensed Matter Physics
Published
2022

32. Metal Oxide Clusters on Nitrogen-Doped Carbon are Highly Selective for CO2Electroreduction to CO

Author

Tristan Asset, Jingkun Li, Frédéric Jaouen, José Ramón Galán-Mascarós, Pengyi Tang, Jordi Arbiol, Felipe A. Garcés-Pineda, Iryna V. Zenyuk, Plamen Atanassov, Moulay Tahar Sougrati, Mounika Kodali, Andrea Zitolo, European Commission, Ministerio de Ciencia, Innovación y Universidades (España), Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institute of Chemical Research of Catalonia (ICIQ), The University of New Mexico [Albuquerque], Departament d'Electrònica (EME/CeRMAE/IN2UB), Universitat de Barcelona (UB), University of California [Irvine] (UCI), and University of California

Subjects
Inorganic chemistry, Oxide, chemistry.chemical_element, Nitrogen doped, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, 7. Clean energy, Catalysis, Metal, chemistry.chemical_compound, [CHIM]Chemical Sciences, Materials, ComputingMilieux_MISCELLANEOUS, Catalysts, General Chemistry, Transition metals, 021001 nanoscience & nanotechnology, Highly selective, X-ray absorption near edge spectroscopy, 0104 chemical sciences, chemistry, Metals, visual_art, visual_art.visual_art_medium, 0210 nano-technology, Carbon
Abstract

The electrochemical reduction of CO2 (eCO2RR) using renewable energy is an effective approach to pursue carbon neutrality. The eCO2RR to CO is indispensable in promoting C-C coupling through bifunctional catalysis and achieving cascade conversion from CO2 to C2+. This work investigates a series of M/N-C (M = Mn, Fe, Co, Ni, Cu, and Zn) catalysts, for which the metal precursor interacted with the nitrogen-doped carbon support (N-C) at room temperature, resulting in the metal being present as (sub)nanosized metal oxide clusters under ex situ conditions, except for Cu/N-C and Zn/N-C. A volcano trend in their activity toward CO as a function of the group of the transition metal is revealed, with Co/N-C exhibiting the highest activity at -0.5 V versus RHE, while Ni/N-C shows both appreciable activity and selectivity. Operando X-ray absorption spectroscopy shows that the majority of Cu atoms in Cu/N-C form Cu0 clusters during eCO2RR, while Mn/, Fe/, Co/, and Ni/N-C catalysts maintain the metal hydroxide structures, with a minor amount of M0 formed in Fe/, Co/, and Ni/N-C. The superior activity of Fe/, Co/, and Ni/N-C is ascribed to the phase contraction and the HCO3- insertion into the layered structure of metal hydroxides. Our work provides a facile synthetic approach toward highly active and selective electrocatalysts to convert CO2 into CO. Coupled with state-of-the-art NiFe-based anodes in a full-cell device, Ni/N-C exhibits >80% Faradaic efficiency toward CO at 100 mA cm-2., The research leading to these results has received funding from the A-LEAF Project, which is funded by the European Union’s H2020 Programme under grant agreement no. 732840. ICN2 and ICIQ acknowledge funding from the FEDER/Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación (projects ENE2017-85087-C3 and RTI2018-095618-B-I00) and the Generalitat de Catalunya (2017 SGR 327 and 2017- SGR-1406) and by the CERCA Programme / Generalitat de Catalunya. ICN2 and ICIQ are supported by the Severo Ochoa program from Spanish MINECO (grants no. SEV-2017-0706 and CEX2019-000925-S).

Published
2021

33. Effect of Ball-Milling on the Oxygen Reduction Reaction Activity of Iron and Nitrogen Co-doped Carbide-Derived Carbon Catalysts in Acid Media

Author

Väino Sammelselg, Maido Merisalu, Moulay Tahar Sougrati, Mihkel Rähn, Maike Käärik, Arvo Kikas, Sander Ratso, Päärn Paiste, Kaido Tammeveski, Jaan Leis, Vambola Kisand, Frédéric Jaouen, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Materials science, Energy Engineering and Power Technology, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, Electrocatalyst, 01 natural sciences, 7. Clean energy, Catalysis, Metal, Materials Chemistry, Electrochemistry, Chemical Engineering (miscellaneous), Electrical and Electronic Engineering, Ball mill, ComputingMilieux_MISCELLANEOUS, [CHIM.CATA]Chemical Sciences/Catalysis, 021001 nanoscience & nanotechnology, Nitrogen, 0104 chemical sciences, chemistry, Chemical engineering, visual_art, visual_art.visual_art_medium, Carbide-derived carbon, 0210 nano-technology, Carbon, Co doped
Abstract

Iron- and nitrogen-doped carbon-based catalysts are one of the most promising alternatives to platinum-group metal-based ones currently used in the fuel cell industry. Here, we study the effect of ...

