La demande actuelle en batteries lithium-ion « tout solide » adaptées aux applications mobiles asuscité d'importantes recherches sur des membranes électrolytes polymères de plus en plussophistiquées. Cette thèse porte sur la synthèse et la caractérisation mécanique, thermique etstructurale de nouveaux matériaux électrolytes polymères nanocomposites résultant de la réticulationpar procédé sol-gel de chaînes de poly(oxyde d'éthylène) (PEO) fonctionnalisées aux deux extrémitéspar des groupements alkoxysilane. Les nano-domaines polysilsesquioxanes ainsi formés par hydrolysecondensation,génèrent un haut degré de réticulation et jouent le rôle de nanocharges, apportant unerésistance mécanique permettant d'incorporer des quantités élevées de plastifiant. En outre, leprocédé sol-gel permet de fonctionnaliser ces nano-domaines avec des groupements de type sulfonateou perfluorosulfonate de lithium, qui fournissent des porteurs de charge Li+ de façon uniforme au seinde la membrane. De plus, l'immobilisation des anions par liaisons covalentes supprime leurcontribution à la conductivité, ce qui assure au sein de l'électrolyte (alors dit single-ion) une conductionunipolaire cationique, indispensable pour éviter ultérieurement la formation de dendrites de lithium aucours des cycles de charge et décharge. L'étude de la conductivité ionique de ces membranes, à l'étatsec ou après gonflement dans le carbonate de propylène, a conduit à une réflexion sur la dynamique ducation lithium au sein des membranes nanocomposites et sur les différentes voies envisageables pouraméliorer les performances de ces électrolytes. / The topical demand in all-solid lithium-ion batteries suitable for portable consumer electronicdevices has triggered extensive research on more and more sophisticated polymer electrolytemembranes (PEM).This PhD work deals with the synthesis and the mechanical, thermal andstructural characterization of new nanocomposite PEM arising from the sol-gel cross-linking ofPEO chains end-capped with alkoxysilane groups. Thus, the polysilsesquioxane nano-domainsformed by hydrolysis-condensation reactions form a high density of cross-links and play the roleof nanocharges, giving rise to mechanical resistance, which allows incorporating high amounts ofplasticizer. Moreover, sol-gel process allows the functionalization of these nanodomains withlithium sulfonate or perfluorosulfonate groups, which supply Li+ charge carriers homogeneouslydispersed throughout the membrane. In addition the immobilization of the anions via covalentbonds prevents them from contributing to the overall conductivity, thus ensuring a single-ionconduction, which is a compulsory condition to prevent the further formation of lithium dendriteson charge-discharge cycles. The ionic conductivity study of the membranes, in the dry state orafter swelling in propylene carbonate, was done. It led to discuss the dynamics of lithium cation inthe nanocomposite membranes and the possible ways to improve their conductionperformances.

