Дисертації з теми "Electrode electrolyte composite"
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Morana, Roberto. "The influence of particle type and process conditions on electrodeposited composite coatings." Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/8045.
Повний текст джерелаYin, Yijing. "An Experimental Study on PEO Polymer Electrolyte Based All-Solid-State Supercapacitor." Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/440.
Повний текст джерелаBodén, Andreas. "The anode and the electrolyte in the MCFC." Doctoral thesis, KTH, Kemiteknik, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4382.
Повний текст джерелаEtt av den svenska regeringens mål är att öka användandet av förnyelsebara bränslen och bränslen från biomassa. Bränsleceller och framförallt MCFC är användbara för dessa typer av bränslen. Den svenska marknaden kan dra fördelar av MCFC på två sätt; ökad bränsleutnyttjandegrad och utnyttjande av producerad värme för fjärrvärme. De flesta kommersiella MCFC-systemen idag är optimerade för användning av metan. Möjligheten att använda biomassa på den svenska marknaden gör det viktigt att studera hur MCFC kan anpassas eller optimeras för bra prestanda och låg degradering för användning med gas från biomassa eller andra förnyelsebara bränslen. Fokus i denna avhandling är på metoder som kan användas för att undersöka och utvärdera MCFC-elektroder och -elektrolyter med förnyelsebara bränslen, dvs. gaser innehållande CO2. Metoderna och resultaten är både experimentella och matematiskt modellerade. Målet med denna avhandling är att bättre förstå hur anodens prestanda beror på användningen av olika bränslen. Anodens kinetik och vattengasskiftreaktionen har studerats liksom möjligheten att förlänga cellens livstid genom att öka den initiala mängden elektrolyt medelst användning av anoden som reservoar. Effekten av segregation av katjoner i elektrolyten under last har också undersökts. Om gassammansättningen är i jämvikt enligt vattengasskiftreaktionen vid inloppet till strömtilledaren kommer gassammansättningen att vara nära uniform inuti elektroden. Om ingående gas inte är i jämvikt kommer stora koncentrationsgradienter uppkomma i strömtilledaren och påverka gassammansättningen i elektroden. Omsättningen med avseende på vattenskiftreaktionen av gasen i flödeskanalen verkar vara beroende av gasens flödeshastighet. För en anod som används i en uppfuktad blandning av vätgas och koldioxid som inte är i jämvikt befanns det att Ni har en viss löslighet i (Li/Na)2CO3. För att kunna använda anoden som reservoar för elektrolyt för att förlänga livstiden för MCFC skall anodens porstorleksfördelning överensstämma med katodens och ha en bimodal porstorleksfördelning för att ge en tillräckligt god prestanda i ett så stort elektrolytfyllnadsgradsintervall som möjligt. Modelleringsresultat för segregering av katjoner i elektrolyten under drift visar att litiumjoner anrikas i anoden för båda typerna av elektrolyt som används i MCFC. Elektrolytkoncentrationsförändringarna är små men kan behövas tas i beaktande vid långa driftstider. Denna avhandlings resultat kan användas för att bättre förstå hur MCFC skall anpassas för drift med förnyelsebara bränslen och hur elektroder kan utformas för att förlänga livstiden.
QC 20100630
Токарева, Е. С., та E. S. Tokareva. "Получение и функциональные свойства сложнооксидных материалов на основе Ca3Co4O9+δ как перспективных катодов для среднетемпературных ТОТЭ : магистерская диссертация". Master's thesis, б. и, 2021. http://hdl.handle.net/10995/99985.