Published
2019

34. Designing the 3D Architecture of PGM-Free Cathodes for H2/Air Proton Exchange Membrane Fuel Cells

Author

Jingkun Li, Sara Cavaliere, Dinesh C. Sabarirajan, Sebastian Brüller, Moulay Tahar Sougrati, Deborah J. Jones, Andrea Zitolo, Frédéric Jaouen, Nastaran Ranjbar-Sahraie, Iryna V. Zenyuk, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), and ANR-16-CE05-0007,CAT2CAT,Des catalyseurs aux cathodes: Une approche d'architecture contrôlée d'électrode pour pile PEM à base de métaux abondants(2016)

Subjects
inorganic chemicals, Mass transport, Materials science, Energy Engineering and Power Technology, Proton exchange membrane fuel cell, 02 engineering and technology, 010402 general chemistry, 7. Clean energy, 01 natural sciences, law.invention, Catalysis, law, Materials Chemistry, Electrochemistry, Chemical Engineering (miscellaneous), Oxygen reduction reaction, Electrical and Electronic Engineering, ComputingMilieux_MISCELLANEOUS, organic chemicals, [CHIM.CATA]Chemical Sciences/Catalysis, 021001 nanoscience & nanotechnology, Cathode, Electrospinning, 0104 chemical sciences, Chemical engineering, 0210 nano-technology
Abstract

Metal–nitrogen–carbon catalysts have emerged as the most promising platinum group metal-free catalysts toward oxygen reduction reaction for proton exchange membrane fuel cell (PEMFC) applications. ...

Published
2019

35. An oxalate cathode for lithium ion batteries with combined cationic and polyanionic redox

Author

Hui-Ming Cheng, Philip Lightfoot, Suchinda Sattayaporn, Chenghua Sun, Xiaolong Zhou, Wenjiao Yao, Moulay Tahar Sougrati, Chunlei Jiang, Yongbing Tang, Nanzhong Wu, A. Robert Armstrong, Bifa Ji, Sarayut Tunmee, Pinit Kidkhunthod, University of St Andrews. School of Chemistry, University of St Andrews. EaSTCHEM, School of Chemistry [University of St Andrews], University of St Andrews [Scotland], Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Shenyang National Laboratory for Materials Science, Institute of Metal Research [Chinese Academy of Sciences] (IMR), and Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS)

Subjects
0301 basic medicine, Science, Inorganic chemistry, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, 7. Clean energy, Redox, General Biochemistry, Genetics and Molecular Biology, Oxalate, Article, law.invention, Ion, 03 medical and health sciences, chemistry.chemical_compound, Batteries, law, QD, SDG 7 - Affordable and Clean Energy, lcsh:Science, R2C, Electrode material, Multidisciplinary, Chemistry, Gas evolution reaction, Cationic polymerization, DAS, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, QD Chemistry, Cathode, 030104 developmental biology, Lithium, lcsh:Q, 0210 nano-technology, BDC
Abstract

The growing demand for advanced lithium-ion batteries calls for the continued development of high-performance positive electrode materials. Polyoxyanion compounds are receiving considerable interest as alternative cathodes to conventional oxides due to their advantages in cost, safety and environmental friendliness. However, polyanionic cathodes reported so far rely heavily upon transition-metal redox reactions for lithium transfer. Here we show a polyanionic insertion material, Li2Fe(C2O4)2, in which in addition to iron redox activity, the oxalate group itself also shows redox behavior enabling reversible charge/discharge and high capacity without gas evolution. The current study gives oxalate a role as a family of cathode materials and suggests a direction for the identification and design of electrode materials with polyanionic frameworks., Polyoxyanion compounds are alternative cathodes to conventional oxides, but their reliance on the transition metal redox limits the performance. Here the authors report an oxalate system which possesses additional polyanionic redox reactivity, suggesting a new direction for cathode materials design.

Published
2019

36. Revisiting the Phase Transition of Magnetite under Pressure

Author

Zhiwei Hu, Moulay Tahar Sougrati, Kai Chen, Alexander C. Komarek, Qingyu Kong, Yimin Mijiti, A. Di Cicco, F. Baudelet, L. Nataf, Julien Haines, Jérôme Rouquette, Stefano Agrestini, Tsu-Chien Weng, Center for High Pressure Science & Technology Advanced Research (HPSTAR), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), University of Camerino, Max Planck Institute for Chemical Physics of Solids (CPfS), Max-Planck-Gesellschaft, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Phase transition, Materials science, Condensed matter physics, Magnetic moment, Magnetic circular dichroism, 02 engineering and technology, Dichroism, 021001 nanoscience & nanotechnology, 01 natural sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, chemistry.chemical_compound, General Energy, chemistry, Spin crossover, Phase (matter), 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [CHIM]Chemical Sciences, Orthorhombic crystal system, Physical and Theoretical Chemistry, 010306 general physics, 0210 nano-technology, Magnetite
Abstract

International audience; Using a highly stoichiometric magnetite, the pressure-induced phase transitions of Fe3O4 have been revisited here by performing Fe K-edge X-ray absorption and magnetic circular dichroism measurements up to P = 65 GPa at room temperature and 71 GPa at 20 K. We have observed a structural transition at around 27 GPa from magnetite to a high-pressure phase h-Fe3O4 with the loss of the net ordered magnetic moments for both temperatures. The orthorhombic CaTi2O4-type (Bbmm) structure of the high-pressure phase h-Fe3O4 has been determined by combining experimental studies and theoretical simulations of the Fe K-edge X-ray absorption near-edge structure spectra. The long-time discussed pressure induced spin crossover, and inverse to normal spinel structure transitions in Fe3O4 can be deterministically excluded from the present study up to ∼65 GPa.

