Exploring the electrochemical behavior of InSb as negative electrode for Mg-ion batteries

International audienceMagnesium metal has a tendency to react with conventional electrolytes to form a barrier on its surface[1], rendering cations exchange impossible, and thus dramatically limiting reversible stripping/deposition of Mg. Unlike Mg metal, alloys based on p-block elements (Sn, Sb, In, Pb, Bi) do not appear to suffer from the formation of a blocking passivation layer in conventional electrolytes. These substitute electrodes appear therefore as a promising solution to overcome the problem of compatibility with electrolytes, even if the reaction mechanisms behind their operation in conventional electrolytes are still unsolved. In order to improve the performance of these electrodes, we evaluated a possible synergy effect between p-block elements, as already shown for SnSb[2] and BiSb[3]. We chose to work on InSb that may combine the high theoretical capacity of Sb and the lowest working potential reported for In. InSb, synthetized by ball-milling, shows an electrochemical behavior (Figure 1) drastically different from those of the lone elements. We will demonstrate that the combination of In and Sb is beneficial as it promotes the reactivity of Sb, similarly to BiSb alloy[3]. Structural and morphological ex situ characterization will also be described in details and correlated with the peculiar electrochemical behavior of InSb. Figure 1: Voltage profile of an InSb-based electrode cycled at a rate of C/100 in an electrolyte based of EtMgCl and Et2AlCl in THF

Pharmacogenomics of the efficacy and safety of Colchicine in COLCOT

© 2021 The Authors. Circulation: Genomic and Precision Medicine is published on behalf of the American Heart Association, Inc., by Wolters Kluwer Health, Inc. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial License, which permits use, distribution, and reproduction in any medium, provided that the original work is properly cited and is not used for commercial purposes.Background: The randomized, placebo-controlled COLCOT (Colchicine Cardiovascular Outcomes Trial) has shown the benefits of colchicine 0.5 mg daily to lower the rate of ischemic cardiovascular events in patients with a recent myocardial infarction. Here, we conducted a post hoc pharmacogenomic study of COLCOT with the aim to identify genetic predictors of the efficacy and safety of treatment with colchicine. Methods: There were 1522 participants of European ancestry from the COLCOT trial available for the pharmacogenomic study of COLCOT trial. The pharmacogenomic study's primary cardiovascular end point was defined as for the main trial, as time to first occurrence of cardiovascular death, resuscitated cardiac arrest, myocardial infarction, stroke, or urgent hospitalization for angina requiring coronary revascularization. The safety end point was time to the first report of gastrointestinal events. Patients' DNA was genotyped using the Illumina Global Screening array followed by imputation. We performed a genome-wide association study in colchicine-treated patients. Results: None of the genetic variants passed the genome-wide association study significance threshold for the primary cardiovascular end point conducted in 702 patients in the colchicine arm who were compliant to medication. The genome-wide association study for gastrointestinal events was conducted in all 767 patients in the colchicine arm and found 2 significant association signals, one with lead variant rs6916345 (hazard ratio, 1.89 [95% CI, 1.52-2.35], P=7.41×10-9) in a locus which colocalizes with Crohn disease, and one with lead variant rs74795203 (hazard ratio, 2.51 [95% CI, 1.82-3.47]; P=2.70×10-8), an intronic variant in gene SEPHS1. The interaction terms between the genetic variants and treatment with colchicine versus placebo were significant. Conclusions: We found 2 genomic regions associated with gastrointestinal events in patients treated with colchicine. Those findings will benefit from replication to confirm that some patients may have genetic predispositions to lower tolerability of treatment with colchicine.info:eu-repo/semantics/publishedVersio

Phase transformations and electrochemical behavior of InSb and In-Pb negative electrodes for Mg-ion batteries

