Matériaux à hautes performance à base d'oxydes métalliques pour applications de stockage de l'énergie

The heart of battery technology lies primarily in the electrode material, which is fundamental to how much charge can be stored and how long the battery can be cycled. Tin dioxide (SnO₂) has received tremendous attention as an anode material in both Li-ion (LIB) and Na-ion (NIB) batteries, owing to benefits such as high specific capacity and rate capability. However, large volume expansion accompanying charging/discharging process results in poor cycleability that hinders the utilization of SnO₂ in commercial batteries. To this end, engineering solutions to surmount the limitations facing SnO₂ as an anode in LIB/NIB will be presented in this thesis. The initial part of the thesis focuses on producing SnO₂ and rGO (reduced graphene oxide)/SnO₂ through laser pyrolysis and its application as an anode. The following segment studies the effect of nitrogen doping, where it was found to have a positive effect on SnO₂ in LIB, but a detrimental effect in NIB. The final part of the thesis investigates the effect of matrix engineering through the production of a ZnSnO₃ compound. Finally, the obtained results will be compared and to understand the implications that they may possess.Le cœur de technologie d'une batterie réside principalement dans les matériaux actifs des électrodes, qui est fondamental pour pouvoir stocker une grande quantité de charge et garantir une bonne durée de vie. Le dioxyde d'étain (SnO₂) a été étudié en tant que matériau d'anode dans les batteries Li-ion (LIB) et Na-ion (NIB), en raison de sa capacité spécifique élevée et sa bonne tenue en régimes de puissance élevés. Cependant, lors du processus de charge/décharge, ce matériau souffre d'une grande expansion volumique qui entraîne une mauvaise cyclabilité, ce qui empêche la mise en oeuvre de SnO₂ dans des accumulateurs commerciaux. Aussi, pour contourner ces problèmes, des solutions pour surmonter les limites de SnO₂ en tant qu'anode dans LIB / NIB seront présentées dans cette thèse. La partie initiale de la thèse est dédié à la production de SnO₂ et de RGO (oxyde de graphène réduit)/SnO₂ par pyrolyse laser puis à sa mise en oeuvre en tant qu'anode. La deuxième partie s'attarde à étudier l'effet du dopage de l'azote sur les performances et permet de démontrer l'effet positif sur le SnO₂ dans les LIB, mais un effet néfaste sur les NIB. La partie finale de la thèse étudie l'effet de l'ingénierie matricielle à travers la production d'un composé ZnSnO₃. Enfin, les résultats obtenus sont comparés avec l'état de l'art et permettent de mettre en perspectives ces travaux

High performance metal oxides for energy storage applications

Le cœur de technologie d'une batterie réside principalement dans les matériaux actifs des électrodes, qui est fondamental pour pouvoir stocker une grande quantité de charge et garantir une bonne durée de vie. Le dioxyde d'étain (SnO₂) a été étudié en tant que matériau d'anode dans les batteries Li-ion (LIB) et Na-ion (NIB), en raison de sa capacité spécifique élevée et sa bonne tenue en régimes de puissance élevés. Cependant, lors du processus de charge/décharge, ce matériau souffre d'une grande expansion volumique qui entraîne une mauvaise cyclabilité, ce qui empêche la mise en oeuvre de SnO₂ dans des accumulateurs commerciaux. Aussi, pour contourner ces problèmes, des solutions pour surmonter les limites de SnO₂ en tant qu'anode dans LIB / NIB seront présentées dans cette thèse. La partie initiale de la thèse est dédié à la production de SnO₂ et de RGO (oxyde de graphène réduit)/SnO₂ par pyrolyse laser puis à sa mise en oeuvre en tant qu'anode. La deuxième partie s'attarde à étudier l'effet du dopage de l'azote sur les performances et permet de démontrer l'effet positif sur le SnO₂ dans les LIB, mais un effet néfaste sur les NIB. La partie finale de la thèse étudie l'effet de l'ingénierie matricielle à travers la production d'un composé ZnSnO₃. Enfin, les résultats obtenus sont comparés avec l'état de l'art et permettent de mettre en perspectives ces travaux.The heart of battery technology lies primarily in the electrode material, which is fundamental to how much charge can be stored and how long the battery can be cycled. Tin dioxide (SnO₂) has received tremendous attention as an anode material in both Li-ion (LIB) and Na-ion (NIB) batteries, owing to benefits such as high specific capacity and rate capability. However, large volume expansion accompanying charging/discharging process results in poor cycleability that hinders the utilization of SnO₂ in commercial batteries. To this end, engineering solutions to surmount the limitations facing SnO₂ as an anode in LIB/NIB will be presented in this thesis. The initial part of the thesis focuses on producing SnO₂ and rGO (reduced graphene oxide)/SnO₂ through laser pyrolysis and its application as an anode. The following segment studies the effect of nitrogen doping, where it was found to have a positive effect on SnO₂ in LIB, but a detrimental effect in NIB. The final part of the thesis investigates the effect of matrix engineering through the production of a ZnSnO₃ compound. Finally, the obtained results will be compared and to understand the implications that they may possess