Published
2019

37. A Dissolution/Precipitation Equilibrium on the Surface of Iridium‐Based Perovskites Controls Their Activity as Oxygen Evolution Reaction Catalysts in Acidic Media

Author

Moulay Tahar Sougrati, Alexis Grimaud, Wei Yin, Manel Ben Osman, Ronghuan Zhang, Nicolas Dubouis, Daniel Alves Dalla Corte, Domitille Giaume, 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), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Institut de Recherche de Chimie Paris (IRCP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ministère de la Culture (MC), ANR-17-CE05-0008,MIDWAY,Contrôle des Interfaces Electrochimiques pour de meilleurs electrocatalyseurs pour l'oxydation de l'eau(2017), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ministère de la Culture (MC)

Subjects
iridium dissolution, Materials science, oxygene volution reaction, 010405 organic chemistry, Precipitation (chemistry), Inorganic chemistry, perovskites, Oxygen evolution, chemistry.chemical_element, [CHIM.CATA]Chemical Sciences/Catalysis, General Medicine, General Chemistry, Pourbaix diagram, 010402 general chemistry, Electrochemistry, 01 natural sciences, Catalysis, 0104 chemical sciences, chemistry, Pourbaix diagrams, Iridium, Deposition (chemistry), Dissolution
Abstract

International audience; Recently, Ir (V)-based perovskite-like materials were proposed as oxygen evolution reaction (OER) catalysts in acidic media with promising performance. However, iridium dissolution and surface reconstruction were observed, questioning the real active sites on the surface of these catalysts. In this work, Sr2MIr (V) O6 (M = Fe, Co) and Sr2Fe0.5Ir0.5 (V) O4 were explored as OER catalysts in acidic media. Their activities were observed to be roughly equal to that previously reported for La2LiIrO6 or Ba2PrIrO6. Coupling electrochemical measurements with iridium dissolution studies under chemical or electrochemical conditions, we show that the deposition of an IrOx layer on the surface of these perovskites is responsible for their OER activity. Furthermore, we experimentally reconstruct the iridium Pourbaix diagram which will help guide future research in controlling the dissolution/precipitation equilibrium of iridium species for the design of better Ir-based OER catalysts.

Published
2019

38. Electrochemical Evaluation of Pb, Ag, and Zn Cyanamides/Carbodiimides

Author

Moulay Tahar Sougrati, Maria Alfredsson, Richard Dronskowski, Lorenzo Stievano, Xiaohui Liu, Markus Mann, Jeethu Jiju Arayamparambil, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Advanced Lithium Energy Storage Systems - ALISTORE-ERI (ALISTORE-ERI), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Inorganic Chemistry [Aachen], Rheinisch-Westfälische Technische Hochschule Aachen (RWTH), School of Physical Sciences [Canterbury], University of Kent [Canterbury], Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institute of Inorganic Chemistry [Aachen] (IAC RWTH), Rheinisch-Westfälische Technische Hochschule Aachen University (RWTH), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), and Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)

Subjects
Diffraction, Electrode material, Materials science, General Chemical Engineering, Inorganic chemistry, 02 engineering and technology, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Electrochemistry, 01 natural sciences, 3. Good health, 0104 chemical sciences, lcsh:Chemistry, lcsh:QD1-999, ddc:660, 0210 nano-technology, Absorption (electromagnetic radiation)
Abstract

PbNCN, Ag2NCN, and ZnNCN were tested as negative\ud electrode materials for Li-ion batteries. A thorough analysis of the\ud electrochemical mechanism by X-ray diffraction and X-ray absorption\ud spectroscopy showed that, unlike transition metal carbodiimides, these\ud compounds react with lithium via a two-step reaction, starting with\ud conversion followed by alloying. The conversion reaction is highly\ud irreversible for the three compounds, whereas the reversibility of the alloying\ud reaction depends on the metal, that is, highly irreversible for PbNCN and\ud Ag2NCN which contain the cyanamide group (NC−N2−) and more\ud reversible for ZnNCN containing carbodiimide (−NCN−). In the case\ud of the more covalent, cyanamide-type PbNCN and Ag2NCN, the conversion\ud reaction occurs at a higher voltage compared to the more ionic,\ud carbodiimide-type ZnNCN, correlated with the nature of bonding in the\ud NCN group and in the phases themselves. Compared to transition metal carbodiimides, these materials show rather low\ud performance, with no improvement in capacity as it would have been expected from the combination of conversion and\ud alloying.

Published
2019

39. Hybrid iron montmorillonite nano-particles as an oxygen scavenger

Author

Nathalie Gontard, Khadijeh Khederlou, Erland-Modeste Kombaya-Touckia-Linin, Valérie Guillard, Nakry Pen, Sébastien Gaucel, Moulay Tahar Sougrati, Lorenzo Stievano, Ingénierie des Agro-polymères et Technologies Émergentes (UMR IATE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Université Montpellier 2 - Sciences et Techniques (UM2)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Institut National de la Recherche Agronomique (INRA), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Iron boride, Materials science, General Chemical Engineering, Ingénierie des aliments, Nanoparticle, 02 engineering and technology, 010402 general chemistry, nanoparticule, 01 natural sciences, Modelling, Industrial and Manufacturing Engineering, fer, Oxygen absorption kinetics, chemistry.chemical_compound, Sodium borohydride, Reaction rate constant, Mössbauer spectroscopy, Food engineering, Environmental Chemistry, Chemical synthesis, spectrométrie mossbauer, ComputingMilieux_MISCELLANEOUS, Montmorillonite, 57Fe Mössbauer spectroscopy, Zerovalent iron, Iron nanoparticles, [CHIM.MATE]Chemical Sciences/Material chemistry, General Chemistry, 021001 nanoscience & nanotechnology, cinétique d'absorption, 0104 chemical sciences, chemistry, Absorption (chemistry), 0210 nano-technology, Nuclear chemistry
Abstract