L’accélération continuelle de la demande en lithium, combinée à son abondance limitée et sa concentration inhomogène dans la croûte terrestre risque d’augmenter considérablement son prix dans un futur proche. Les batteries au Mg sont une alternative prometteuse aux batteries Li-ion du fait de la grande abondance, du coût et des capacités du Mg. Néanmoins le Mg métal réagit avec les électrolytes conventionnels pour former une couche de passivation à sa surface rendant l’échange de cations impossible. Une alternative intéressante réside dans le remplacement du Mg métal par une électrode négative hôte, surmontant le problème de compatibilité avec les électrolytes. L’objectif de ce travail est d’étudier le comportement électrochimique et les mécanismes de réactions de deux alliages d’éléments du bloc p en tant qu’électrode négative de batteries Mg : In-Pb:C et InSb, synthétisés par broyage.Une forte synergie entre In et Sb est mise en évidence dans InSb avec la promotion de l'activité électrochimique du Sb avec Mg, impossible dans le cas de Sb seul. Cet effet synergique n’est présent qu’au premier cycle électrochimique pour In-Pb:C. En couplant des caractérisations DRX ex situ et operando et XAS, nous avons suivi les transformations de phases durant les processus de (dé)magnésiation. En particulier, une amorphisation de la phase MgIn est induite par la première magnésiation de InSb et In-Pb:C. Afin d’améliorer les performances de InSb, la morphologie des poudres a été modifiée via une synthèse par réduction. Bien que les performances soient peu améliorées, la cristallisation de la phase MgIn est favorisée quand les particules sont nanostructurées. Ce comportement suggère une compétition entre cristallisation et amorphisation dépendante de la morphologie.The perpetual acceleration of the lithium demand combined with its relatively low abundance and uneven concentration on the Earth’s crust might dramatically increase its price in a near future. Mg batteries are a promising alternative to Li-ion batteries thanks to Mg high abundance, low cost and capacity. Yet, metallic Mg reacts with conventional electrolytes to form a barrier on its surface, preventing cation exchange. An interesting alternative is to replace Mg metal with a host negative electrode, overcoming the electrolyte compatibility problem. The objective of this work is to study the electrochemical behaviour and reaction mechanisms of two p-block elements alloys used as a negative electrode in Mg-ion systems: In-Pb:C and InSb made by ball-milling.A strong synergy between In and Sb is evidenced in InSb with the electrochemical activation of Sb with Mg, inactive as a pure element. This synergetic effect is only present on the first magnesiation for In-Pb:C. By coupling operando and ex situ XRD with XAS, we followed the phase transformations during (de)magnesiation. Especially, an amorphization of MgIn is induced by the first magnesiation of InSb and In-Pb:C. To improve the performance of InSb, the morphology of the powder was modified via a reduction synthesis. Although performances are slightly improved, the crystallization of the MgIn phase is favored for nanostructured particles. This behavior suggests a competition between crystallization and amorphization depending of the material’s morphology

Transformations de phases et comportement électrochimique d’électrodes négatives à base d’InSb et d’In-Pb pour les batteries Mg-ion

The perpetual acceleration of the lithium demand combined with its relatively low abundance and uneven concentration on the Earth’s crust might dramatically increase its price in a near future. Mg batteries are a promising alternative to Li-ion batteries thanks to Mg high abundance, low cost and capacity. Yet, metallic Mg reacts with conventional electrolytes to form a barrier on its surface, preventing cation exchange. An interesting alternative is to replace Mg metal with a host negative electrode, overcoming the electrolyte compatibility problem. The objective of this work is to study the electrochemical behaviour and reaction mechanisms of two p-block elements alloys used as a negative electrode in Mg-ion systems: In-Pb:C and InSb made by ball-milling.A strong synergy between In and Sb is evidenced in InSb with the electrochemical activation of Sb with Mg, inactive as a pure element. This synergetic effect is only present on the first magnesiation for In-Pb:C. By coupling operando and ex situ XRD with XAS, we followed the phase transformations during (de)magnesiation. Especially, an amorphization of MgIn is induced by the first magnesiation of InSb and In-Pb:C. To improve the performance of InSb, the morphology of the powder was modified via a reduction synthesis. Although performances are slightly improved, the crystallization of the MgIn phase is favored for nanostructured particles. This behavior suggests a competition between crystallization and amorphization depending of the material’s morphology.L’accélération continuelle de la demande en lithium, combinée à son abondance limitée et sa concentration inhomogène dans la croûte terrestre risque d’augmenter considérablement son prix dans un futur proche. Les batteries au Mg sont une alternative prometteuse aux batteries Li-ion du fait de la grande abondance, du coût et des capacités du Mg. Néanmoins le Mg métal réagit avec les électrolytes conventionnels pour former une couche de passivation à sa surface rendant l’échange de cations impossible. Une alternative intéressante réside dans le remplacement du Mg métal par une électrode négative hôte, surmontant le problème de compatibilité avec les électrolytes. L’objectif de ce travail est d’étudier le comportement électrochimique et les mécanismes de réactions de deux alliages d’éléments du bloc p en tant qu’électrode négative de batteries Mg : In-Pb:C et InSb, synthétisés par broyage.Une forte synergie entre In et Sb est mise en évidence dans InSb avec la promotion de l'activité électrochimique du Sb avec Mg, impossible dans le cas de Sb seul. Cet effet synergique n’est présent qu’au premier cycle électrochimique pour In-Pb:C. En couplant des caractérisations DRX ex situ et operando et XAS, nous avons suivi les transformations de phases durant les processus de (dé)magnésiation. En particulier, une amorphisation de la phase MgIn est induite par la première magnésiation de InSb et In-Pb:C. Afin d’améliorer les performances de InSb, la morphologie des poudres a été modifiée via une synthèse par réduction. Bien que les performances soient peu améliorées, la cristallisation de la phase MgIn est favorisée quand les particules sont nanostructurées. Ce comportement suggère une compétition entre cristallisation et amorphisation dépendante de la morphologie

