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Understanding the pulsed discharge behavior of low-rate lithium coin cells in wireless sensing systems is critical to prolong the operating life and/or reduce the size of battery-powered WSs. This dissertation presents the battery transient analysis for a sensor duty cycle, experimental studies for sustained pulse discharge cycling, and investigation on recharge strategies for a battery/power harvesting hybrid system for WSs. The transient behavior of the lithium coin cells during pulse discharge and subsequent relaxation was investigated with single-pulse experiments and theoretical analysis. The voltage response for a pulsed discharge had two parts: a region of rapid voltage change and a region of slower change. The magnitude of the rapid voltage losses was associated with ohmic and interfacial resistances. Solid phase diffusion in the cathode was found to be the major contributor to the "slow" transient voltage change that occurred during and after a pulse. An analytical model was developed to describe the time-dependent voltage and the corresponding non-uniform concentration distribution for the thick porous electrode. A fit of the analytical model to experimental data permitted an estimate of the solid phase diffusivity. Independent fitting of the pulse data and relaxation data both yielded a diffusivity of D ~ 4×10-11 cm2/s, which agreed well with measured values reported in literature. The interactive effect of battery characteristics and WS operating conditions was investigated during sustained pulsed-discharge cycling. At low standby currents (≤50 μA), the influence of the standby current on the operating voltage and battery capacity was negligible. The pulse current had a significant impact on the lower voltage and determined the maximum capacity that could be extracted from a battery regardless of the duty cycle factor. For each pulse length studied, the battery capacity increased as the standby time increased, until a maximum capacity was reached, which could not be increased by further increase in the standby time. The minimum standby time for full (or near full) relaxation for duty cycles with different pulse length was found to correlate well with ratio ts/tp2. Battery pulse discharge-recharge cycling as would occur in a hybrid power system was investigated, and the recharge strategies were evaluated in terms of capacity loss over cycling and energy efficiency. Results from the cycling tests suggested the importance of a rest period between the discharge and charge step of a cycle. PRCR cycling with a 2 s rest period could lower the capacity loss to 25% or less of that of PC cycling with no rest period over 10,000 cycles. Cycling the battery at 80% SOC rather than at 100% SOC (3.1 V) significantly reduced the capacity loss during cycling.

Ce travail porte sur l’étude de la propagation de décharges couronnes impulsionnelles à pression atmosphérique dans les milieux poreux et/ou alvéolaires. Face à la complexité des phénomènes mis en jeu, liés aux interactions entre la décharge et les surfaces du matériau qui la confine, nous proposons l’étude de décharges confinées par des structures élémentaires. L’étude du confinement radial des décharges, assuré par un large panel de capillaires, a été réalisée. Des diagnostics électriques et optiques de pointe permettent d’étudier la propagation de la décharge au sein des différents capillaires. La corrélation entre ces diagnostics a même permis des mesures de vitesse de propagation au sein de capillaires opaques. Les résultats montrent que la propagation de la décharge dépend grandement de la géométrie des capillaires et des paramètres électriques de génération de la décharge. Dans le cas de sections carrées ou rectangulaires, les arêtes induisent un renforcement local du champ qui attire la décharge. Dans le cas de capillaires cylindriques, le diamètre interne est le paramètre crucial qui détermine aussi bien la structure de la décharge que sa vitesse de propagation. Quelle que soit la nature du capillaire, la propagation présente alors une vitesse optimale à tout autre paramètre constant pour une valeur donnée du diamètre interne. Dans le cas du verre, la vitesse est maximale pour un diamètre interne de 200 µm. L’épaisseur et la permittivité diélectrique du capillaire possèdent également une influence sur la propagation de la décharge radialement confinée. Ainsi, diminuer l’épaisseur ou la permittivité diélectrique engendre une accélération de la décharge. Si l’épaisseur est très faible, la décharge peut même se déconfiner pour se propager à l’extérieur du capillaire. Une étude spectroscopique complémentaire montre que la réduction du diamètre de confinement implique une augmentation de la température du plasma, ce qui pourrait contribuer à l’obtention de ce profil de vitesse en fonction du diamètre de confinement. L’étude du confinement axial des décharges a ensuite été réalisée en insérant des membranes de différentes natures et caractéristiques, perpendiculairement à l’axe pointe plan. Les résultats montrent que la décharge présente une propagation en trois étapes : pointe/membrane, radialement au voisinage de la membrane, puis membrane/plan. Dans cette étude, nous avons mis en évidence l’importance du critère poreux ou non de la membrane. Dans le