International audience; Iron nanoparticles supported on montmorillonite (MMT-Fe) were synthesized via the reduction by sodium borohydride of iron salts dissolved in a suspension of MMT. The MMT-Fe black powder collected after the evaporation of the solvent was analysed by Transmission Electron Microscopy, which revealed the formation of aggregates of metallic nanoparticles with an average size of 57 ± 17 nm dispersed on the surface of MMT. According to the X-ray diffraction, no iron ions are intercalated in the interlayer spacing of MMT, and no other crystalline species are formed. 57Fe Mössbauer spectroscopy evidences the formation of mainly zero valent iron in the form of iron boride. The O2 absorption kinetic of the synthesized powders was found to follow a second-order law. The study of the O2 absorption properties of as-synthesized, dried and stored (40 days) powders shows reaction constant (k), coefficient of proportionality (n) and O2 absorption capacities of the same order of magnitude. The O2 absorption capacity of the as-synthesized, dried and stored powders were found equal to 0.20 ± 0.01, 0.14 ± 0.03 and 0.09 ± 0.00 g O2 per g of iron, respectively. The initial absorption rate was found within the range [0.5 - 1.5] % O2 min-1 g-1.

Published
2019

40. Li- and Na-ion Storage Performance of Natural Graphite via Simple Flotation Process

Author

Noureddine Ait Laziz, John Abou-Rjeily, Ali Darwiche, Joumana Toufaily, Abdelkader Outzourhit, Fouad Ghamouss, and Moulay Tahar Sougrati

Subjects
Electrochemistry, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 0210 nano-technology, 01 natural sciences, 0104 chemical sciences
Published
2018

41. Non-Carbonaceous Negative Electrodes in Sodium Batteries

Author

Moulay Tahar Sougrati, Laure Monconduit, Lorenzo Stievano, Vincent Gabaudan, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), and Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)

Subjects
Materials science, Sodium, Inorganic chemistry, Sodium titanate, chemistry.chemical_element, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 7. Clean energy, 0104 chemical sciences, chemistry.chemical_compound, chemistry, Electrode, 0210 nano-technology, Lithium titanate
Abstract

International audience; Finding an adapted negative electrode for Na-ion batteries (NIB) is one of the critical issues for their successful development. The field of anode materials for NIB is also the one where most differences are found when compared to lithium-ion batteries. Contrary to lithium-based systems, graphite does not intercalate sodium ions with conventional electrolytes, and the alternative carbonaceous negative electrode materials that have been proposed, such as hard carbon, are characterized by relatively low specific capacities up to 300 mAh g–1 and undergo substantial irreversible capacity during the first sodiation. The materials are divided based on their reaction mechanism as insertion, alloying or conversion materials. The insertion materials include transition metal oxides, sodium titanate, lithium titanate and layered titanates. An interesting approach to obtain electrode materials from renewable resources with minimum energy consumption is using them as organic electrode materials.

Published
2021

42. Understanding how single-atom site density drives the performance and durability of PGM-free Fe–N–C cathodes in anion exchange membrane fuel cells

Author

Dario R. Dekel, Xiong Peng, Simon Brandon, Karam Yassin, Frédéric Jaouen, Noor Ul Hassan, William E. Mustain, Horie Adabi, Moulay Tahar Sougrati, Andrea Zitolo, John R. Regalbuto, Igal G. Rasin, John R. Varcoe, Pietro Giovanni Santori, Abolfazl Shakouri, University of South Carolina [Columbia], Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), University of Surrey (UNIS), European Project: 721065,CREATE, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Materials science, Oxygen reduction, 02 engineering and technology, 010402 general chemistry, 7. Clean energy, 01 natural sciences, Catalysis, law.invention, Metal, High performance, law, PGM-free, General Materials Science, Materials of engineering and construction. Mechanics of materials, Power density, Fe–N–C, Ion exchange, AEM, Mechanical Engineering, Fuel cell, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Cathode, 0104 chemical sciences, Anode, Fe-N-C, Membrane, Chemical engineering, Single-atom, visual_art, Electrode, visual_art.visual_art_medium, TA401-492, 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other
Abstract

International audience; One of the most important needs for the future of low-cost fuel cells is the development of highly active platinum group metal (PGM)-free catalysts. For the oxygen reduction reaction, Fe–N–C materials have been widely studied in both acid and alkaline media. However, reported catalysts in the literature show quite different intrinsic activity and in-cell performance, despite similar synthesis routes and precursors. Here, two types of Fe–N–C are prepared from the same precursor and procedure – the main difference is how the precursor was handled prior to use. It is shown that in one case Fe overwhelmingly existed as highly active single-metal atoms in FeN4 coordination (preferred), while in the other case large Fe particles coexisting with few single metal atoms were obtained. As a result, there were drastic differences in the catalyst structure, activity, and especially in their performance in an operating anion exchange membrane fuel cell (AEMFC). Additionally, it is shown that catalyst layers created from single-atom-dominated Fe–N–C can have excellent performance and durability in an AEMFC using H2/O2 reacting gases, achieving a peak power density of 1.8 W cm−2 – comparable to similar AEMFCs with a Pt/C cathode – and being able to operate stably for more than 100 h. Finally, the Fe–N–C cathode was paired with a low-loading PtRu/C anode electrode to create AEMFCs (on H2/O2) with a total PGM loading of only 0.135 mg cm−2 (0.090 mgPt cm−2) that was able to achieve a very high specific power of 8.4 W mgPGM−1 (12.6 W mgPt−1)

