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14. X-ray diffraction and 119Sn Mossbauer spectroscopy study of a new phase in the Bi2Se3-SnSe system: SnBi4Se7

Author

Vicente, C. Perez, Tirado, J.L., Adouby, K., Jumas, J.C., Toure, A. Abba, and Kra, G.

Subjects
Inorganic compounds -- Analysis, Complex compounds -- Spectra, Chemistry
Abstract

The stoichiometric phase of the ternary system SnSe-Bi2Se3 has been synthesized. X-ray diffraction and Mossbauer spectroscopy were then used in studying its structure. Results indicate that its composition corresponds to SnBi4Se7 while the Mossbauer spectrum reveals a near perfect regular octahedral coordination of tin atoms. The unit cell is made up of three slabs with the atomic sequence Se-M-Se-M-Se-M-Se. Its structural parameters are a = 4.1602(5) angstrom units and c = 38.934(3) angstrom units.

Published
1999

16. Distribution of cations and vacancies in TaFe1.25Te3 studied by Mossbauer spectroscopy

Author

Vicente, C. Perez, Womes, M., Jumas, J.C., Sanchez, L., and Tirado, J.L.

Subjects
Ferromagnetic materials -- Analysis, Crystals -- Structure, Tellurium -- Analysis, Electronic structure -- Analysis, Chemicals, plastics and rubber industries
Abstract

The tellurium sublattice and iron clustering in the pseudo two-dimensional structure of tantalum iron telluride (TaFe1.25Te3) has been studied by 125Te and 57Fe Mossbauer spectroscopy. TaFe1.25Te3 has a rare Ta-Fe bonded network in Ta-Fe-Fe-Te ribbons with the iron atoms placed in two nonequivalent cyrstallographic sites. Results show the relative intensities of several sextet signals due to the magnetic ordering of iron atoms are associated with the partial clustering. Long-range ordering in the tellurium sublattice is governed by two different tellurium sites.

Published
1998

18. The dopant and compound forming behavior of As and Au impurities in Ga2Te3

Author

Wuyts, K., Watte, J., Langouche, G., Silverans, R.E., Zegbe, G., and Jumas, J.C.

Subjects
Semiconductors -- Impurity distribution, Gallium compounds -- Research, Semiconductor doping -- Research, Arsenic -- Analysis, Gold -- Analysis, Physics
Abstract

A combination of Mossbauer spectroscopy, x-ray diffraction, optical transmission and electrical measurements was used toanalyze the dopant and compound forming behavior of As and Au impurities in Ga2Te3. The results showed that arsenic served as an n-type dopant in Ga2Te3 and a ternary semiconductor was formed. However, there was no evidence of As n-type dopant behavior.

Published
1992

38. Synthetic versiliaite and apuanite: investigation by 57Fe Mössbauer spectroscopy

Author

Ministerio de Economía y Competitividad (España), Bayliss, R.D., Berry, F.J., Cumby, J.C., Greaves, C., Jumas, J.C., Marco, J.F., Ministerio de Economía y Competitividad (España), Bayliss, R.D., Berry, F.J., Cumby, J.C., Greaves, C., Jumas, J.C., and Marco, J.F.

Abstract

The minerals versiliaite and apuanite have been synthesised for the first time. The Fe Mössbauer spectra recorded at 298 and 4 K are reported. The results are indicative of a formulation for versiliaite as (Fe42+Fe43+)oct[Fe43+Sb123+]tetO32S2 and of apuanite as (Fe42+Fe83+)oct[Fe83+Sb163+]tetO48S4. The spectra recorded at low temperature are indicative of complex magnetic interactions. The results indicate the potential for the synthesis of further new structurally-related materials with different compositions and new low dimensional physical properties.

Published
2016

39. Technologies des énergies renouvelables : fiche de synthèse 05

Author

Flamant, Gilles, Polit, M., Robin, Jean-Jacques, Glaize, C., Jumas, J.C., Pourcelly, Gérald, Girard, Philippe, Delgenes, J.P., Laffont, T., and Boutevin, B.

