Academic literature on the topic 'Anion intercalation'

A new intercalation compound of insect pheromone, valeric acid (VA), based on zinc layered hydroxide (ZLH) as host release material, was successfully prepared through coprecipitation method. The as-produced organic-inorganic nanolayered material, valerate nanohybrid, VAN, shows the formation of a new peak at lower 2θ angle with basal spacing of 19.8 Å with no ZnO reflections, which indicate that the intercalation of anion between the inorganic ZLH interlamellae was accomplished. The elemental, FTIR, and ATR analyses of the nanohybrid supported the fact that the intercalation with the percentage anion loading was calculated to be 23.0% (w/w). The thermal stability property of the resulting nanohybrid was enhanced compared to the unbound anion. Field emission scanning electron micrograph of the ZnO has a nonuniform granular structure but transforms into flake-like structure with various sizes after the intercalation process. Release kinetics of anion from the interlayer of intercalated compound exhibited a slow release behavior governed by the pseudo-second-order kinetic model at different pHs of aqueous media. The valerate anion was released from VAN with the highest release rate at pH 4. These findings provide the basis to further development of controlled release formulation for insect pheromone based on ZLH intercalation.

The synthesis and characterisation of various organic-inorganic nanohybrids are reported in this contribution. The host material was Ca3Fe-LDH prepared by the co-precipitation method.E-cinnamate, E-4-nitrocinnamate orE-2,5-difluorocinnamate anions were the guests. Successful intercalation occurred through the introduction of the guest anion into the interlayer region of the host materials with the dehydration-rehydration method. The obtained nanohybrids were studied by powder X-ray diffractometry (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray fluorescence (EDX) coupled to the SEM instrument and infrared spectroscopy (IR). These methods were used on one hand to prove that intercalation was successful and for the characterisation of the substances on the other. Molecular modelling was used for visualising the possible spatial arrangement of the organic anions.

Nanodimensional layered metal hydroxides such as layered double hydroxides (LDHs) and hydroxy double salts (HDSs) can undergo anion exchange reactions releasing intercalated anions. Because of this, these metal hydroxides have found applications in controlled release delivery of bioactive species such as drugs and pesticides. In this work, isomers of hydroxycinnamate were used as model compounds to systematically explore the effects of anion structure on the rate and extent of anion release in HDSs. Following intercalation and subsequent release of the isomers, it has been demonstrated that the nature and position of substituent groups on intercalated anions have profound effects on the rate and extent of release. The extent of release was correlated with the magnitude of dipole moments while the rate of reaction showed strong dependence on the extent of hydrogen bonding within the layers. The orthoisomer showed a more sustained and complete release as compared to the other isomers.

An organo-mineral nanohybrid material in which the organic moiety is interleaved inside the inorganic lamella was prepared by using phenoxyacetate anions as a guest in the Mg-Al-layered double hydroxide lamella (as an inorganic host) by the self-assembly technique, anion exchange and the reconstruction methods. The powder XRD patterns of the resulted materials show that the basal spacing of the Mg-AI-layered double hydroxide with carbonate as the counter anions expanded from 7.7 ? to around 16.6 ? in the nanohybrid materials. IR studies show that the absorption bands of the resulting materials correspond to the characteristic functional groups of the host and the guest structures. When the two results are taken together, the expansion can be attributed to the intercalation of the phenoxyacetic acid in the inorganic interlamella for the formation of the nanohybrid material. The intercalation of phenoxyacetate anions was also confirmed by thermogravimetric analysis (TG).

Intercalation of oligomeric chromium(III) polycation species in layered tetratitanates was prepared by three steps: 1) ion-exchange of H+ for K+ in potasium tetratitanates, 2) intercalation of n-alchylamine (n-propylamine, n-butylamine, n-amylamine, and n-hexylamine) compounds in layered hydrogen tetratitanates by adding an aqueous solution of 5M n-alchylamine to hydogen titanates with stiring at room temperature, and 3) intercalation of oligomeric chromium(III) polycation species by mixing butylamine-intercalated tetratitanates with an aqueous solution of CrCl3.6H2O at pH various. The procedure was carried out by Chimie Douce method. The results showed that all of n-alchylamine-intercalated tetratitanates crystallize on monoclinic crystal system with the Bravais lattice C. The hight intensity of the first peaks (200) indicated that butylamine and amylamine-intercalated tetratitanates have a remarkably high crystallinity without impurities phase. The interlayered distance (d) and the lattice parameter projected along a increase with increasing the amount of C-atoms in n-alchylamine. At pH=1.3, [CrCl(H2O)5]2+ or [CrCl2(H2O)4]+ species was pillared more efective in layered tetratitanates than [Cr(H2O)6]3+ spesies and just one spesies, Cr(H2O)6]3+ at pH=1.7. On the contrary, [Cr(OH)(H2O)5]2+ or [Cr(OH)2(H2O)4]+ was intercalated more effevtive than [Cr(H2O)6]3+ species at pH=5.3. Keywords: tetratitanates, intercalation, oligomeric chromium(III) species, Chimie Douce.