Published
2021

43. 2021 roadmap for sodium-ion batteries

Author

John T. S. Irvine, Emma Kendrick, Valerie R. Seymour, Aamod V. Desai, Edmund J. Cussen, Peter Gross, Andrew J. Naylor, Maria-Magdalena Titirici, Jake M. Brittain, Rebecca Boston, Ruth Sayers, Stewart A. M. Dickson, Sudeshna Sen, Sara I. R. Costa, Zhuangnan Li, Ashish Rudola, Heather Au, Dominic S. Wright, Nuria Tapia-Ruiz, Yongseok Choi, Hande Alptekin, John M. Griffin, Martin O. Jones, Marco Amores, Shahin Nikman, Eun Jeong Kim, A. Robert Armstrong, Reza Younesi, Maria Crespo Ribadeneyra, Laure Monconduit, William I. F. David, Christopher I Thomas, Patrik Johansson, Serena A. Cussen, Grant S. Stone, Jincheng Tong, Russell E. Morris, Clare P. Grey, Alexandre Ponrouch, Oleg Kolosov, Emmanuel I. Eweka, Darren M. C. Ould, Robert G. Palgrave, Thomas J. Wood, Yue Chen, Jerry Barker, Ronnie Mogensen, Stijn F. L. Mertens, Philippe Poizot, Juan Forero-Saboya, David O. Scanlon, Manish Chhowalla, Lorenzo Stievano, Emily M. Reynolds, Xiao Hua, Moulay Tahar Sougrati, William R. Brant, Martin Karlsmo, Stéven Renault, Christopher A. O’Keefe, Begoña Silván, Lancaster University, Harwell Science and Innovation Campus, Imperial College London, University of Sheffield [Sheffield], Faradion Limited, University of Virginia [Charlottesville], University of Oxford [Oxford], University of Cambridge [UK] (CAM), University College of London [London] (UCL), University of St Andrews [Scotland], AUTRES, Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Chalmers University of Technology [Gothenburg, Sweden], Science and Technology Facilities Council (STFC), University of Birmingham [Birmingham], Uppsala University, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN), Alistore, European Commission, Swedish Research Council, Swedish Energy Agency, Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning, Ministerio de Economía, Industria y Competitividad (España), Faraday Institution, Austrian Science Fund, Innovate UK, Tapia-Ruiz, Nuria [0000-0002-5005-7043], Armstrong, A Robert [0000-0003-1937-0936], Alptekin, Hande [0000-0001-6065-0513], Au, Heather [0000-0002-1652-2204], Barker, Jerry [0000-0002-8791-1119], Brant, William R [0000-0002-8658-8938], Choi, Yong-Seok [0000-0002-3737-2989], Costa, Sara I R [0000-0001-8105-207X], Crespo Ribadeneyra, Maria [0000-0001-6455-4430], Cussen, Serena A [0000-0002-9303-4220], Desai, Aamod V [0000-0001-7219-3428], Forero-Saboya, Juan D [0000-0002-3403-6066], Griffin, John M [0000-0002-8943-3835], Irvine, John T S [0000-0002-8394-3359], Johansson, Patrik [0000-0002-9907-117X], Karlsmo, Martin [0000-0002-0437-6860], Kendrick, Emma [0000-0002-4219-964X], Kolosov, Oleg V [0000-0003-3278-9643], Mertens, Stijn F L [0000-0002-5715-0486], Monconduit, Laure [0000-0003-3698-856X], Naylor, Andrew J [0000-0001-5641-7778], Poizot, Philippe [0000-0003-1865-4902], Renault, Stéven [0000-0002-6500-0015], Rudola, Ashish [0000-0001-9368-0698], Sayers, Ruth [0000-0003-1289-0998], Seymour, Valerie R [0000-0003-3333-5512], Silván, Begoña [0000-0002-1273-3098], Sougrati, Moulay Tahar [0000-0003-3740-2807], Stievano, Lorenzo [0000-0001-8548-0231], Thomas, Chris I [0000-0001-8090-4541], Titirici, Maria-Magdalena [0000-0003-0773-2100], Tong, Jincheng [0000-0001-7762-1460], Wood, Thomas J [0000-0002-5893-5664], Younesi, Reza [0000-0003-2538-8104], Apollo - University of Cambridge Repository, Kim, Eunjeong [0000-0002-2941-068], Kim, Eunjeong [0000-0002-2941-0682], University of Virginia, University of Oxford, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Université de Nantes (UN)-Université de Nantes (UN)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Tapia-Ruiz, N [0000-0002-5005-7043], Armstrong, AR [0000-0003-1937-0936], Alptekin, H [0000-0001-6065-0513], Au, H [0000-0002-1652-2204], Barker, J [0000-0002-8791-1119], Brant, WR [0000-0002-8658-8938], Choi, YS [0000-0002-3737-2989], Costa, SIR [0000-0001-8105-207X], Ribadeneyra, MC [0000-0001-6455-4430], Cussen, SA [0000-0002-9303-4220], Desai, AV [0000-0001-7219-3428], Forero-Saboya, JD [0000-0002-3403-6066], Griffin, JM [0000-0002-8943-3835], Irvine, JTS [0000-0002-8394-3359], Johansson, P [0000-0002-9907-117X], Karlsmo, M [0000-0002-0437-6860], Kendrick, E [0000-0002-4219-964X], Kolosov, OV [0000-0003-3278-9643], Mertens, SFL [0000-0002-5715-0486], Monconduit, L [0000-0003-3698-856X], Naylor, AJ [0000-0001-5641-7778], Poizot, P [0000-0003-1865-4902], Renault, S [0000-0002-6500-0015], Rudola, A [0000-0001-9368-0698], Sayers, R [0000-0003-1289-0998], Seymour, VR [0000-0003-3333-5512], Silván, B [0000-0002-1273-3098], Sougrati, MT [0000-0003-3740-2807], Stievano, L [0000-0001-8548-0231], Thomas, CI [0000-0001-8090-4541], Titirici, MM [0000-0003-0773-2100], Tong, J [0000-0001-7762-1460], Wood, TJ [0000-0002-5893-5664], Younesi, R [0000-0003-2538-8104], The Faraday Institution, University of St Andrews. School of Chemistry, University of St Andrews. Centre for Energy Ethics, University of St Andrews. Centre for Designer Quantum Materials, and University of St Andrews. EaSTCHEM