Exploration d’alliages comme électrodes négatives de batteries Mg-ion

International audienc

Variation in the use of discourse markers in a language contact situation

Use of discourse markers by 17 speakers of Anglophone Montreal French (AMF) showed great variation in individual repertoires and frequency of use. Only five subjects manifested rates of usage comparable to those native speakers or to their own L1 usage in English. In decreasing order of frequency, the speakers used tu sais 'y'know'; la 'there' (the most frequent among L1 Montreal French speakers); bon 'good', alors 'so', comme 'like', and bien 'well'; and the local discourse conjunction fait que 'so'. The subjects occasionally made use of the English markers you know, so, like, and well. Quebecois French markers with no English equivalent were used by the speakers who had been exposed to French in their early childhood environment. The one marker that showed influence from English was comme, apparently calqued on English like. Overall, frequent use of discourse markers correlated only with the speakers' knowledge of French grammar—evidence that a higher frequency of discourse marker use is the hallmark of the fluent speaker. As a feature that is not explicitly taught in school, mastery of the appropriate use of discourse markers is thus particularly revealing of the speakers' integration into the local speech community

Unexpected behavior of InSb alloy for Mg-Ion batteries: unlocking the reversibility of Sb

International audienceElectrochemical behavior and performance of negative electrodes in metal batteries can be modified and improved by combining different elements. Herein, a beneficial coupling of In and Sb in the alloying reaction with Mg was considered through the preparation of the InSb alloy by mechanochemical synthesis. Despite a strong inactivity of Sb as a sole element in Mg-ion batteries, the combination of Sb with In partially unlocks the reversibility of the alloying reaction of Sb with Mg to form Mg3Sb2. For the first time, this beneficial effect is not only observed during the first magnesiation but along few tens of cycles. The analysis of the behavior of InSb through electrochemical and X-ray diffraction measurements also revealed a more complex path than reported in the literature. Uncommonly a preferential electrochemically-driven amorphization of MgIn is suggested in standard galvanostatic measurements. Crystallization of MgIn is however observed through a galvanostatic intermittent titration technique, suggesting strong kinetic effects on the microstructure, strain or disorder in the InSb phase upon magnesiation

Influence of electrolyte on the electrode/electrolyte interface formation on InSb electrode in Mg-Ion batteries

International audienceAchieving the full potential of magnesium-ion batteries (MIBs) is still a challenge due to the lack of adequate electrodes or electrolytes. Grignard-based electrolytes show excellent Mg plating/stripping, but their incompatibility with oxide cathodes restricts their use. Conventional electrolytes like bis(trifluoromethanesulfonyl)imide ((Mg(TFSI)$_2$) solutions are incompatible with Mg metal, which hinders their application in high-energy Mg batteries. In this regard, alloys can be game changers. The insertion/extraction of Mg$^{2+}$ in alloys is possible in conventional electrolytes, suggesting the absence of a passivation layer or the formation of a conductive surface layer. Yet, the role and influence of this layer on the alloys performance have been studied only scarcely. To evaluate the reactivity of alloys, we studied InSb as a model material. Ex situ X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy were used to investigate the surface behavior of InSb in both Grignard and conventional Mg(TFSI)$_2$/DME electrolytes. For the Grignard electrolyte, we discovered an intrinsic instability of both solvent and salt against InSb. XPS showed the formation of a thick surface layer consisting of hydrocarbon species and degradation products from the solvent (THF) and salt (C$_2$H$_5$MgCl−(C$_2$H$_5$)$_2$AlCl). On the contrary, this study highlighted the stability of InSb in Mg(TFSI)$_2$ electrolyte

Electrochemical reactivity of In-Pb solid solution as a negative electrode for rechargeable Mg-ion batteries

International audienceA composite In-Pb:carbon was successfully synthetized by a two-step mechanochemical synthesis in order to obtain an adequate particles size and structure to investigate the electrochemical reactivity of the In-Pb solid solution towards Mg. A potential synergetic coupling of electroactive elements In and Pb was examined using electrochemical and ex situ X-ray diffraction analyses. The potential profile of the solid solution indicates the formation of Mg2Pb and MgIn. However, the diffraction study suggests a peculiar electrochemically-driven amorphization of MgIn during the magnesiation, in strong contrast to MgIn crystallization in In-based and InBi-based electrodes reported in the literature. Combining In and Pb favors the amorphization of MgIn and a high first magnesiation capacity of about 550 mAh g−1, but is thereafter detrimental to the material’s reversibility. These results emphasize the possible influence of electrochemically-driven amorphization and crystallization processes on electrochemical performance of battery materials