Layered double hydroxides (LDHs) are anionic clays composed by host layers of positively charged metal hydroxide, in which anions are intercalated to neutralize the charge of the positive layers. Because of the positive charge of the structure and because of their properties of anion exchanges, different anions can be intercalated into the structure. In recent years the ionic conductivity of LDHs was studied for use as the anode material in lithium-ion batteries or PVA/LDH hybrid membranes for fuel cells. However, such studies have reported very low values of the electrical conductivity that is less than 10-3 S cm-1 near room temperature. However, the ion conductivities of LDHs depends on the intercalated anion species and may be affected by difference in the synthesis condition. Moreover, the anion conductivity increases with increasing interlayer distance and as more water is adsorbed by LDH. Within this framework, we have intercalated two ionic liquids, tetramethylammonium hydroxide (TMAH) and 1-buthyl-3-methylimidazolium hydrogen sulfate (Bmim-HSO4) in the interlamellar space with the purpose of increasing the ionic conductivity and decreasing the dependence from the water content. LDH was prepared using the co-precipitation method with controlled pH. The introduction of IL was performed by the intercalation methods. The increase of conductivity was around an order of magnitude in the case of Bmim-HSO4. The LDH-IL can be an interesting material to prepare composite membranes for electrochemical applications.

Intercalation of hydrogen phosphate ( HPO 4) into Mg / Al -Layered Double Hydroxides (LDH) with DodecylBenzeneSulfonate (DBS) was investigated with regard to anion exchange, rehydration and a combination of delamination and anion exchange. HPO 4 could not be intercalated into the interlayer space of LDH with DBS when using either anion exchange or rehydration methods. However, HPO 4 was successfully intercalated into the Mg / Al -LDH using a combination of delamination and anion exchange methods.

Supercapacitors have aroused considerable attention due to their high power capability, which enables charge storage/output in minutes or even seconds. However, to achieve a high energy density in a supercapacitor has been a long‐standing challenge. Here, graphite is reported as a high‐energy alternative to the frequently used activated carbon (AC) cathode for supercapacitor application due to its unique Faradaic pseudocapacitive anion intercalation behavior. The graphite cathode manifests both higher gravimetric and volumetric energy density (498 Wh kg−1 and 431.2 Wh l−1) than an AC cathode (234 Wh kg−1 and 83.5 Wh l−1) with peak power densities of 43.6 kW kg−1 and 37.75 kW l−1. A new type of Li‐ion pseudocapacitor (LIpC) is thus proposed and demonstrated with graphite as cathode and prelithiated graphite or Li4Ti5O12 (LTO) as anode. The resultant graphite–graphite LIpCs deliver high energy densities of 167–233 Wh kg−1 at power densities of 0.22–21.0 kW kg−1 (based on active mass in both electrodes), much higher than 20–146 Wh kg−1 of AC‐derived Li‐ion capacitors and 23–67 Wh kg−1 of state‐of‐the‐art metal oxide pseudocapacitors. Excellent rate capability and cycling stability are further demonstrated for LTO‐graphite LIpCs.