Subjects
Chemical process, Technology, Computer science, PAIR DISTRIBUTION FUNCTION, HIGH-ENERGY DENSITY, ELECTROCHEMICAL PROPERTIES, Materialkemi, 02 engineering and technology, 01 natural sciences, 7. Clean energy, Materials Chemistry, QD, LITHIUM-ION, Energy demand, Scope (project management), anodes, NA2TI3O7 NANOSHEETS, [CHIM.MATE]Chemical Sciences/Material chemistry, sodium ion, 021001 nanoscience & nanotechnology, Variety (cybernetics), General Energy, Roadmap, T-DAS, Lithium, 0210 nano-technology, Battery (electricity), energy materials, Energy & Fuels, HIGH-CAPACITY ANODE, batteries, Materials Science (miscellaneous), Materials Science, chemistry.chemical_element, Materials Science, Multidisciplinary, electrolytes, 010402 general chemistry, Energy storage, MECHANISTIC INSIGHTS, SDG 7 - Affordable and Clean Energy, STRUCTURAL EVOLUTION, SOLID-ELECTROLYTE INTERPHASE, Science & Technology, QD Chemistry, 0104 chemical sciences, chemistry, 13. Climate action, Sustainability, HIGH-PERFORMANCE CATHODE, Biochemical engineering, cathodes
Abstract

Tapia-Ruiz, Nuria et al., Increasing concerns regarding the sustainability of lithium sources, due to their limited availability and consequent expected price increase, have raised awareness of the importance of developing alternative energy-storage candidates that can sustain the ever-growing energy demand. Furthermore, limitations on the availability of the transition metals used in the manufacturing of cathode materials, together with questionable mining practices, are driving development towards more sustainable elements. Given the uniformly high abundance and cost-effectiveness of sodium, as well as its very suitable redox potential (close to that of lithium), sodium-ion battery technology offers tremendous potential to be a counterpart to lithium-ion batteries (LIBs) in different application scenarios, such as stationary energy storage and low-cost vehicles. This potential is reflected by the major investments that are being made by industry in a wide variety of markets and in diverse material combinations. Despite the associated advantages of being a drop-in replacement for LIBs, there are remarkable differences in the physicochemical properties between sodium and lithium that give rise to different behaviours, for example, different coordination preferences in compounds, desolvation energies, or solubility of the solid–electrolyte interphase inorganic salt components. This demands a more detailed study of the underlying physical and chemical processes occurring in sodium-ion batteries and allows great scope for groundbreaking advances in the field, from lab-scale to scale-up. This roadmap provides an extensive review by experts in academia and industry of the current state of the art in 2021 and the different research directions and strategies currently underway to improve the performance of sodium-ion batteries. The aim is to provide an opinion with respect to the current challenges and opportunities, from the fundamental properties to the practical applications of this technology., The authors gratefully acknowledge RS2E and Alistore-ERI for funding their research into Na-ion batteries. The funding received from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 646433 (NAIADES), the Swedish Research Council, the Swedish Energy Agency (#37671-1), and the Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (FORMAS), are all gratefully acknowledged. The many fruitful discussions within ALISTORE-ERI, and especially with M Rosa Palacín, have been most valuable. P J is also grateful for the continuous support from several of the Chalmers Areas of Advance: Materials Science and Energy. Funding from the European Union’s innovation program H2020 is acknowledged: H2020-MSCA-COFUND-2016 (DOC-FAM, Grant Agreement No. 754397). A Ponrouch is grateful to the Spanish Ministry for Economy, Industry and Competitiveness Severo Ochoa Programme for Centres of Excellence in R&D (SEV-2015-0496).

Published
2021

44. Porous Si/Cu6Sn5/C composite containing native oxides as anode material for lithium-ion batteries

Author

Pierre-Emmanuel Lippens, Moulay Tahar Sougrati, Zhongbin Ye, Yawen He, Mohamad Chamas, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), and Southwest Petroleum University

Subjects
Materials science, anode, porous Si composite, Composite number, chemistry.chemical_element, 02 engineering and technology, Electrolyte, Conductivity, 010402 general chemistry, 7. Clean energy, 01 natural sciences, X-ray photoelectron spectroscopy, passivation, Electrical and Electronic Engineering, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Isotropic etching, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Anode, chemistry, Chemical engineering, Lithium, 0210 nano-technology, Porous medium
Abstract

International audience; Porous Si/Cu6Sn5/C composite containing native oxides was prepared via solid state mechanical milling and wet chemical etching. This composite was used as anode material for Li-ion batteries. X-ray diffraction, electron microscopy, 119 Sn Mössbauer spectroscopy and X-ray photoelectron spectroscopy show that the composite has a pitaya-like morphology based on porous Si and embedded Cu6Sn5 nonporous microparticles with surface native oxides. Both Si and Cu6Sn5 are electrochemically active and the activation process during the first charge-discharge cycles improves the nanostructuration of the composite that helps to buffer the volume variations of the Li-Si and Li-Sn alloying reactions. The porous composite delivers a reversible and stable capacity of 900 mAh.g-1 at a galvanostatic current density of 422 mA.g-1 with a retention of 90% for 100 cycles, which is higher than porous Si (53%). The stability during cycling is explained by buffering effects, enhanced electrode conductivity and stable SEI due to the presence of native oxides and the use of FEC-containing electrolyte.