cas poreux, la propagation de la décharge dans l’ensemble du gap est continue, même pour des pores de l’ordre de la dizaine de µm. Dans le cas non poreux, la propagation est discontinue, et il est nécessaire pour assurer la propagation dans l’ensemble du gap qu’un ré-allumage ait lieu de l’autre côté de la membrane. Après l’instant de l’impact sur la membrane, la décharge marque un arrêt qui correspond à la réorganisation des charges et à la restructuration du champ électrique dans le gap. Elle se propage ensuite radialement au voisinage de la membrane en plusieurs fronts d’ionisation. Si les conditions de claquage sont réunies dans le volume membrane/plan, alors un ré-allumage apparaît à partir de la membrane pour atteindre le plan. L’étude de ces ré-allumages semble montrer l’importance de la position de la membrane au sein de l’espace inter-électrodes et de la dynamique des charges aux surfaces de la membrane. Plus on diminue la distance membrane/plan, plus il est facile d’en observer. Nous montrons également que la diminution de la permittivité diélectrique de la membrane ou l’augmentation de son épaisseur, semble augmenter la probabilité de ces ré-allumages. Dans le cas poreux, nous avons également mis en évidence l’influence de la taille des pores de la membrane sur l’ensemble des étapes de propagation. Lorsque la porosité est inférieure à 100 µm la propagation de la décharge est ralentie du fait de la difficulté de la décharge à traverser directement le matériau. / This study is an attempt to understand the mechanisms involved in the propagation of pulsed corona discharges at atmospheric pressure inside porous and/or alveolar media. Due to the complexity of these phenomena which hardly depends on plasma/surface interactions, the study was focused first on the propagation inside basic structures of confinement, before doing it in more complex media, such as monolithic cordierites or foams. Therefore, capillaries have been used to radially confine the discharge propagation. Thanks to highly resolved optical and current diagnostics, we succeed in describing precisely the propagation. A correlation of these diagnostics allowed us to measure propagation velocity inside opaque media. Results show that geometry is the key parameter which both governs the discharge structure and the propagation velocity. Electrical parameters of the discharge ignition have a great role in the propagation also. In case of square and rectangular capillaries, the local electric field enhancement due to edges attracts the discharge. In case of round capillaries, the internal diameter becomes the key parameter which governs the pattern of the discharge and its velocity. Whatever the kind of capillary used, the velocity of propagation shows an optimal value for a given internal diameter, at all others parameters constants. In case of glass capillaries, this maximum value is obtained for a 200 µm internal diameter. Parameters such as wall thickness or dielectric permittivity have also an influence on the propagation velocity. The decrease of the thickness or the dielectric permittivity implies an increase of the propagation velocity. If the thickness is small enough, we observe that the discharge is able to propagate outside the tube. A complementary spectroscopic study of that kind of discharge shows that the plasma temperature depends on the internal diameter, and warming observed for smallest internal diameters could contribute to the internal diameter/velocity of propagation relation. The study of the axial confinement of the propagation of the discharge has been made thanks to different kinds of dielectric membranes, perpendicularly inserted between the electrodes. Results show that the propagation of the discharge is a three step process: tip to membrane propagation, radial propagation near the membrane surfaces, and membrane to plane propagation under specific conditions. The porous feature of the membrane has a key role in the propagation. In case of porous membranes, the whole propagation in the gap is continuous, even for the smallest porosities under investigations (~10µm). In case of non porous films, the propagation by three step processes is no more continuous, and the propagation in the entire gap needs a re-ignition of the discharge on the other side of the membrane. After its impact on the membrane, the discharge stops on the dielectric while the charges and the electric field are self reorganized. Then a radial propagation of several ionization waves starts near the membrane surface. If the disruptive voltage is reached behind the obstacle, a re-ignition could occur in the membrane/plane gap and reach the cathode. Investigation on these reignition conditions shows that the key parameters seem to be the position of the membrane inside the gap and the dynamics of the surface charges on the membrane. Closer is the membrane to the plane, higher is the probability of seeing re-ignitions. Results also show that the decrease of the dielectric permittivity or the increase of the membrane thickness leads to more re-ignition events. In case of porous membrane, the pore size is the main parameter which will influence the propagation. When the pore size is below 100 µm, the discharge propagation is slower due to the discharge difficulties to penetrate totally inside the material.