Le propos de ce mémoire traite de la préparation de catalyseurs, obtenus par traitements thermiques de précurseurs HDL intercalés par des anions complexes métalliques. Les métaux concernés sont : Mn, Co, Cu, Ga, Ru, Ir, Pt et leurs complexes sont intercalés dans des matrices [ZnAI], [MgAI] et [CuAI]. La présence du métal actif en catalyse dans l'interfeuillet ouvre une voie alternative à celles où il se trouve soit dans un feuillet soit imprégné. Des méthodes de synthèse, innovantes par l'association d'échange anionique classique et d'échange anionique sous condition hydrothermale, ont été optimisées par l'affinement de nombreux paramètres. Ceci afin d'obtenir des protocoles reproductibles offrant des composés HDL intercalés sans aucune impureté. Un effort a été porté sur la caractérisation de ces composés, et plus particulièrement sur le domaine interlamellaire. Ces caractérisations ont été menées par diffraction des rayons X, spectroscopie Infra-Rouge, UV-visible, XANES et EXAFS aux seuils des métaux intercalés ainsi qu'au seuil du zinc et analyses chimiques élémentaires. Les données récoltées ont permis de modéliser le domaine interlamellaire et de proposer les différentes orientations possibles des anions complexes métalliques dans l'interfeuillet, même lorsqu'ils ont été modifiés lors de l'intercalation. Des études du comportement thermique, des mesures de surfaces BET et de porosité, sont présentées dans un domaine allant de 25° C à 1000° C pour chaque composé. Certains de ces composés montrent une évolution intéressante de leur surface, lors du traitement thermique. Des études de réduction ont été poursuivies par RTP et traitement polyol. Cela a mis en évidence le comportement particulier des composés contenant de la platine. La dernière partie de ce mémoire est consacrée à un test catalytique concernant le composé HDL intercalé par un complexe anionique contenant du cobalt. Les résultats en sont encourageants, bien que le choix de la réaction test ne se soit pas révélé optimal

L’étude cinétique a permis de déterminer le temps d’équilibre atteint lors de la fixation du benzopurpurine 4B sur chaque composé, ainsi que l’ordre de la réaction et la nature du mécanisme de diffusion. Cette adsorption est favorisée par un milieu légèrement basique, et l’augmentation de la température a un effet positif sur l’amélioration des performances maximales de la fixation. L’étude des isothermes d’adsorption de ce colorant, a été établie pour déterminer l’efficacité de cette nouvelle classe d’adsorbants. Ces dernières sont de type L, et les donnés de sorption ont été traitées selon plusieurs modèles, afin de mieux comprendre le mécanisme d'adsorption du colorant sur les différents matériaux. L’analyse des résultats de l’étude thermodynamiques a montré que l’adsorption du colorant sur les différents composés est un phénomène spontané, endothermique et favorable, régie par une adsorption physique pour les matériaux CoFe-CO3/Ec, CoFe-CO3/A et MgAl-CO32- et par une adsorption physico-chimique pour les matériaux CoFe-Ac/p, CoNiFe-Ac/p , et MgAl-500. Ces résultats ont été confirmés par les analyses DRX et IR des différents matériaux avant et après adsorption. En comparant les résultats obtenus pour l’adsorption du colorant sur les différents matériaux, le composé CoNiFe-Ac/p constitue le meilleur adsorbant avec une capacité d’adsorption d’environ 593mg/g. Par conséquent, et compte tenu de l’ensemble des résultats fournis par cette étude, l’hydrolyse forcée en milieu polyol, s’avère une méthode très efficace pour l’élaboration des hydroxydes doubles lamellaire à base de métaux de transition avec une morphologie contrôlée, de taille nanométrique présentant un faible taux d’agglomération, et par conséquent une bonne dispersion de particules et un meilleur pouvoir adsorbant. Ces caractéristiques peuvent être à l’origine de l’application de ces matériaux avec succès dans l’élimination des colorants contenant dans les effluents industriels<br>New layered double hydroxides (LDHs) CoFe-Ac, CoNiFe-Ac, ZnNiFe-Ac and ZnCoFe-Acwith MII/MIII molar ratio of 3, and acetate ions in the interlayer region have been preparedusing forced hydrolysis of acetate metallic salts in a polyol medium. The structure,morphology and properties of as-prepared product were investigated by X-ray Diffraction(XRD), FT-IR Spectroscopy, elemental analysis, transmission Electron Microscopy (TEM),Scanning Electron Microscopy (SEM), thermal analysis (DTA, TGA) and V-visibleSpectroscopy: showed that these nanocomposites present the typical features of hydrotalcitelikestructure, exhibit a turbostratic character and the intercalation of acetate anions into theinterlayer domain has been successfully done, giving an interlayer spacing value of 12.70,12.47, 13.64 and 14.69 Å for CoFe-Ac, CoNiFe-Ac, ZnNiFe-Ac and ZnCoFe-Acrespectively.We can note that there is some difference between the interlayer spacing for all synthesizedphases. That can be explained by the arrangement of inserted species (anions + water) indifferent orientation in the interlayer domain.57Fe Mössbauer spectrometry allows concluding the presence of Fe3+ cations which occupyoctahedral sites and confirming the absence of Fe2+ in the as-prepared compounds.In order to check the capacity of our materials synthesized in polyol medium to exchange theacetate anions inserted in their interlamellar space, anionic exchange in aqueous medium waseffected for CoFe-Ac compound as à model of synthesized LDH. All the physicochemicalmethods of analysis (DRX, IR, ATD/ATG and elemental analysis) carried out on the materialCoFe- Ac /EC (exchanged). The comparison with a lamellar phase containing oFeCO3/Asynthesized in aqueous medium, show a layered double hydroxide compound with aturbostratic disorder, and a new interlamellar distance d003 = 7.67Å which correspondsperfectly with the presence of the carbonate anions and the water molecules in the interfeuilletfield.In the second part of this study, we are interested to examine the capacities of these kinds ofmaterials for the adsorption of an anion dye benzopurpurine-4B-. The adsorption of direct red2 by CoFe-Ac, CoNiFe-Ac LDHs has been examined in order to measure the capability ofthis new organic/inorganic nanomaterial to eliminate this highly toxic azoic class of anionicdyes from wastewater. The sorption capacities of LDHs for Benzopurpurine4B are also compared with those of other adsorbents : CoFe- Ac /Ec, CoFeCO3/A (synthesized in aqueous medium), Mg-Al-CO3/A and its calcined product at 500°C “Mg-Al-500”. The quantity of dye eliminated was found to depend on contact time, pH, initial concentration of dye and heating temperature. The thermodynamic parameters ΔG°, ΔH° and ΔS° werecalculated to predict the nature of adsorption. Results suggested that the Benzopurpurine 4B adsorption on different compounds was a spontaneous and endothermic process. Adsorption kinetic data were tested using pseudo-first order, pseudo-second order, Elovitch’sequation and intra-particle diffusion models. Kinetic studies for all cases showed that the adsorption followed a pseudo-second order reaction. Studies revealed that intra-particle diffusion played an important role in the mechanism of dye adsorption by MgAl-500. Theequilibrium data were analyzed using Langmuir, Freundlich, Tempkin, Elovitch, Dubinin-Radushkevich, Redlich-Peterson and Toth isotherm models. [...] Taking these results into account, we can conclude that prepared LDHs by forced hydrolysis in a polyol medium can be used successfully in the removal of anionic dyes from aqueous solutions