Published
2021

45. Influence of the synthesis parameters on the proton exchange membrane fuel cells performance of Fe–N–C aerogel catalysts

Author

Moulay Tahar Sougrati, Mikkel Juul Larsen, Youling Wang, Sergio Rojas, Diego Gianolio, Frédéric Jaouen, Pilar Ferrer, Sandrine Berthon-Fabry, Centre Procédés, Énergies Renouvelables, Systèmes Énergétiques (PERSEE), Mines Paris - PSL (École nationale supérieure des mines de Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), IRD Fuel Cells A/S [Denmark] (IRD), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), DIAMOND Light source, MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Materials science, Absorption spectroscopy, Energy Engineering and Power Technology, Proton exchange membrane fuel cell, 02 engineering and technology, Resorcinol, 010402 general chemistry, 01 natural sciences, Catalysis, Oxygen reduction reaction, chemistry.chemical_compound, Electrical and Electronic Engineering, Physical and Theoretical Chemistry, Rotating disk electrode, Carbon aerogel, Renewable Energy, Sustainability and the Environment, Supercritical drying, Aerogel, [CHIM.MATE]Chemical Sciences/Material chemistry, [CHIM.CATA]Chemical Sciences/Catalysis, 021001 nanoscience & nanotechnology, Acidic media, PEMFCs, 0104 chemical sciences, chemistry, Chemical engineering, Chemisorption, 0210 nano-technology, Non-precious metal catalyst
Abstract

International audience; Fe–N–C aerogel catalysts were prepared by sol–gel polycondensation of resorcinol, melamine and formaldehyde precursors in the presence of FeCl3 salt, followed by supercritical drying and thermal treatments. The effect of the mass ratio of precursors on the microstructure, iron speciation and oxygen reduction reaction (ORR) performance of the Fe–N–C aerogels was investigated by N2 sorption, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Mössbauer spectroscopy, X-ray absorption spectroscopy, CO chemisorption and rotating disk electrode in acidic medium. The best ORR performance (activity and mass transport) was obtained by an optimum balance between pore structure and active Fe-Nx species. Through acid washing, the durability of the catalyst was further improved by eliminating unstable and inactive species, particularly iron nanoparticles and iron carbide. From the CO chemisorption and turnover-frequency value, the surface sites were comparable with the highest values reported in literature. Finally, Fe–N–C aerogel catalyst was implemented a in membrane–electrode assembly with an active area of 25 cm2 and tested in single cell, emphasizing the importance of the ink formulation on the performance.

Published
2021

46. Investigating the Cycling Stability of Fe2WO6 Pseudocapacitive Electrode Materials

Author

Christophe Payen, Olivier Crosnier, Nicolas Goubard-Bretesché, Eric Quarez, Thierry Brousse, Julio César Espinosa-Angeles, Moulay Tahar Sougrati, Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC)

Subjects
Materials science, General Chemical Engineering, 02 engineering and technology, 010402 general chemistry, Electrochemistry, 01 natural sciences, Capacitance, Pseudocapacitance, law.invention, Magnetization, law, Mössbauer spectroscopy, General Materials Science, QD1-999, electrochemical capacitor, Fe2WO6, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Characterization (materials science), Capacitor, Chemistry, Chemical engineering, Transmission electron microscopy, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, [CHIM.OTHE]Chemical Sciences/Other, pseudocapacitance
Abstract

The stability upon cycling of Fe2WO6 used as a negative electrode material for electrochemical capacitors was investigated. The material was synthesized using low temperature conditions for the first time (220 °C). The electrochemical study of Fe2WO6 in a 5 M LiNO3 aqueous electrolyte led to a specific and volumetric capacitance of 38 F g−1 and 240 F cm−3 when cycled at 2 mV·s−1, respectively, associated with a minor capacitance loss after 10,000 cycles. In order to investigate this very good cycling stability, both surface and bulk characterization techniques (such as Transmission Electron Microscopy, Mössbauer spectroscopy, and magnetization measurements) were used. Only a slight disordering of the Fe3+ cations was observed in the structure, explaining the good stability of the Fe2WO6 upon cycling. This study adds another pseudocapacitive material to the short list of compounds that exhibit such a behavior up to now.

Published
2021

47. Impact of Solution Chemistry on Growth and Structural Features of Mo-substituted Spinel Iron Oxides

Author

Olaf J. Borkiewicz, Damien Dambournet, Benjamin J. Morgan, Alexander G. Squires, Lorenzo Stievano, Oleg I. Lebedev, Chérazade Haouari, Antonella Iadecola, Romain Berthelot, Moulay Tahar Sougrati, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX (PHENIX), Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Réseau sur le stockage électrochimique de l'énergie (RS2E), Université de Nantes (UN)-Aix Marseille Université (AMU)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), University of Bath [Bath], The Faraday Institution, Laboratoire de cristallographie et sciences des matériaux (CRISMAT), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-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)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Advanced Photon Source [ANL] (APS), Argonne National Laboratory [Lemont] (ANL)-University of Chicago-US Department of Energy, ANR-10-EQPX-0045,ROCK,Spectromètre EXAFS Rapide pour Cinétiques Chimiques(2010), ANR-10-LABX-0076,STORE-EX,Laboratory of excellency for electrochemical energy storage(2010), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut de Chimie du CNRS (INC), Université de Picardie Jules Verne (UPJV)-Institut de Chimie du CNRS (INC)-Aix Marseille Université (AMU)-Université de Pau et des Pays de l'Adour (UPPA)-Université de Nantes (UN)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), and Normandie Université (NU)-Institut de Chimie du CNRS (INC)