The doctoral thesis deals with an experimental study of several diagnostic techniques intended for plasma diagnostics and diagnostics of thin films during reactive sputter deposition. A relatively novel probe diagnostic technique called Floating harmonic probe for measurement of the ion density and electron tem- perature in technological low-temperature plasma is studied. A Langmuir probe is commonly used, however, its application in conditions where non-conducting films are being deposited can be problematic or unreliable. The floating harmonic probe measurement technique deals with this inherent problem of the Langmuir probe. The Floating harmonic probe results are compared to those obtained by a classical Langmuir probe in non-reactive DC continuously driven discharge, and its applicability in reactive regime during deposition of iron oxide thin films is proved. The work deals also with a modification of the Floating harmonic probe called Phase Delay Harmonic Analysis Method which is intended for diagnostics of pulsed driven discharges. The second part of the thesis is devoted to a new proposed method for in-situ diagnostics of thin films. This method monitors the capacitance and resistance of a thin film during deposition up to the frequencies in the kHz range. This new method could be used for...

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The purpose of this dissertation is to — on occasion very literally — shine a light on processes that occur in non-thermal plasmas containing CO2, mostly for CO2 conversion. In particular, the focus lies on the transient behaviour of these discharges: how do these systems evolve over time before they settle in a (non-thermal) equilibrium. In addition to that, it analyses trends in the field of plasma-catalytic CO2 conversion as a whole to evaluate the current state-of-the-art, but also presents a new platform for the community to contribute and collaborate on, to facilitate cross-comparison between disparate experiments. The first part consists of experiments performed on: (a) an atmospheric pressure nanosecond repetitively pulsed (NRP) discharge for CO2 conversion, and (b) a test bed system for a remote CCP plasma source for plasma-enhanced atomic layer deposition (PE-ALD) of trimethylaluminium (TMA). The common theme in these experiments is a focus on the application of time-resolved, in situ diagnostics to study transient behaviour in the systems under investigation. The main diagnostics employed for such measurements are optical emission spectroscopy (OES) and laser induced fluorescence (LIF), which can provide complementary results when used in conjunction. In particular, this work presents the following results: A study of the evolution of emission from an NRP discharge (using OES), establishing both electron densities (by Stark broadening of atomic oxygen and carbon lines) and gas temperatures (by the N2 second positive system) as the discharge evolves from a breakdown phase to a spark phase. It furthermore explores the changes to these properties when operating in burst mode, where a subsequent pulse experiences a memory effect from the preceding one, which has been shown to be conducive to efficient conversion in literature. A study into the effect on energy efficiency of CO2 conversion by alternating the power modulation in an NRP discharge. Crucially, using CET-LIF (collisional energy transfer LIF) and OES it is shown that while power deposition to the discharge occurs in the order of 100 ns in the discharge, CO2 dissociation occurs on a timescale beyond a microsecond. This indicates that instead of direct electron impact, molecular-excitation kinetics play an important role under these conditions for CO2 dissociation. By shortening the time between pulses in a burst (down to 33 us in the work), these mechanisms can be further enhanced, by prolonging the quasi-‘metastable’ state of the system. The application of LIF in a PE-ALD process plasma along with OES, where diffusion profiles were measured close to the substrate surface with local time-resolved measurements of the OH ground state density. These indicate that the investigated surface reactions finish on a timescale of 100 ms, faster than would be indicated by OES which effectively measures emission from the bulk plasma after diffusion of reaction products away from the surface. The second part of this work is an open access database on plasma(-catalytic) CO2 conversion that is instrumental in identifying and verifying trends in experimental data, but also stresses the importance of rigorous reporting of essential parameters in literature. The approach in literature is diverse: some studies focus more on a mechanistic understanding of the fundamental processes, whilst others already focus on process tailoring and optimization for industrial applications. Trends observed in earlier review papers are observed as well and can now be trivially reproduced. The database platform (https://db.co2pioneer.eu) is put forward as a new tool for the community to easily cross-compare and contextualize experimental outcomes and strongly encourages new contributions. Based on the 196 papers included at the time of publication, a number of observations and recommendations can already be made. Chief among those is a clear and present need in the field for a more fundamental understanding of plasma-catalysis interaction, to develop techniques and criteria that are properly suited to test the synergy of both, rather than relying on methods from e.g. traditional thermal-catalysis. Also in this instance, local, time-resolved diagnostics may play a key role, but their implementation will be challenging.

