456 research outputs found
A village on the outskirts of the Ottoman empire: archaeological research at Tell Zeyd
No full textThis paper presents the most recent results from the research programme Zeyd Archaeological Project; launched in 2022, this project aims at exploring economy and society in the hinterland of the historical province of Mosul in the long Islamic period focusing on a highly representative site of the area, Tell Zeyd. Three seasons of archaeological research at the site have made it possible to put together a rich assemblage of data that illustrates settlement patterns and production at the village in the Ottoman period. This paper focuses on the evidence that emerged from the 2024 excavations, and, more specifically, on the occupation phases that can be ascribed to
the Early Ottoman period (Period E), datable to around the sixteenth century
Development of advanced silicon anode material for Li-ion and K-ion batteries
No full textRechargeable Li-ion technology is considered as the battery of choice for electric vehicles and large-scale smart grids thanks to its unrivaled electrochemical properties (1). However, important amelioration in battery performance are still required, particularly in terms of energy density, power delivery capabilities and cycle life. The search for new highly efficient electrode materials for energy storage is an ongoing challenge for both basic and industrial applications (2-4). Silicon (Si) with high theoretical capacity of 4200 mAh.g-1 is one of the most promising LIB anodes and a potential candidate to replace commercial graphite for applications such as EVs. To ensure implementation of silicon in practical applications, the cyclic performance of Si needs crucial improvements. Indeed, silicon particles demonstrate large volume expansion in subsequent cycles that causes the capacity fading due to electrode pulverization (5). This drawback can be avoided through the formation of Silicon/carbon composites in which the size of the silicon particles and their dispersion is well controlled.
In this work, the silicon-carbon composite particles in which silicon particles are intermixed with the conductive carbon network are prepared by spray drying as shaping method followed by a thermal treatment step under controller atmosphere (2, 6). The obtained composite demonstrates hollow spherical structure capable of withstanding and accommodate the expansion/shrinkage of Si upon lithiation/delithiation. The obtained Si/C anode material delivers a specific capacity of 1200 mAh.g-1, with capacity retention of 100% over long cycling performance of 1500 cycles which is more reliable as compared to other reported electrodes in the literature (6). We also show the primary results of the Si/C anode material for K-ion batteries (6).
References
1. A. Mahmoud, I. Saadoune, P.-E. Lippens, M. Chamas, R. Hakkou, J.M. Amarilla, Solid State Ionics, 300 (2017), pp. 175-181. https://doi.org/10.1016/j.ssi.2016.12.012.
2. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076. https://doi.org/10.3390/ma11071076.
3. C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Electrochimica Acta 250 (2017) 49–58. https://doi.org/10.1016/j.electacta.2017.08.006
4. C. Karegeya, A. Mahmoud, F. Hatert, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. J. Power Sources 388 (2018) 57-64. https://doi.org/10.1016/j.jpowsour.2018.03.069
5. N. Eshraghi, L. Berardo, A. Schrijnemakers, V. Delaval, M. Shaibani, M. Majumder, R. Cloots, B. Vertruyen, F. Boschini and A. Mahmoud, ACS Sustain. Chem. Eng., 8, 15 (2020) 5868–5879. https://doi.org/10.1021/acssuschemeng.9b07434
6. N. Eshraghi, A. Mahmoud, F. Boschini, R. Cloots, EP Patent EP3654413 (2020).
ACKNOWLEDGMENTS
The authors are grateful to the University of Liège and FRS-FNRS for the financial support. Part of this work was supported by the Walloon Region under the “PE PlanMarshall2. vert”program (BATWAL 1318146). A.M. is grateful to the Walloon region for a Beware Fellowship Academia 2015-1,RESIBAT no. 1510399 and University of Liége
Spray dryer as versatile synthesis method for phosphate based polyanionics cathodes materials for Na-ion or K-ion batteries
No full textLe spray drying comme méthode de synthèse versatile des matériaux de cathodes polyanioniques à base de phosphate pour batteries Na-ion et K-ion.