<p> A theory of spin waves for the spin structures found in the rare earth metals of hcp crystal structure is described. The theory is developed for the conical spiral spin structure which contains the planar spiral, the nonplanar ferromagnet and the planar ferromagnet as special cases. Included in the Hamiltonian are isotropic and anisotropic exchange interactions, single-ion crystal field terms, and magnetoelastic terms, both of the single-ion type and the two-ion type. Equations of motion for the spin operators are linearized with the help of the random phase approximation which makes it possible to express some spin-wave interaction effects in terms of powers of the reduced magnetization. Expressions for the spin-wave energies are given for the four structures under consideration.</p> / Thesis / Master of Science (MSc)

Le remplacement des électrolytes liquides conventionnels des batteries lithium-ion est un enjeu majeur pour améliorer leurs performances et leur sécurité. Dans ce contexte, ce travail de thèse est focalisé sur la synthèse d’une nouvelle classe d’électrolytes solides organiques : les cristaux liquides ioniques thermotropiques, ainsi que la caractérisation multi-échelle des nanostructures obtenues et du transport ionique. Tout d’abord, nous présentons les structures chimiques choisies pour créer des assemblages de molécules cristal liquide à conduction « single-ion ». Ensuite, nous détaillons l’étude structurale et fonctionnelle, qui a permis d’établir l’organisation supramoléculaire sous forme de phase colonnaire avec des canaux de conduction ionique nanométriques. Des conductivités pouvant atteindre 10-4 S.cm-1 à 70°C ont été obtenues. La dynamique des ions au sein de ces électrolytes a été étudiée à l’échelle moléculaire et nous avons mis en évidence un mécanisme de conduction par saut. La polymérisation des cristaux liquides ioniques pourrait permettre le développement d’électrolytes polymères de type single-ion pour les batteries. / One major issue towards large-scale application of lithium-based batteries concerns their safety which is directly related to the nature of the electrolyte. Solid electrolytes are at present considered as a promising approach to avoid the risks related to the commonly employed liquids. Herein we report the synthesis and the characterization of a promising class of electrolytes: Thermotropic Ionic Liquid Crystals (TILCs). We describe the design and the synthesis of new self-assembled single-ion materials in function of their chemical architecture. We performed a systematic structural and functional properties study, demonstrating the crystal-liquid properties as well as the supramolecular organization into columnar phases. One of the most promising TILC shows a conductivity of 10-4 S.cm-1 at 70°C. The ion dynamics was probed at molecular scale to establish the main features of hopping conduction mechanism. Further polymerization of the TILCs could be applied to develop high performance single-ion polymer electrolytes for Li-ion batteries.

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Considerable efforts are being devoted to designing enhanced molecular magnetic materials, in particular single molecule magnets (SMMs) that can meet the requirements for future technologies such as quantum computing and spintronics. A current trend in the field is enhancing the global anisotropy in metal complexes using single-ion anisotropy. The work in this dissertation is devoted to the synthesis and characterization of new building blocks of the highly anisotropic early transition metal ion V(III) with the aim of incorporating them into heterometallic molecular materials. The results underscore the importance of tuning the local coordination environments of metal ions in order to ensure enhanced single ion anisotropy. A family of mononuclear axially distorted vanadium (III) compounds, A[L_(3)VX_(3)] (3-9) (X = F, Cl or Br, A^(+) = Et_(4)N^(+), nBu_(4)N^(+) or PPN^(+) , L_(3) = Tp or Tp* (Tp = tris(-1-pyrazolyl)borohydride), Tp* = tris(3,5-dimethyl-1-pyrazolyl)borohydride)), and [Tp*V(DMF)_(3)](PF_(6))_(2) were studied. Replacement of the Tp ligand in 3 with the stronger π-donor Tp* results in a near doubling of the magnitude of the axial zero-field splitting parameter D_(z) (D_(z) = -16.0 cm^(-1) in 3, and -30.0 cm^(-1) in 4) as determined by magnetic measurements. Such findings support the idea that controlling the axial crystal field distortion is an excellent way to enhance single-ion anisotropy. High Field-High Frequency EPR measurements on 4 revealed an even higher D value, -40.0 cm^(-1). Interestingly, compound 4 exhibits evidence for an out-of-phase ac signal under dc field. In another effort, a new series of vanadium cyanide building blocks, PPN[V(acac)_(2)(CN)_(2)]∙PPNCl (13) (acac = acetylacetonate), A[V(L)(CN)_(2)] (A^(+) = Et_(4)N^(+), L = N,N'-Ethylenebis(salicylimine) (14), A = PPN^(+), L = N,N'-Ethylenebis(salicylimine) (15), L = N,N'-Phenylenebis(salicylimine) (16), and L = N,N'-Ethylenebis(2-methoxysalicylimine) (17)) were synthesized. Magnetic studies revealed moderate Dz values (-10.0, 5.89, 3.7, 4.05 and 4.36 cm^(-1) for 13-17 respectively). The first family of cyanide-bridged lanthanide containing molecules with a trigonal bipyramidal (TBP) geometry, (Et_(4)N)_(2)[(Re(triphos)(CN)_(3))_(2)(Ln(NO_(3))_(3))_(3)]-∙4CH_(3)CN (19-27 with Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy and Ho) were prepared using the [(triphos)Re(CN)_(3)]^(-) building block, results that add valuable information to our database of compounds with a TBP geometry. Magnetic studies revealed diverse magnetic responses including slow relaxation of the magnetization at zero field for 25 and 26 , an indication of SMM behavior.