Investigation on Tin based oxides as potential anode material for Li and Na ion batteries

The heart of battery technology lies primarily in the electrode material, which is fundamental to how much charge can be stored and how long the battery can be cycled. Tin dioxide (SnO2) has received tremendous attention as an anode material in both Li-ion (LIB) and Na-ion (NIB) batteries, owing to benefits such as high specific capacity and rate capability. However, large volume expansion accompanying charging/discharging process results in poor cycability that hinders the utilization of SnO2 in commercial batteries. To this end, engineering solutions to surmount the limitations facing SnO2 as an anode in LIB/NIB will be presented in this thesis. The initial part of the thesis focuses on producing SnO2 and rGO (reduced graphene oxide)/SnO2 through laser pyrolysis and its application as an anode. The following segment studies the effect of nitrogen doping, where it was found to have a positive effect on SnO2 in LIB, but a detrimental effect in NIB. The final part of the thesis investigates the effect of matrix engineering through the production of a ZnSnO3 compound. Finally, the obtained results will be compared and to understand the implications that they may possess.Doctor of Philosophy (IGS

Template-directed synthesis of transition metal oxide (TMO)/ordered mesoporous carbon (OMC) composite as anode material in lithium ion battery

In this report, we studied a simple and general method of impregnating different weight percent of Transition Metal Oxide (TMO) into the pores of Ordered Mesoporous Carbon (OMC). TMOs were chosen for this study owing to its high theoretical capacity and OMC is used to alleviate the volume swing generated during the charge-discharge process suffered by most TMOs. Two types of TMOs namely: Iron Oxide and Cobalt Oxide were studied. Various composition of composites ranging from 27.8 wt% Fe3O4-OMC, 65.9 wt% Fe3O4-OMC composite, 27.3 wt% CoO-OMC and 56.8 wt% CoO(Co3O4)-OMC have been prepared using the simple synthesis method and characterized using SEM, XRD and TGA. Cyclic Voltammetry (CV) was carried out to determine the potential at which redox reaction takes places during charging/discharging. Electrochemical performance test was also carried out to understand how the cycability of both TMO-OMC composites vary with increasing wt % of TMOs. It was found that a higher wt % of oxide (in both cases) would give rise to a more stable cycling performance at the 50th cycle. A possible reason mentioned in literature would be attributed to the slow buildup of the organic polymeric/gel-like layer due to higher amount of inaccessible active material.Bachelor of Engineering (Materials Engineering

Laser pyrolyzed SnO2 nanoparticles as anode material in Sodium ion Batteries

International audienc

Laser pyrolyzed SnO2 nanoparticles as anode material in Sodium ion Batteries

International audienc

Recent developments in electrode materials for sodium-ion batteries

The rapid consumption of non-renewable resources has resulted in an ever-increasing problem of CO2 emissions that has motivated people for investigating the harvesting of energy from renewable alternatives (e.g. solar and wind). Efficient electrochemical energy storage devices play a crucial role in storing harvested energies in our daily lives. For example, rechargeable batteries can store energy generated by solar cells during the daytime and release it during night-time. In particular, lithium-ion batteries (LIBs) have received considerable attention ever since their early commercialization in 1990s. However, with initiatives by several governments to build large-scale energy grids to store energy for cities, problems such as the high cost and limited availability of lithium starts to become major issues. Sodium, which also belongs to Group 1 of the periodic table, has comparable electrochemical properties to Lithium, and more importantly it is considerably more accessible than lithium. Nonetheless, research into sodium-ion batteries (NIBs) is currently still in its infancy compared to LIBs, although great leaps and bounds have been made recently in terms of research and development into this technology. Here in this review, we summarize the recent advancements made, also covering the prospective materials for both the battery cathode and anode. Additionally, opinions on possible solutions through correlating trends in recent papers will be suggested.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore)Published versio