Jérôme Bodart a*, Nicolas Eshraghi b, Bénédicte Vertuyen a, Frédéric Boschini a et Abdelfattah Mahmoud a
a GREEnMat Groupe de Recherche en Énergie et Environnement par les Matériaux , Université de Liège, allée du six Aout, 13, 4000 Liège Belgique
b Center for Low-Emission Transport, Battery Technologies, AIT Austrian Institute of Technology, Giefinggasse 2, 1210, Vienna (Austria)
* [email protected]
Dans le contexte des technologies de stockage d'énergie, développer de nouveaux matériaux à haute performance, à longue durée de vie tout en étant respectueux de l'environnement et abordables est devenu un défi majeur de notre époque. Pour réussir à relever ce défi, il est essentiel de trouver des méthodes efficaces d'optimisation des matériaux d'électrodes des batteries rechargeables. En effet, il a été démontré que la pureté des matériaux, la composition, la taille des particules, la cristallinité, l'agrégation et la porosité des particules sont des caractéristiques qui déterminent les performances électrochimiques des matériaux de la batterie. De plus, l'optimisation de la microstructure est un paramètre clé pour obtenir des matériaux performants. Ces paramètres sont liés aux méthodes et aux paramètres de synthèse permettant d’obtenir le matériau d'électrode. Par conséquent, il est essentiel de trouver une méthode de synthèse appropriée et d’optimiser les conditions de synthèse pour préparer le matériau d'électrode actif.
Le séchage par atomisation est une méthode simple qui permet contrôler les propriétés morphologiques des matériaux d'électrode. En plus de sa polyvalence, la méthode de séchage par atomisation présente les avantages d'être rentable, facilement évolutive et permet d'obtenir des poudres composites très homogènes 1. Cela en fait une méthode de choix pour préparer des poudres complexes (multi-composants) caractérisées par une grande homogénéité, et par de très bonnes propriétés électrochimiques.
La méthode de séchage par atomisation a été utilisée dans ce travail pour synthétiser différents composés polyanioniques comme matériaux actifs de cathodes pour les batteries Na/K-ion (tels que Na2FePO4F , K3Fe2(PO4)3 et K3V(PO4)2 ) et aussi pour améliorer leur conductivité électronique par addition de sources de carbone 2–5. La méthode de séchage par atomisation permet de faciliter la synthèse de matériaux polyanioniques en assurant une très bonne homogénéité des ions à l’échelle de la gouttelette. Cette méthode permet également la réalisation rapide et facile de composite avec différentes sources de carbone tels que les nanotubes de carbones ou l’oxyde de graphène. L'influence de la méthode de synthèse et de l'ajout de sources de carbone sur les propriétés structurales, morphologiques et électrochimiques des matériaux d'électrode a été rigoureusement analysée en combinant différentes techniques de caractérisation telles que : XRD, SEM et TEM, spectroscopie Mössbauer (pour les matériaux contenant du fer) , BET, Voltammétrie Cyclique, Cyclage Galvanostatique etc.
(1) Vertruyen, B.; Eshraghi, N.; Piffet, C.; Bodart, J.; Mahmoud, A.; Boschini, F. Spray-Drying of Electrode Materials for Lithium- and Sodium-Ion Batteries. Materials (Basel). 2018, 11 (7), 1076. https://doi.org/10.3390/ma11071076.
(2) Brisbois, M.; Krins, N.; Hermann, R. P.; Schrijnemakers, A.; Cloots, R.; Vertruyen, B.; Boschini, F. Spray-Drying Synthesis of Na2FePO4F/Carbon Powders for Lithium-Ion Batteries. Mater. Lett. 2014, 130, 263–266. https://doi.org/10.1016/j.matlet.2014.05.121.
(3) Mahmoud, A.; Caes, S.; Brisbois, M.; Hermann, R. P.; Berardo, L.; Schrijnemakers, A.; Malherbe, C.; Eppe, G.; Cloots, R.; Vertruyen, B.; Boschini, F. Spray-Drying as a Tool to Disperse Conductive Carbon inside Na2FePO4F Particles by Addition of Carbon Black or Carbon Nanotubes to the Precursor Solution. J. Solid State Electrochem. 2018, 22 (1), 103–112. https://doi.org/10.1007/s10008-017-3717-x.
(4) Brisbois, M.; Caes, S.; Sougrati, M. T.; Vertruyen, B.; Schrijnemakers, A.; Cloots, R.; Eshraghi, N.; Hermann, R. P.; Mahmoud, A.; Boschini, F. Na2FePO4F/Multi-Walled Carbon Nanotubes for Lithium-Ion Batteries: Operando Mössbauer Study of Spray-Dried Composites. Sol. Energy Mater. Sol. Cells 2016, 148, 67–72. https://doi.org/10.1016/j.solmat.2015.09.005.