The introductory Chapter to this thesis outlines fundamental aspects of 4f lanthanide(III) coordination chemistry, in particular compounds that possess the intriguing properties of slow relaxation of magnetisation, (or the ability to behave as single-molecule magnets, SMMs). The recent renaissance into the study of the magnetic behaviour of 4f-coordination complexes has led to the consideration of utilising organometallic precursors for the development of novel lanthanide containing compounds, which may possess interesting magnetic properties, subsequently forming the basis of Chapter Two. In Chapter Two, the syntheses and structures of the novel lithiated thiolate ligand, lithium triphenylsilylthiolate, (Ph3SiS-Li) (2.1), and the sulfur-bridged, dimetallic dysprosium(III) and gadolinium(III) complexes [(MeCp)2Dy(µ-SSiPh3)]2 (2.2) and [(MeCp)2Gd(µ-SSiPh3)]2 (2.3), are described in detail. The structural and physical properties of these compounds are analysed through NMR, elemental analysis and SQUID magnetometry, alongside supporting theoretical calculations to reveal that compound 2.2 is the first dimetallic, sulfur-bridged SMM reported, giving an energy barrier to the reversal of magnetisation of Ueff = 192 ± 5 K.56bChapter Three reports on the structural development of a series of lanthanide monomers, exhibiting the general motif [Ln(OSiPh3)3(THF)3] (where Ln = Dy(3.4), Er(3.5), Ho(3.6), Gd(3.7), Tb(3.8)), exploiting the siloxide ligand Ph3SiOH through two novel synthetic routes. This Chapter also provides new analytical insight to these complexes by exploring their magnetic properties through a series of SQUID measurements and through the analysis of their electronic properties using air sensitive, variable temperature optical absorption spectroscopy. Compounds 3.4 and 3.5 were revealed to be SMMs, with 3.5 having a much higher thermal barrier to the reversal of magnetisation, Ueff = ~ 28 K, than 3.4, which are supported by theoretical analysis. Chapter Four describes the utility of ligand 2.1 and Ph3SiOH in the context of 3d transition metal cyclopentadienyl chemistry, outlining the syntheses and structures of three distinct compounds; the trimetallic, [Cp2Mn3(µ-OSiPh3)4](4.7), the hetero-cubane tetramer [CpMn(µ-SSiPh3)]4 (4.8) and the dimetallic thiolate-bridged [CpCr(µ-SSiPh3)]2 (4.9) compound. These compounds were formed in reactions exploiting organometallic manganocene and chromocene precursors. Magnetic susceptibility measurements were conducted on these compounds to gain further insight into their structural properties. The magnetic exchange coupling constants for Mn(II) compounds 4.7 and 4.8 were J = - 4.4 cm-1 and J = - 3.0 cm-1 respectively. Furthermore, having demonstrated the use of metal-cyclopentadienyl building blocks in the synthesis of novel SMMs, Chapter Five discusses the possibility of further advancement on the development of this class of magnetic molecules.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22659号 / 工博第4743号 / 新制||工||1741(附属図書館) / 京都大学大学院工学研究科電子工学専攻 / (主査)教授 山田 啓文, 教授 川上 養一, 准教授 杉山 和彦 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

A solid electrolyte is a crucial component of any solid state battery. Polymer gel electrolytes have received increasing attention in recent years due to their high ionic conductivity, flexibility, and improved safety. However, a general tradeoff usually exists between the mechanical properties and ionic conductivity in such materials. Molecular ionic composites (MICs) are a new type of rigid polymer gel electrolyte based on ionic liquids (ILs) and a double helical rigid-rod polyamide, poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT). MICs have high ionic conductivity, high thermal and electrochemical stability, and widely tunable and high tensile modulus even at relatively low polymer content. MICs show great promise as solid electrolytes for solid state batteries. This dissertation describes the preparation and characterization of MIC electrolyte membranes. These transparent, flexible, and tough membranes