Ces dernières années un nouveau type de décharges hors équilibre thermodynamique, aptes à générer des micro jets de plasma se propageant en atmosphère libre, a suscité beaucoup d’intérêt dans la communauté scientifique. Ces micro jets, produits dans des structures type décharge à barrière diélectrique, ont des propriétés particulièrement intéressantes, tant sur le plan de la physique des plasmas que sur celui des applications, en particulier pour des applications biomédicales ou de traitement de surface.Dans ce travail de thèse il est démontré que ces jets de plasma correspondent à la propagation à grande vitesse d'un front d'ionisation sans déplacement de matière. Une caractérisation des propriétés des jets (vitesse et distance de propagation) a été effectuée en fonction de la tension appliquée, du débit, de la composition du gaz, et de la géométrie de la décharge. La distribution spatio-temporelle des espèces réactives produites par le jet a été mesurée, et en particulier celle de l'état métastable He (2³S) mesuré par absorption laser. Des densités comprises entre 1.10¹² et 5.10¹³ cm-³ ont été obtenues pour l’état He (2³S). Sa distribution est annulaire à la sortie de la structure de la décharge et se referme le long du jet. La densité maximale est obtenue à une distance correspondant à la moitié de la zone où les atomes métastables sont présents, ce qui est en contradiction avec les modèles actuels. De plus, afin de mieux comprendre la physique des jets de plasma, nous avons fait interagir deux jets placés l’un en face de l’autre. L'étude de la contre propagation de deux jets révèle qu’il existe une distance minimale d'approche laissant entre eux une zone exempte de plasma. Après l’extinction des deux plasmas, une seconde décharge s’amorce exactement dans cette zone. Une étude détaillée couplant diagnostics électrique, imagerie ultra-rapide et spectroscopie d'émission nous a permis de montrer que cette décharge secondaire est due à une inversion de polarité conduisant à la création transitoire d'un piège à électrons.Dans le but d'aborder l'étude des applications des jets de plasma au domaine biologique, nous avons également étudié la dégradation de l’ADN plasmidique par un jet de plasma. Nous avons mis en évidence que ce type de plasma induit majoritairement des cassures simples et doubles brins, alors que très peu d’oxydations de base ou de sites abasiques sont observés, ceci même avec l’ajout de quelques pourcents d’oxygène dans le gaz. / Micro plasma jets operating at atmospheric pressure in free atmosphere have recently attracted great attention because of their numerous advantages. In fact, micro plasma jets can be operated stably at atmospheric pressure and propagated over some centimeters in a free atmosphere. Moreover, these jets are non-thermal plasmas and create numerous reactive species. These properties allow to use this kind of plasma in many applications, such as surface treatment, decontamination, and plasma medicine.In this work it is shown that these micro plasma jets correspond to the fast propagation of an ionization front with no displacement of matter. A characterization of the plasma proprieties (e.g. distance and velocity of propagation) has been done as a function of the applied voltage, gas flow, gas composition and discharge geometry. The spatiotemporal distribution of the reactive species created by the plasma has been measured, with a special focus on the helium metastable atoms which have been measured by absorption laser spectroscopy. The helium metastable atom densities obtained are in the range of 1.10¹² to 5.10¹³ cm-³. Thanks to a very good spatiotemporal resolution, we have done a time-resolved full cartography of the plasma. This allowed us to show that the helium metastable atom distribution is annular near the nozzle and becomes circular as the plasma propagates. The maximum helium metastable atoms density has been measured at about half of the distance where the helium metastable atoms are present. This observation is in contradiction with results reported by numerical models. To gain further insight into the physical processes of the plasma, we have placed two micro plasma jets face to face. This study showed that both plasmas interact in such a way that they never come into contact, letting a space free of plasma between them. Moreover, we revealed that after the extinction of the plasmas, a second discharge is ignited in the previously free space. Fast imaging, spectroscopy diagnostics and electrical measurements showed that this second discharge is due to a polarity reversal, which creates an electron trap. Aiming the study of the application of micro plasma jets in the plasma medicine field, we have studied the degradation of plasmid DNA by our plasma jet. We observed that the plasma treatment leads mostly to single and double strands breaks, and to very little base oxidation and abasite site, even when oxygen is added into the gas mixture.