(5) Bodart, J.; Eshraghi, N.; Carabin, T.; Vertruyen, B.; Cloots, R.; Boschini, F.; Mahmoud, A. Spray-Dried K3V(PO4)2/C Composites as Novel Cathode Materials for K-Ion Batteries with Superior Electrochemical Performance. J. Power Sources 2020, 480 (June). https://doi.org/10.1016/j.jpowsour.2020.229057
Spray Drying of Phosphate based Cathode Materials for Na-ion and K-ion Batteries with Advanced Electrochemical Performance
No full textBatteries have become an essential and primordial solution in tackling energy security and global warming. Rechargeable Li-ion technology (LIBs), by having the highest energy density of any such device, is considered as the battery of choice for electric vehicles and large-scale smart grids. However, LIBs cannot fulfill all urgent and future needs to realize mobiles and large-scale applications. Due to the high abundance of sodium and potassium, Na-ion batteries (NIBs) and K-ion batteries (KIBs) have recently emerged as highly interesting candidates. Despite advances in the development of cathode materials for NIBs and KIBs during the last few years, there is still much room for improvement. Indeed, the main challenge in KIBs and NIBs concerns the development of suitable cathode materials with high capacity, high voltage, long cycle life and low cost to boost energy density to levels close enough to that of state-of-the-art lithium-ion batteries.
Phosphate based cathode materials appear to constitute first-rank candidates for green and sustainable cathode materials for NIBs and KIBs. Here, we report a one-step synthesis route using a spray drying method to produce highly homogeneous, crystalline, and impurity-free phosphate-carbon composite cathode materials for NIBs/KIBs with enhanced Na/K-ion diffusivity and kinetics. The overall electrochemical performances of the Na-ion and K-ion cells have been improved by the addition of the carbon sources/allotropes during the cathode material preparation. Spray drying synthesis is a simple and efficient approach that allows preparing composite electrode material with high homogeneity and crystallinity. Indeed, spray drying ensures the simplification of synthesis and scalability of electrode materials and the realization of Na-ion and K-ion batteries systems with lower cost and enhanced electrochemical performance (1-5).
References
1. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076. https://doi.org/10.3390/ma11071076.
2. N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini. Electrochimica Acta 228 (2017) 319–324. https://doi.org/10.1016/j.electacta.2017.01.026
3. J. Bodart, N. Eshraghi, T. Carabin, B. Vertruyen, R. Cloots, F. Boschini, A. Mahmoud. J. Power Sources 480 (2020) 22905. https://doi.org/10.1016/j.jpowsour.2020.229057
4. A. Mahmoud, S. Caes, M. Brisbois, R. P. Hermann, L. Berardo, A. Schrijnemakers, C. Malherbe, G. Eppe, R. Cloots, B. Vertruyen, F. Boschin. J. Solid State Electrochemistry 22 (2018) 103-112. https://doi.org/10.1007/s10008-017-3717-x
5. M. Brisbois, S. Caes, M. T. Sougrati, B. Vertruyen, A. Schrijnemakers, R. Cloots, N. Eshraghi, R. P Hermann, A. Mahmoud, F. Boschini. Solar Energy Materials and Solar Cells 148 (2016) 67–72. https://doi.org/10.1016/j.solmat.2015.09.005
ACKNOWLEDGMENTS
The authors are grateful to the University of Liège and FRS-FNRS for the financial support. Part of this work was supported by the Walloon Region under the “PE PlanMarshall2. vert” program (BATWAL 1318146). A.M. is grateful to the Walloon region for a Beware Fellowship Academia 2015-1, RESIBAT no. 1510399, and University of Liége
Spray drying method for high-performance phosphate-based cathode materials for Na-ion and K-ion batteries
No full textNa-ion batteries (SIBs) and K-ion batteries (KIBs) have been considered as a promising alternative for the next generation of energy storage technologies owing to the natural abundance and the homogeneous geographic distribution of sodium and potassium on the earth crust [1]. In addition, SIBs and KIBs show comparable electrochemical performances to Li‐ion batteries (LIBs).
The electrode materials optimization plays a key role in the development of advanced rechargeable batteries. Spray-drying methods is adequate method to prepare electrode materials for Na/K-ion batteries with well controlled particles size and morphology [2]. Spray drying is a cost-effective and easily up-scalable route to prepare homogeneous multi-component powders, thus making it a suitable method to incorporate carbon in the composite powder. Indeed, it is possible to mix the precursors with conductive additives ((MWCNTs, Carbon Black, graphene etc) during the material synthesis [3-5].
In this work, we report the synthesis and the study of Na2FePO4F, Na3V2(PO4)2F3/C and K3V(PO4)2/C cathode materials for Na/K-ion batteries. The effect of the carbon sources on the structural, morphological and electrochemical properties was deeply investigated by combining different characterization techniques (XRD, SEM, TEM, TGA-DSC, Raman spectroscopy, cyclic voltammetry. galvanostatic charge/discharge etc).