Reserving interior void space for volume change accommodation : an example of cable-like MWNTs@SnO2@C composite for superior lithium and sodium storage

Reserving interior void space in the cable-like structure of multiwalled carbon nanotubes-in-SnO2-in-carbon layer (MWNTs@SnO2@C) is reported for the first time. Such a design enables the structure performing excellent for Li and Na storage, which benefit from the good electrical conductivity of MWNTs and carbon layer as well as the reserved void space to accommodate the volume changes of SnO2.Published versio

ZnFe2_2O4_4 nanoparticles synthesis by laser pyrolysis: interest as new anode material for lithium-ion batteries

International audienceThe development of portable devices, electric vehicles and renewable energies has motivated research works about energy storage for years. Existing lithium-ion batteries cannot reach sufficient energy density to address the needs for such applications. One of the issues limiting the energy density is the low specific capacity of the graphite anode (372 mAh.g$^{-1}$). Mixed-transition metal oxides with a spinel structure (AB$_2$O$_4$-A, B transition metals) appear as a promising solution to replace graphite with a higher theoretical capacity (between 750 and 1000 mAh.g$^{-1}$). Nanostructuration of these compounds was studied to maintain mechanical stability and to enhance lithiation kinetics. ZnFe$_2$O$_4$ is an interesting substitute to graphite as the storage mechanism gives rise to a theoretical capacity of 1001 mAh.g$^{-1}$ and among various oxides, ZnFe$_2$O$_4$ is cheap, abundant and non-toxic. Compared with oxides like Fe$_2$O$_3$, the combination of two transition metals contributes to lower the working voltage vs. Li/Li$^+$ (1.5V for ZnFe$_2$O$_4$ vs. 2.1V for Fe$_2$O$_3$). ZnFe$_2$O$_4$ nanoparticles were synthesized by laser pyrolysis. In this process, an aerosol containing precursors droplets produced by a nebulizer, is flown into the reactor with a carrier gas. In the reactor, a 10.6 $\mu$m-CO$_2$ laser beam decomposes the precursors to obtain nanopowders which are then collected on a filter. The key advantage of laser pyrolysis is the ability to obtain nanomaterials in large scale with a high purity while controlling the grain size with the appropriate parameters. Solutions containing Zn(NO$_3$)$_2$.6H$_2$O and Fe(NO$_3$)$_3$.9H$_2$O dissolved in deionized water were used for the synthesis of ZnFe$_2$O$_4$ nanoparticles. Ethylene was used as sensitizer gas to absorb the CO$_2$ laser and allow the decomposition of the precursors whereas air and argon were tested as carrier gases. Powders of different morphologies and crystallinities were obtained and characterized by XRD, SEM, EDX, HRTEM and XPS. ZnO and Fe$_2$O$_3$ were also synthesized to compare their electrochemical performances with those of ZnFe$_2$O$_4$. All the results were compared with literature

Laser Pyrolysed N-Doped SnOx Nanoparticles with Enhanced Conductivity and Stability As Anode in Li-Ion Batteries

International audienceA novel one-step laser induced pyrolysis method was utilized for the synthesis of pristine SnO2 and p-type conduction N-doped SnOx nanoparticles. Most reports on doping of SnO2 focuses on subtition of Sn with other metallic, while replacement of O is uncommon due to difficulty in synthesis. In particular, laser pyrolysis made the synthesis of N-doped SnO2 possible by the high thermal gradient between the reaction zone and chamber wall to limit particle growth, as well as a brief contact of N atoms and SnO2 under extermely high temperature. The presence of N atoms during the rapid synthesis process substitutes the O2- anion and is hypothesized to improve conductivity of the material. The sample with 3% of N-doping exhibited optimum performance, with high initial and reversible capacities of 1899 and 1241 mAh g-1 respectively. Even when tested at a current density of 10 A g-1, SnO2+N3% can deliver a specific capacity as high as 522 mAh g-1. Moreover, a capacity of 1192 mAh g-1 can be retained at end of the 500th cycle. The cyclability and rate performance of the carbon free SnO2 nanoparticles are by far one of the best reported thus far. Interestingly, SnO2+N8% demonstrated the worst rate capability, which indicates that there could be an optimum doping concentration. The superior performance in SnO2+N3% could be credited to the presence of hole donating N atoms directly situated within the structure of SnO2 and the small particle sizes which permits rapid ion diffusion while preventing pulverization and agglomeration. Ex-situ TEM and XAS will be utilized to further understand correlation between structural properties with enhancement in performance