are prepared through a convenient solvent casting process. A large variety of ILs, including both hydrophilic and hydrophobic examples, are suitable to prepare MIC electrolyte membranes by adjusting the solvents used in the casting process. The prepared membranes show a biphasic internal structure consisting of a PBDT-rich “bundle” phase and an IL-rich “puddle” (interconnected fluid) phase. Similar to the bulk MIC ingots prepared previously through an interfacial ion exchange process, the MIC membranes also have high ionic conductivity and tensile modulus at low polymer content. A MIC membrane composed of 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Pyr₁₄TFSI), LiTFSI, and PBDT in a mass ratio of 8:1:1 is tested as a solid electrolyte for lithium metal batteries. This electrolyte membrane shows high ionic conductivity and high rigidity. The shear storage modulus of this MIC electrolyte membrane only decreases by 35% when heated to 200 °C from room temperature, suggesting great mechanical stability at high temperatures. The electrolyte membrane is successfully used as solid electrolyte for a Li/LiFePO₄ battery working over a large temperature range from 23 to 150 °C, and the discharge capacity retention of the cell is as high as 99% after 50 cycles at 150 °C. By replacing the IL in the MIC with a charge-neutral liquid, single-ion-conducting polymer gel electrolyte composed of PBDT and polyethylene glycol (PEG) oligomer are obtained. Similar to the MICs, these single-ion-conducting materials also have high Young’s modulus and biphasic internal structures. This study reveals that the counter ion (Li⁺ or Na⁺) of the PBDT has a major effect on both the ionic conductivity and modulus of the materials. Due to the stronger intermolecular interactions, LiPBDT-PEG demonstrates lower ionic conductivity but higher Young’s modulus. This dissertation also evaluates the viability of rigid PBDT as a polymer binder for electrodes. Aqueous solution-processed LiFePO₄ electrodes with only 3 wt% PBDT demonstrate stable cycling over 1000 cycles without obvious capacity decay, and the rate capacity of these aqueous solution-processed electrodes are comparable to the electrodes prepared with conventional poly(vinylidene difluoride) (PVDF) as the binder, suggesting PBDT can serve as a potential electrode binder for commercial applications. / A solid electrolyte is a crucial component of any solid state battery. Polymer gel electrolytes have received increasing attention in recent years due to their high ionic conductivity, flexibility, and improved safety. However, a general tradeoff usually exists between the mechanical properties and ionic conductivity in such materials. Molecular ionic composites (MICs) are a new type of rigid polymer gel electrolyte based on ionic liquids (ILs) and a double helical rigid-rod polyamide, poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT). MICs have high ionic conductivity, high thermal and electrochemical stability, and widely tunable and high tensile modulus even at relatively low polymer content. MICs show great promise as solid electrolytes for solid state batteries. This dissertation describes the preparation and characterization of MIC electrolyte membranes. These transparent, flexible, and tough membranes are prepared through a convenient solvent casting process. A large variety of ILs, including both hydrophilic and hydrophobic examples, are suitable to prepare MIC electrolyte membranes by adjusting the solvents used in the casting process. The prepared membranes show a biphasic internal structure consisting of a PBDT-rich "bundle" phase and an IL-rich "puddle" (interconnected fluid) phase. Similar to the bulk MIC ingots prepared previously through an interfacial ion exchange process, the MIC membranes also have high ionic conductivity and tensile modulus at low polymer content. A MIC membrane composed of 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (Pyr14TFSI), LiTFSI, and PBDT in a mass ratio of 8:1:1 is tested as a solid electrolyte for lithium metal