References
1- K. Kubota, M. Dahbi, T. Hosaka, S. Kumakura, and S. Komaba, Chemical Record, 18 (2018) 459–479.
2- B. Vertruyen, N. Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini, Materials MDPI,11 (7) (2018) 1076.
3- A. Mahmoud, S. Caes, M. Brisbois, R. P. Hermann, L. Berardo, A. Schrijnemakers, C. Malherbe, G. Eppe, R. Cloots, B. Vertruyen, F. Boschini, Journal of Solid State Electrochem. 22 (2018) 103-112.
4- N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschin, Electrochimica Acta, 228, (2017), 319-324.
5- A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P.‐E. Lippens, F. Boschini, ACS Appl. Mater. Interfaces, 10 (2018) 34202.
Acknowledgments
The authors are grateful to University of Liege and FRS-FNRS for grants. Part of this work was supported by the Walloon Region under the “PE PlanMarshall2.vert” program (BATWAL – 1318146)
A quantitative study on the effects of external geomagnetic fields by using the GeoMagSphere back-tracing code
No full textEvaluation of cosmic ray trajectories and penetration inside the Earth environment is mandatory for estimation of flux by on-orbit detectors as well as of radiation damage on electronics devices and biological tissues, like those of astronauts onboard the International Space Station. We studied the impact of the external magnetic field on the calculation of some parameters like the rigidity cut-off, by a quantitative comparison among several geomagnetic field models. For this purpose we used GeoMagSphere back-tracing code, performing the particle trajectory reconstruction back-in-time from the chosen position and time up to the borders of the magnetosphere. The analysis done points out the need to combine an external magnetic field model with the internal one (usually IGRF). Several external field models have a different impact on the accuracy as well as on the time needed for calculation, important in case of a large amount of back-traced particles. We also studied cosmic ray propagation inside the magnetosphere, separately for quiet and disturbed solar activity periods. We found that during highly disturbed periods and during magnetic storms, rigidity cut-off, as well as cosmic ray flux, can be appropriately evaluated only by using external field models, like that one proposed by Tsyganenko and Sitnov (2005), well describing those particular conditions
Hydrothermal synthesis and electrochemical properties of Fe1.19(PO4)(OH)0.57(H2O)0.43/C cathode material for Li-ion batteries
Get PDFRecent rapid development of the portable electronic devices, growing interest in the electric vehicles and increasing integration the renewable energies required the development of cost-effective and high energy storage systems. Lithium-ion batteries are considered as system of the choice for variety of mobile and stationary applications. However, new electrode materials are demanded to increase the energy density of Li-ion batteries.
This presentation will report on the preparation and study of Fe1.19(PO4)(OH)0.57(H2O)0.43/C ((FPHH/C) composite as positive electrode material with high capacity and long cycle-life [1, 2]. FPHH/C (C= carbon black (CB) and carbon nanotubes (CNT)) composites were obtained by one-step the hydrothermal synthesis route. These cathode materials showed an excellent reversible capacity corresponding to 1.19 Li reaction. This is attributed to the stable and open structure of FPHH and also to the effect of carbon addition (CB and CNT) that improves the electronic percolation of the composite. The study of the reaction mechanism of FPHH/CNT during cycling by combining operando XRD and 57Fe Mossbauer spectroscopy (Figure 1) shows that the insertion mechanism is a monophasic reaction with 10% volume variations associated to the Fe3+/Fe2+ redox reaction [2].
References
1. C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini. Electrochimica Acta 250 (2017) 49-58.
2. A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. ACS Applied Materials and interfaces 10 (2018) 34202-34211
Strategies for the development of high-performance electrode materials for sustainable Li-, Na-, and K-ion batteries
No full textBatteries have become essential in tackling global warming and energy security. Rechargeable Li-ion technology, by having the highest energy density of any such device, is considered as the battery of choice for electric vehicles and large-scale smart grids. However, lithium ion batteries cannot stand alone to fulfill future needs; therefore, it is urgent to develop new energy storage devices with high safety, lower cost, high energy density and green sustainable to realize mobiles and large-scale applications. Due to the high abundance of sodium and potassium, Na-ion batteries and K-ion batteries have recently emerged as highly promising candidates. In this seminar, we present one-step preparation of composite materials using spray-drying or hydrothermal synthesis routes, two techniques which offer easy scaling-up of production. The objective of this presentation is to demonstrate that the addition of the carbon sources/allotropes during the material preparation allows to control the particle morphology and ensures intimate mixture of the active material and conductive carbon that enhance the electrochemical performance of the electrode materials for Li-, Na- and K-ion batteries [1-6].