Subjects
Coordination number, Iron, Population, engineering.material, [CHIM.INOR]Chemical Sciences/Inorganic chemistry, 010402 general chemistry, 01 natural sciences, Inorganic Chemistry, Oxidation state, Physical and Theoretical Chemistry, education, education.field_of_study, Dopant, 010405 organic chemistry, Chemistry, Spinel, Precursors, 0104 chemical sciences, Crystallography, Octahedron, Metal oxide nanoparticles, engineering, Nanoparticles, Density functional theory, Absorption (chemistry), Crystallization
Abstract

International audience; The effect of crystallizing solution chemistry on the chemistry of subsequently as-grown materials was investigated for Mo-substituted iron oxides prepared by thermally activated co-precipitation. In the presence of Mo ions, we find that varying the oxidation state of the iron precursor from Fe(II) to Fe(III) causes a progressive loss of atomic long-range order with the stabilization of 2–4 nm particles for the sample prepared with Fe(III). The oxidation state of the Fe precursor also affects the distribution of Fe and Mo cations within the spinel structure. Increasing the Fe precursor oxidation state gives decreased Fe-ion occupation and increased Mo-ion occupation of tetrahedral sites, as revealed by the extended X-ray absorption fine structure. The stabilization of Mo within tetrahedral sites appears to be unexpected, considering the octahedral preferred coordination number of Mo(VI). The analysis of the atomic structure of the sample prepared with Fe(III) indicates a local ordering of vacancies and that the occupation of tetrahedral sites by Mo induces a contraction of the interatomic distances within the polyhedra as compared to Fe atoms. Moreover, the occupancy of Mo into the thermodynamic site preference of a Mo dopant in Fe2O3 assessed by density functional theory calculations points to a stronger preference for Mo substitution at octahedral sites. Hence, we suggest that the synthetized compound is thermodynamically metastable, that is, kinetically trapped. Such a state is suggested to be a consequence of the tetrahedral site occupation by Mo ions. The population of these sites, known to be reactive sites enabling particle growth, is concomitant with the stabilization of very small particles. We confirmed our hypothesis by using a blank experiment without Mo ions, further supporting the impact of tetrahedral Mo ions on the growth of iron oxide nanoparticles. Our findings provide new insights into the relationships between the Fe-chemistry of the crystallizing solution and the structural features of the as-grown Mo-substituted Fe-oxide materials.

Published
2021

49. Carbon-coated FePO4 nanoparticles as stable cathode for Na-ion batteries: A promising full cell with a Na15Pb4 anode

Author

Bidhan Pandit, Bernard Fraisse, Lorenzo Stievano, Laure Monconduit, Moulay Tahar Sougrati, Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), Université de Montpellier (UM), Réseau sur le stockage électrochimique de l'énergie (RS2E), Aix Marseille Université (AMU)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Collège de France (CdF (institution))-Université de Picardie Jules Verne (UPJV)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Pau et des Pays de l'Adour (UPPA)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Nantes Université (Nantes Univ)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM), SATT AxLR Occitanie Méditerranée (Montpellier, France), project PLOBANA (AAP Pré-Maturation 2018, 2018-003451), and ANR-10-LABX-0076,STORE-EX,Laboratory of excellency for electrochemical energy storage(2010)

Subjects
General Chemical Engineering, Electrochemistry, [CHIM.MATE]Chemical Sciences/Material chemistry
Abstract

International audience; The cheap and non-toxic FePO4, which can be recovered from spent LFP batteries, provides a reversible capacity of 103 mAh/g in coin cells, corresponding to 76% of theoretical capacity, with very good rate capability and stability. The study of the electrochemical mechanism during sodiation carried out by in situ X-ray diffraction (XRD) reveals a pure biphasic transition during Na+ (de)insertion. The chemical diffusion coefficient (DNa) determined from galvanostatic intermittent titration technique and electrochemical impedance spectroscopy varies in the range 10−16-10−10 cm2/s at room temperature depending on the degree of sodiation. As a proof of concept, a full cell fabricated using a carbon-coated C@FePO4 cathode and a Na15Pb4 anode obtained by electrochemical sodiation of recyclable Pb, maintained 76% of the initial capacity over 100 cycles at constant C/10 rate. This outstanding electrochemical performance, based on the combination of the low-cost C@FePO4 cathode with a recyclable lead-based anode, makes this new technology a promising real-world alternative for future commercial Na-ion systems.

Published
2022

50. Correlating ligand-to-metal charge transfer with voltage hysteresis in a Li-rich rock-salt compound exhibiting anionic redox

Author

Biao, Li, Moulay Tahar, Sougrati, Gwenaëlle, Rousse, Anatolii V, Morozov, Rémi, Dedryvère, Antonella, Iadecola, Anatoliy, Senyshyn, Leiting, Zhang, Artem M, Abakumov, Marie-Liesse, Doublet, and Jean-Marie, Tarascon

Abstract

Anionic redox is a double-edged sword for Li-ion cathodes because it offers a transformational increase in energy density that is also negated by several detrimental drawbacks to its practical implementation. Among them, voltage hysteresis is the most troublesome because its origin is still unclear and under debate. Herein, we tackle this issue by designing a prototypical Li-rich cation-disordered rock-salt compound Li

Published
2020

Catalog

Books, media, physical & digital resources
See catalog results