Subjects
P06 - Sources d'énergie renouvelable, Stockage, énergie géothermique, Changement technologique, Énergie éolienne, Produit nouveau, Biomasse, Énergie renouvelable, Énergie solaire
Abstract

La région Languedoc-Roussillon bénéficie d'un des meilleurs gisements d'énergies renouvelables (EnR) de France, en particulier, en ce qui concerne l'énergie éolienne et l'énergie solaire. Elle est la seule région française qui développe des recherches relatives au solaire concentré et possède des installations de grande taille dans ce domaine. Un des trois pôles de compétitivité français relatifs aux EnR est basé en région (DERBI à Perpignan). Des technologies relatives aux EnR sont actuellement disponibles et matures (chaleur moyenne et basse température, photovoltaïque [PV], éolien) et devraient être développées très activement. Les points de vigilance concernent: l'acceptation des parcs éoliens, la concurrence sur l'utilisation de l'eau dans le cas du développement des agrocarburants. Les propositions d'actions sont: utiliser le pôle de compétitivité DERBI pour favoriser le développement des activités technologiques et économiques dans le domaine des EnR, promouvoir encore plus les EnR et les économies d'énergie dans l'habitat (pas seulement de l'eau chaude sanitaire), en particulier l'habitat à faible consommation et la climatisation solaire, renforcer la position unique de la région dans le domaine de la RDT sur le solaire concentré, encourager les recherches relatives au PV innovant, au stockage (électrochimique et thermique) à la production de combustibles alternatifs (hydrogène) et la gestion intelligente de l'énergie.

Published
2007

40. The BM5Se9 phases: studies of the behaviour of superconductors and ferromagnets

Author

Institut Des Matériaux Jean Rouxel, Imn, Leblanc-Soreau, A., MoliniÉ, P., Jumas, J.C., 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), Institut Charles Gerhardt Montpellier - Institut de Chimie Moléculaire et des Matériaux de Montpellier (ICGM ICMMM), and Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-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)

Subjects
Superconductivity, Mesoscopic physics, Materials science, Vanadium, chemistry.chemical_element, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, 0104 chemical sciences, Nanoclusters, Crystallography, Ferromagnetism, chemistry, Mössbauer spectroscopy, Singlet state, 0210 nano-technology, Spectroscopy
Abstract

Syntheses performed in the A 3 B/MSe 2 systems lead to the formation of (B/B')(M/A) 5 Se 9 phases (ferromagnets or superconductors) {A=M= (Nb, V, Ta); B=B'= (Al, Ge, Ga, Sn, Sb)}. The magnetic studies on GaV 5 Se 9 , GaV 0.15 Ta 4.85 Se 9 and Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 , compared to that of SnNb 5 Se 9 , GaNb 5 Se 9 show that the presence of V modifies the superconducting exchanges and allows ferromagnetic couplings. Through Point-Contact Spectroscopy on SnNb 5 Se 9 , it is shown that nanoclusters of the pristine NbSe 2 and Nb 3 Sn exist, so the properties result from a synergy between them and the matrix, and it could be a mesoscopic superconductor. The superconductors' s T c values vary from 17.5(2) K for SnNb 5 Se 9 to 6.0(2) K for SbNb 5 Se 9 , and the ferromagnetic state transition from 22K for GaV 5 Se 9 , to 35 K for Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 . The 119 Sn and 121 Sb Mossbauer studies of Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 and SbNb 5 Se 9 are compared to that obtained for SnNb 5 Se 9 itself; for this last one, 3 types of sites corresponding to 2 species of Sn were observed with a reversible dynamic process between the 2 SnII Sn-Se sites correlated to a modification of the Sn-Nb site(1). SbNb 5 Se 9 , at 5 K, shows just a singlet, attributed to Sb surrounded by Se ; from 298 K to 5 K, Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 , presents one asymmetrical Sn-Se site without any transferred field on Sn and an increased asymmetry when T decreases. Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 is a weak and complicated ferromagnet. In both cases, GaV 5 Se 9 , and Sn 0.94 Ga 0.05 V 0.30 Nb 4.70 Se 9 , the ESR spectrum observed at 300 K can be fitted with 2 lorentzian distributions: for the first case, with axial symmetries, for the second only one remains with an axial symmetry, belonging to the V sites. its vanadium sites are thus less symmetrical than in the first case.