References
1- N. Eshraghi, A. Mahmoud, F. Boschini, R. Cloots, EP Patent EP2 (2020) 019, 081, 384.
2- N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Electrochimica Acta, 228 (2017) 319–324.
3. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076.
4- C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Electrochimica Acta 250 (2017) 49–58.
5. C. Karegeya, A. Mahmoud, F. Hatert, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. J. Power Sources 388 (2018) 57-64.
6. A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. ACS Applied Materials and interfaces 10 (40) (2018) 34202-34211
Development the iron- and vanadium-based electrode materials for rechargeable Li/Na-ion batteries
Get PDFLithium-ion batteries have been widely applied as a power source for portable and stationary energy storage systems. Na-ion batteries are considered to be an alternative to Li-ion batteries owing to the natural abundance of sodium. New electrode materials are required to increase the energy density of Li/Na-ion batteries. In this study, we report on the one-step synthesis of composite materials using spray-drying or hydrothermal synthesis routes, two techniques which offer easy scaling-up of production. The objective of this presentation is to show that the addition of the carbon sources during the synthesis leads to control the particles size and ensures intimate contact between the active material and conductive carbon that enhance the electrochemical performance [1-6].
In order to study the effect of the carbon on the structural, morphological and electrochemical properties of the prepared materials by a spray-drying [1-3] or hydrothermal methods [4-6]. The crystal and local structure were analyzed by XRD and 57Fe Mössbauer spectroscopy. The morphological properties were characterized by SEM and TEM. The carbon content was determined by TG/TDA and carbon analyzer. The electrochemical properties were studied by impedance spectroscopy and galvanostatic cycling in lithium cells. The mechanism of the first discharge-charge cycle was investigated by combining operando X-ray diffraction and 57Fe Mössbauer spectroscopy
References
1- A. Mahmoud, S. Caes, M. Brisbois, R.P. Hermann, L. Berardo, A. Schrijnemakers, C. Malherbe, G. Eppe, R. Cloots, B. Vertruyen, F. Boschini, J. Solid State Electrochemistry (2017) 1–10.
2- N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Electrochimica Acta, 228 (2017) 319–324.
3. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076.
4- C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, , Electrochimica Acta 250 (2017) 49–58.
5. C. Karegeya, A. Mahmoud, F. Hatert, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. J. Power Sources. 388 (2018) 57-64.
6. A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. ACS Applied Materials and interfaces, (2018) 10.1021/acsami.8b10663
Electrode Materials for Li/Na-ion Batteries: Improving Electrochemical Performance Through Carbon Addition During Synthesis
Get PDFLithium-ion batteries (LIBs) have outperformed other rechargeable battery systems since 1980 and advances in LIBs technology have improved living conditions around the globe. However, Li-ion batteries face many challenges and limitations. Na-ion batteries are considered to be an alternative to Li-ion batteries owing to the natural abundance of sodium. New electrode materials are required to increase the energy density of Li/Na-ion batteries. However, their electronic conductivity usually has to be improved through the preparation of composite powders ensuring intimate contact between the active material and conductive carbon. In this presentation, we report on the one-step synthesis of composite materials using spray-drying or hydrothermal synthesis routes, two techniques which are easily up-scalable[1-6].
In order to evidence the effect of the carbon on the microstructural and electrochemical properties of the prepared materials by a spray-drying [1-3] or hydrothermal methods [4-6]. The crystal and local structures were analyzed by combining XRD and 57Fe Mössbauer spectroscopy. The morphological properties were characterized by SEM and TEM (Figure 1). The carbon content was determined by TG/TDA and carbon analyzer. The electrochemical properties were studied by impedance spectroscopy and galvanostatic cycling in lithium and sodium cells. The reaction mechanism during cycling was investigated by combining operando X-ray diffraction and 57Fe Mössbauer spectroscopy.
References
1- A. Mahmoud, S. Caes, M. Brisbois, R.P. Hermann, L. Berardo, A. Schrijnemakers, C. Malherbe, G. Eppe, R. Cloots, B. Vertruyen, F. Boschini. J. Solid State Electrochemistry 22 (1) (2018) 103-112.
2- N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini. Electrochimica Acta 228 (2017) 319-324.
3. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076.
4- C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini. Electrochimica Acta 250 (2017) 49-58.
5. C. Karegeya, A. Mahmoud, F. Hatert, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. J. Power Sources 88 (2018) 57-64.
6. A. Mahmoud, C. Karegeya, M. T. Sougrati, J. Bodart, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. ACS Applied Materials and interfaces 10 (2018) 34202-34211
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