batteries. This electrolyte membrane shows high ionic conductivity and high rigidity. The shear storage modulus of this MIC electrolyte membrane only decreases by 35% when heated to 200 °C from room temperature, suggesting great mechanical stability at high temperatures. The electrolyte membrane is successfully used as solid electrolyte for a Li/LiFePO4 battery working over a large temperature range from 23 to 150 °C, and the discharge capacity retention of the cell is as high as 99% after 50 cycles at 150 °C. By replacing the IL in the MIC with a charge-neutral liquid, single-ion-conducting polymer gel electrolyte composed of PBDT and polyethylene glycol (PEG) oligomer are obtained. Similar to the MICs, these single-ion-conducting materials also have high Young's modulus and biphasic internal structures. This study reveals that the counter ion (Li+ or Na+) of the PBDT has a major effect on both the ionic conductivity and modulus of the materials. Due to the stronger intermolecular interactions, LiPBDT-PEG demonstrates lower ionic conductivity but higher Young's modulus. This dissertation also evaluates the viability of rigid PBDT as a polymer binder for electrodes. Aqueous solution-processed LiFePO4 electrodes with only 3 wt% PBDT demonstrate stable cycling over 1000 cycles without obvious capacity decay, and the rate capacity of these aqueous solution-processed electrodes are comparable to the electrodes prepared with conventional poly(vinylidene difluoride) (PVDF) as the binder, suggesting PBDT can serve as a potential electrode binder for commercial applications. / Doctor of Philosophy / Solid state batteries are widely considered as the pathway to next-generation high performance batteries. In a solid state lithium battery, the liquid organic carbonate electrolyte is replaced with a solid electrolyte. Polymer gel electrolytes are a type of potential solid electrolyte that have been widely studied in recent decades. This dissertation describes the application of a rigid polymer in preparing polymer gel electrolytes. This highly charged and rigid polymer is a water-soluble polyamide known as PBDT with a double helical structure akin to DNA. Through a modified solvent casting process, a new type of polymer gel electrolyte, known as molecular ionic composite (MIC), is prepared using PBDT and various ionic liquids. Extra salt (which can contain lithium) can also be incorporated into the MIC membrane. This type of new polymer gel electrolyte is rigid with high tensile modulus even at high temperatures and low polymer (PBDT) content. MIC membranes are used as solid electrolytes for lithium metal batteries working over a wide temperature range from 23 to 150 °C. A rigid polymer gel electrolyte can also be obtained by replacing the ionic liquids in MICs with polyethylene glycol. Besides the application in preparing solid electrolytes, PBDT is also evaluated as a polymer binder for aqueous processed electrodes. Preliminary study reveals that PBDT holds great potential for a range of commercial energy storage applications.

No / Two new complexes, [Fe3(μ3-O)(inicH)6(H2O)3][Gd(NO3)6]·(NO3)4·nH2O (1) and [Fe3(μ3-O)(inicH)6(H2O)3][Dy(NO3)5 (H2O)]·(NO3)5·n(H2O) (2) with two isolated complex moieties, were generated when isonicotinic acid was treated with iron(III) nitrate and the corresponding lanthanide(III) nitrate in water. The structures were determined by single-crystal X-ray diffraction studies. In these compounds, the anionic lanthanide complexes are encapsulated by trinuclear [Fe3(μ3-O)(inicH)6(H2O)3]7+ cationic cluster units, which is facilitated by hydrogen-bonding interactions. Investigation of the magnetic properties reveals that 2 shows slow relaxation of magnetization at low magnetic field (Hdc = 1.0 kOe), with an energy barrier of 23 K originating from a single [Dy(NO3)5(H2O)]2– anion. / Errata: 2014(25): 4228 (http://onlinelibrary.wiley.com/enhanced/doi/10.1002/ejic.201402684)

No / This article corrects http://onlinelibrary.wiley.com/enhanced/doi/10.1002/ejic.201402114. 2014(19): 3065-3071.