De nouveaux hydroxydes doubles lamellaires (LDHs) contenant des entités oxométallates (Mo, W) intercalées ont été préparés et caractérisés par diffraction des rayons X (DRX), analyse chimique, spectroscopie infrarouge (IR) et EXAFS. Dans les deux cas, des anions M2072- (M = Mo, W) constitués de deux tétraèdres à sommet commun, sont intercalés. L'évolution structurale des phases LDHs contenant des ions oxométallates libres dans l'espace interfeuillet, traitées thermiquement jusqu'à 800'C, a été étudiée. Il a ainsi été montré que les anions oxométallates se greffent à deux feuillets adjacents au voisinage de 200'C. Le comportement thermique de phases contenant des anions carbonate intercalés a également été appréhendé par DRX in et ex situ, spectroscopie IR, analyse chimique et thermogravimétrie couplée à la spectrométrie de masse. Il a été mis en évidence un mono-greffage des anions carbonate aux feuillets. L'intercalation et l'oligomérisation d'anions acrylate dans les LDHs ont également été réalisées. Des différences, de comportement sont observées selon la nature de l'ion substituant du nickel (Fe, Co ou Mn) dans les feuillets. Dans le cas du fer, la phase contenant les monomères intercalés a pu être isolée et caractérisée, alors que dans le cas du cobalt et du manganèse, une polymérisation spontanée, simultanément à l'intercalation dans la matrice, a été observées. Les macromolécules polymérisées in situ ont été extraites par échange anionique, dérivatisées en poly(acrylate de méthyle) et analysées par chromatographie d'exclusion stérique.