Published
2006
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41. Couplages entre processus microbiens et réactivité géochimique abiotique dans le sol: application à l'étude de l'apparition et du devenir de pollutions affectées par des périodes transitoires d'anoxie

Author

Renault, Pierre, Dassonville, Fabrice, Pautremat, Nathalie, Cazevieille, Patrick, Marlet, Serge, Godon, Jean-Jacques, Cambier, Philippe, Richaume, Agnès, Jumas, J.C., Debroux, Laurent, Domeizel, Marianne, Environnement Méditerranéen et Modélisation des Agro-Hydrosystèmes (EMMAH), Avignon Université (AU)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Laboratoire de Biotechnologie de l'Environnement [Narbonne] (LBE), Institut National de la Recherche Agronomique (INRA)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Unité de recherche Science du Sol (USS), Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ecologie Microbienne - UMR 5557 (LEM), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Ecole Nationale Vétérinaire de Lyon (ENVL)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Agrégats Moléculaires et Matériaux Inorganiques (LAMMI), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS), Université de Provence - Aix-Marseille 1, ProdInra, Migration, 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)-Institut National de la Recherche Agronomique (INRA), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Ecole Nationale Vétérinaire de Lyon (ENVL), and Centre National de la Recherche Scientifique (CNRS)-Université Montpellier 2 - Sciences et Techniques (UM2)

Subjects
P33 - Chimie et physique du sol, [SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, GEOCHIMIE, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, P02 - Pollution, ComputingMilieux_MISCELLANEOUS
Abstract

* INRA Centre d'Avignon, Documentation, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9 Diffusion du document : INRA Centre d'Avignon, Documentation, Domaine St Paul, Site Agroparc, 84914 Avignon cedex 9; National audience

Published
2005

43. Role of iron oxides in the phosphate adsorption properties of kaolinites from the ivory coast

Author

Sei, Joseph, Jumas, J.C., Olivier-Fourcade, J., Quiquampoix, Herve, Staunton, Siobhan, ProdInra, Migration, Unité de Science du Sol, and Institut National de la Recherche Agronomique (INRA)

Subjects
[SDV] Life Sciences [q-bio], [SDE] Environmental Sciences, [SDV]Life Sciences [q-bio], [SDE]Environmental Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2002

44. Influence of sulfur vacancies on the electronic properties of In16Sn4S32

Author

Dedrivere, D., Lippens, P.E., Jumas, J.C., Lefebvre-Devos, I., Perez-Vicente, C., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2001

45. Bonding in skutterudites : combined experimental and theoretical characterization of CoSb3

Author

Lefebvre-Devos, I., Lassalle, M., Wallart, X., Olivier-Fourcade, J., Monconduit, L., Jumas, J.C., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire des Agrégats Moléculaires et Matériaux Inorganiques (LAMMI), and Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI]Engineering Sciences [physics]
Abstract

We report on the bonding in skutterudites using the CoSb3 example. The theoretical electronic structure is calculated in both density-functional theory and empirical tight-binding frameworks. It is shown to be in good agreement with x-ray photoemission and photoabsorption experiments, and with Sb Mössbauer spectroscopy. It is then used to demonstrate that (i) the Sb4 rings are not the main structural features to analyze the highest valence-band behavior, (ii) the structure must be described in terms of comer-connected CoSb6 octahedra, which are tilted to form the Sb rings.

Published
2001
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46. Preparation and characterization of a stable FeSO4F-based framework for alkali ion insertion electrodes

Author

Recham, N., Rousse, G., Sougrati, M.T., Chotard, J.N., Frayret, C., Mariyappan, S., Melot, B.C., Jumas, J.C., Tarascon, J.M., Recham, N., Rousse, G., Sougrati, M.T., Chotard, J.N., Frayret, C., Mariyappan, S., Melot, B.C., Jumas, J.C., and Tarascon, J.M.

Abstract

Polyanionic electrode materials offer an attractive combination of safety benefits and tunable redox potentials. Thus far, phosphate-based phases have drawn the most interest with a subsequent surge of activity focused on the newly discovered family of fluorosulfate phases. Here, we report the preparation of a new potassium-based fluorosulfate, KFeSO4F, which, with removal of K, leads to a new polymorph of FeSO4F crystallizing in the high-temperature structure of KTiOPO4. This new phase which contains large, empty channels, is capable of reversibly inserting 0.9 Li+ per unit formula and can accommodate a wide variety of alkali ions including Li+, Na+, or K+. This finding not only expands the rich crystal chemistry of the fluorosulfate family but further suggests that a similar strategy can apply to other K-based polyanionic compounds in view of stabilizing new attractive host structures for insertion reactions. © 2012 American Chemical Society.

Published
2012

47. Single-step synthesis of FeSO 4F 1-yOH y (0 ≤y ≤1) positive electrodes for li-based batteries

Author

Ati, M., Sougrati, M.T., Rousse, G., Recham, N., Doublet, M.L., Jumas, J.C., Tarascon, J.M., Ati, M., Sougrati, M.T., Rousse, G., Recham, N., Doublet, M.L., Jumas, J.C., and Tarascon, J.M.