摘要 i Abstract ii 誌謝 iv 表目錄 vii 圖目錄 1 一、 緒論 6 1-1前言 6 1-2研究動機與目的 7 1-3氫氧化鋁介紹 8 1-3-1氫氧化鋁結構 9 1-3-2氫氧化鋁之應用 10 1-4氧化鋁介紹 11 1-4-1氧化鋁晶型及結構 13 1-4-2氧化鋁之應用 16 二、 文獻回顧 17 2-1電漿定義及特徵 17 2-1-1非熱電漿之理論 21 2-1-2液相脈衝電漿之原理 24 2-1-3顆粒形成流程 28 2-1-4電漿法製備無機物粉末 30 2-2 製備α相氧化鋁粉末 41 2-2-1拜耳法 43 2-2-2溶膠凝膠法 48 2-2-3水熱法 50 2-2-4機械球磨法 56 2-2-5沉澱法 57 2-2-6燃燒法 59 三、 實驗方法與步驟 60 3-1實驗藥品與設備 60 3-2研究內容 63 3-3實驗流程與架構 65 3-4 本實驗設計之綠能特色 68 四、 結果與討論 69 4-1 氫氧化鋁之產量及反應機構 69 4-2氫氧化鋁之X-Ray繞射儀分析(X-Ray Diffractometer,XRD) 74 4-3氫氧化鋁之EDS(X-Ray energy dispersive spectrometer)分析 77 4-4氫氧化鋁之FE-SEM分析 78 4-5氫氧化鋁之粒徑分析 91 4-6氫氧化鋁之比表面積分析分析 94 4-7氧化鋁之鍛燒溫度探討 98 4-8氧化鋁之持溫時間探討 105 4-9氧化鋁添加硝酸銀之探討 111 4-10氧化鋁添加造孔劑之探討 118 五、 結論 124 六、 未來工作 126 參考文獻 127

Ces dernières années, les missions spatiales bénéficient d'un regain d'intérêt. Cependant, lorsqu’arrive laphase d’entrée dans l’atmosphère, nous faisons encore face à d’importantes difficultés. Afin de répondre àce problème, une nouvelle technique est proposée : le contrôle par plasma pour augmenter la force detraînée sur le véhicule et ainsi, décroître sa vitesse. Dans cette thèse, un actionneur plasma est testé danstrois écoulements supersoniques (N1(M2-8Pa), N2(M4-8Pa) and N3(M4-71Pa)) et un hypersonique (M20-0.062Pa), ces écoulements étant simulés par la soufflerie MARHy.L’actionneur plasma induit des modifications de l’écoulement autour du modèle étudié, comme unemodification de la géométrie de l’onde de choc et une augmentation de l’angle de choc. Afin de mieuxcomprendre les phénomènes gouvernant ces modifications, la pression Pitot, la température surfacique etvolumique, les données électroniques et des mesures spectroscopiques ont été analysées. Les résultatsmontrèrent que deux types d’effets interviennent : thermiques (surface et volume) et l’ionisation. De plus, il aété démontré que ces effets n’ont pas la même importance suivant les conditions d’écoulements.L’actionneur plasma lui-même a été modifié dans un but d’amélioration. En particulier, deux types degénérateurs ont été étudiés pour alimenter la cathode : DC et pulsé. Finalement, il est montré que pour unepuissance de décharge de 80 W, une augmentation de 13% de la traînée et donc, une diminution de plus de25% des flux de chaleur peuvent être attendus. Par conséquent, les actionneurs plasma semblent être descandidats idéaux pour les missions spatiales et les (r)entrées atmosphérique. / Space missions are arousing renewed interest in these recent years. However, when coming to the entryinto the atmosphere, major issues are still to be considered. To answer this problem, a new Entry DescentLanding technique is proposed: plasma actuation to increase the drag force over the vehicle body and thus,decrease its speed. In this thesis, a plasma actuator is tested in three supersonic rarefied flows (N1(M2-8Pa), N2(M4-8Pa) and N3(M4-71Pa)) and a hypersonic one (M20-0.062Pa), all generated by the wind tunnelMARHy.The plasma actuator induces flow modifications over the studied model, such as a change in the shock waveshape and an increase in the shock wave angle. In order to better understand the phenomena governingthese modifications, Pitot pressure, surface and gas temperature, electron data and spectroscopicmeasurements were analyzed. The results shown that two types of effects are involved: thermal (bulk andsurface) and ionization. Moreover, it was demonstrated that these effects had not the same importancedepending on the flow conditions.The plasma actuator was also modified in order to improve it. In particular, two types of generators wereused to biase the cathode: DC and pulsed. Finally, it was shown that, for a discharge power of 80 W, a 13%increase in the drag force could be expected and thus, a decrease in the heat load over the model body ofmore than 25%. Therefore, plasma actuators seem to be promising applications for space missions andatmospheric entries.

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