碩士<br>國立清華大學<br>化學工程學系<br>103<br>Abstract The thesis aims at studying the electrochemical behavior of anion intercalation into carbon materials and designing the asymmetric supercapacitors based on this energy storage mechanism. The first part introduces using carbon paper (GDL25BC), which is a gas diffusion layer in fuel cell, as an electrode for studying the electrochemical behavior of the anion intercalation. A three-electrode test system with electrolytes system was established and comparaed the electrochemical reaction on the carbon paper positive electrode with results of material analysis in this section. In conclusion: 1. Anion intercalation type carbon paper (GDL25BC) is a high specific capacity and good rate-performance electrode; 2.Carbon paper (GDL25BC) by the rolling process, can be made to flexible electrode. 3. It has a high rate performance and good cycling stability. The second part demonstrates comparing the electrochemical behavior of anion intercalation into commercial graphitic carbons. In summary: 1. Anion intercalation need occur at graphitic carbon materials with a high crystallinity degree, so that the soft carbon is not allowed; 2 Particle size affects on the electrode through charge transfer impedance (Rct) and Warburg diffusion impedance, a large particle size material greatly restricts its rate performance. 3. Mesosphere carbon microbeads (MCMB) has a high crystallinity degree, but also amorphous carbon peak. These amorphous carbon promote electrolyte diffusion transfer in the electrode, so that the electrode performance ratio has been greatly improved. In the third part, worms-like type expanded graphite was selected as new cathode based on the above conclusions. Modify expanded graphite by heat treatment, ultrasonic vibration, pitch carbon coated and phenolic resin coated. Get the best performance sample EG-600Up (expanded graphite treated treatment at 600 ℃, ultrasonic oscillation 4h, 75% pitch coated), it has a high rate capability (3A / g) and discharge stability (500cycle, retention 95.7%). Assembled asymmetric supercapcitors (AC /EG-600Up) which activated carbons as a negative electrode, EG-600Up as a positive electrode, measured in TEABF4 solving in propylene carbonate (PC). It has a good performance on energy density and power density: 51.47Wh / kg, 10.12kW / kg.

碩士<br>東海大學<br>化學系<br>107<br>In recent years, aluminum has been considered as suitable candidate for electrochemical storage devices due to its high volumetric and gravimetric capacities besides its high abudance. The high capacity of aluminum ion battery is attributed to trivalent electrochemical redox reaction (Al3++3e-↔Al). Moreover, it is supported by its density which is around four times the lithium and it can be handled under the air leading to enormous advantages for the battery application, thus extremely improves the safety level of electrochemical storage system. We investigated the electrochemical performance of different graphite materials as cathode for aluminum-ion battery by using in-situ X-ray diffraction and in-situ Raman techniques. The two analytical methods demonstrated that crystallinity of the graphite materials will influence the storage mechanism of AlCl4-. Furthermore, we synthesized expanded graphite (EG) by simple acid treatment and followed by high temperature annealing.The high capacity displayed by EG can be attributed to integreated intercalation and adsorption mechanisms. In-situ XRD and in-situ Raman techaniques were used to speculate the different mechanisms adopted by EG during cycling.

Extended solids encompass all solids in which no well-defined molecular entities can be distinguished. This is the case for metals and alloys, covalently bonded solids like diamond and silicon, and ionic crystals of which the alkali halides are prototypes. Intermediate cases are common, such as crystals consisting of a charged covalent network with counterbalancing cations or anions. Silicates and their analogues are a prime example of often charged networks with partially covalent bonding. An increasing number of solids are known in which both an extended framework and molecular entities exist, with the molecules being embedded in the extended framework. Graphite intercalation compounds and a variety of host/guest complexes are examples of this class. The bonding features in the charge density are pronounced in crystals with extended covalent networks. The availability of perfect silicon crystals has allowed the measurement of uncommonly accurate structure factors, of millielectron accuracy. The data have served as a test of experimental formalisms for charge density analysis, and at the same time have provided a stringent criterion for quantum-mechanical methods. We will start the discussion in this chapter with silicon and its analogues, diamond and germanium, and proceed with the treatment of silicates, and metallic and ionic crystals. In the face-centered cubic structure of silicon, atoms are located at 1/8 1/8 1/8 and at the center-of-symmetry related position of −1/8 −1/8 −1/8.

Magnesium-aluminum (Mg-Al) based layered double hydroxide (LDH) polymer nanocomposites were developed through the implementation of a rehydration technique. Organic anionic surfactant sodium dodecyl sulfate (SDS) and an anionic polymer, poly(styrene sulfonate) (PSS) were used for intercalation in the cationic intergallery spacing of LDH. This rehydration technique was performed by calcination of the LDH precursor for removal of carbonate anion followed by rehydration of organic anionic phase in a nitrogen rich atmosphere. The resulting nanocomposites were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and powder x-ray diffraction (XRD).