Abstract

The recent discovery of electrochemical activity at 3.6 V vs Li +/Li 0 in LiFeSO 4F has generated widespread research activity in this new family of fluorosulfate electrode materials aiming at either increasing the Fe 3+/Fe 2+ redox potential, searching for new active members, or extending this family to hydroxyl-fluorosulfates. Here we present a new low temperature single step synthesis of FeSO 4F 1-yOH y phases using FeF 3 and Fe 2(SO 4) 3•nH 2O as precursors. Using thorough chemical analytical techniques to test for F - content in conjunction with Mössbauer measurements, we demonstrate the existence of a limited solid solution (0.35 < y<1) within this system. Members pertaining to this solid solution have a redox activity ranging from 3.2 to 3.6 V vs Li +/Li 0 and show sustained reversible capacity retention of 130 mAh/g which makes them potentially interesting for Li-based polymer batteries. We demonstrate that the Li-insertion-deinsertion mechanism depends markedly on the sample F -content by using joint in situ XRD and Mössbauer spectroscopy. Moreover, we show the versatility of our synthetic approach by extending it to the elaboration of Fe 1-zM zSO 4F 1-yOH y phases with M = Ti and V. © 2012 American Chemical Society.

Published
2012

48. Lithium insertion in SnS2

Author

Lefebvre, I., Olivier-Fourcade, J., Jumas, J.C., Lavela, P., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2000

49. A 3.90 v iron-based fluorosulphate material for lithium-ion batteries crystallizing in the triplite structure

Author

Barpanda, P., Ati, M., Melot, B.C., Rousse, G., Chotard, J.N., Doublet, M.L., Sougrati, M.T., Corr, S.A., Jumas, J.C., Tarascon, J.M., Barpanda, P., Ati, M., Melot, B.C., Rousse, G., Chotard, J.N., Doublet, M.L., Sougrati, M.T., Corr, S.A., Jumas, J.C., and Tarascon, J.M.

Abstract

Li-ion batteries have empowered consumer electronics and are now seen as the best choice to propel forward the development of eco-friendly (hybrid) electric vehicles. To enhance the energy density, an intensive search has been made for new polyanionic compounds that have a higher potential for the Fe 2+/Fe 3+ redox couple. Herein we push this potential to 3.90 V in a new polyanionic material that crystallizes in the triplite structure by substituting as little as 5 atomic per cent of Mn for Fe in Li(Fe 1-δ Mn δ)SO 4 F. Not only is this the highest voltage reported so far for the Fe 2+/Fe 3+ redox couple, exceeding that of LiFePO 4 by 450 mV, but this new triplite phase is capable of reversibly releasing and reinserting 0.7-0.8 Li ions with a volume change of 0.6% (compared with 7 and 10% for LiFePO 4 and LiFeSO 4F respectively), to give a capacity of ∼125 mA h g -1. © 2011 Macmillan Publishers Limited. All rights reserved.

Published
2011

50. Synthesis of new fluorosulphate materials using different approaches

Author

Ati, M., Sougrati, M.T., Recham, N., Barpanda, P., Reynaud, M., Delacourt, C., Armand, M., Jumas, J.C., Tarascon, J.M., Ati, M., Sougrati, M.T., Recham, N., Barpanda, P., Reynaud, M., Delacourt, C., Armand, M., Jumas, J.C., and Tarascon, J.M.

Abstract

Searching for possible new cathode materials with the ability to outperform LiFePO 4, our group has recently discovered LiFeSO 4F, a novel metal fluorosulphate compound. Needing no further optimization, it delivers excellent reversible capacity (∼140 mAh/g) involving a 3.6 V Fe II/III redox plateau. This parent fluorosulphate phase has been synthesized by three different routes; namely ionothermal synthesis, solid-state synthesis and polyol-assisted synthesis. These low temperature synthesis routes are described focusing on synthesis of LiFeSO 4F. Furthermore, these methods were successfully employed to unravel other LiMSO 4F compounds (M =Co/Ni/Mn/Zn) as well as sodium-based metal fluorosulphate NaMSO 4F compounds (M = Fe/Co/Ni/Mn). These syntheses were realized at temperature not exceeding 300°C. We have discovered many interesting and at times intriguing structural, electrochemical and transport properties in these fluorosulphate materials. A few of these findings are illustrated to show the richness of the metal fluorosulphate chemistry. ©The Electrochemical Society.

Published
2011

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