Повний текст джерелаThe object of study in this work is a cathode material based on the Сa3Co4O9+δ. The aim of the work is to study the electrochemical behavior of electrodes based on the Сa3Co4O9+δ with the electrolyte materials BaCe0.5Zr0.3Y0.1Yb0.1O3- and BaCe0.7Zr0.1Y0.1Yb0.1O3-. The synthesis of the Сa3Co4O9+δ, Ca3Co4-xCuxO9 (х = 0.05; 0.1; 0.15; 0.2), BaCe0.5Zr0.3Y0.1Yb0.1O3-δ and BaCe0.7Zr0.1Y0.1Yb0.1O3- complex oxides was carried out by pyrolysis of citrate-salt compositions. Using a complex of modern research methods, phase, structural and microstructural attestation of the Сa3Co4O9+δ, Ca3Co4-xCuxO9 (х = 0.05; 0.1; 0.15; 0.2), BaCe0.5Zr0.3Y0.1Yb0.1O3-δ and BaCe0.7Zr0.1Y0.1Yb0.1O3- oxides were carried out. The thermal stability of the Сa3Co4O9+δ in air and in the argon atmosphere was studied by the thermo gravimetrical method. The thermal expansion of the Сa3Co4O9+δ and BaCe0.5Zr0.3Y0.1Yb0.1O3-δ oxides was studied by dilatometry, and their thermal compatibility was proved. The chemical compatibility of the Сa3Co4O9+δ oxide with the electrolyte materials Ba2In1.8W0.2O5.15, 0.7Ba2In2O5·0.3Ba2InNbO6, Ba3Ca1.18Nb1.82O9 δ, BaCe0.5Zr0.3Y0.1Yb0.1O3-δ, Lа0.6Sr0.4MnO3-δ and LaNi0.6Fe0.4О3-δ collector materials was studied, the optimal temperature of the cathode material Сa3Co4O9+δ annealing to the BaCe0.5Zr0.3Y0.1Yb0.1O3-δ electrolyte was established. The temperature dependences of the electrical conductivity of the Сa3Co4O9+δ and BaCe0.5Zr0.3Y0.1Yb0.1O3-δ in air were investigated. Electrodes based on composites with different mass contents of Сa3Co4O9+δ and BaCe0.5Zr0.3Y0.1Yb0.1O3-δ on substrates of BaCe0.5Zr0.3Y0.1Yb0.1O3-δ, as well as electrodes based on Ca3Co4-xCuxO9 (х = 0; 0.05; 0.1; 0.15) on substrates of BaCe0.7Zr0.1Y0.1Yb0.1O3 were formed. The polarization characteristics of the obtained electrodes, including those with an La0.6Sr0.4MnO3-δ+2 wt.% CuO oxide collector, were studied by the method of impedance spectroscopy on the symmetric cells.
Inaba, Minoru. "Electrochemical Reactions on Polymer Electrolyte Membrane/Electrode Composites." Kyoto University, 1994. http://hdl.handle.net/2433/74664.
Повний текст джерелаCaldeira, Vincent. "Développement d'électrodes composites architecturées à base de zinc pour accumulateurs alcalins rechargeables." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI065.
Повний текст джерелаThe work presented in this document results from a multidisciplinary study, the unique goal of which is to develop a negative electrode for alkaline rechargeable batteries. At the origin of this thesis, is the surprising discovery by EASYL of a new way to synthesize calcium zincate (CAZN), an electrochemically active material known for its good cycling characteristics in alkaline batteries. The advantage of such a discovery resides in its unique characteristics: the ultra-fast synthesis is carried out continuously, uses neither heating system nor alkaline solutions, yields pure and tailored CAZN crystals; it is therefore compatible with an industrial production of this material.Its use in a 4 Ah prismatic batteries allowed to unveil a core-shell operation mechanism, in which the electrode evolves towards an active zinc-core surrounded by a protective shell. So, if the nominal capacity remains below the theoretical one, the core of the electrode can be kept active while the surface is maintained, thus avoiding (or at least slowing down) possible dendrite formation and yielding prolonged cycle life.However, the use of calcium zincate as the only active material source is not appropriate, because the formation of the zinc-core leads to the appearance of a resistive layer of calcium hydroxide at its periphery, which reduces the overall electrochemical performance. As surprising as it may seem, it is possible to regenerate an electrode having formed such a calcium hydroxide-rich layer by a simple rest such as a stop of the battery. Nevertheless, it is preferable to avoid the formation of this resistive layer and to do so, the use of a mixture of sacrificial zinc oxide combined with calcium zincate has proven very effective, both from a morphological and an electrochemical point-of-view.However, the controlled formation of a zinc-rich core leads to zinc densification on itself; this decreases the surface of contact between the active material and the electrolyte, and thus the electrochemical performance. This negative effect has been overcome by drastically rethinking the structure of the electrode, in order to allow the formation of multiple and tailored zinc cores. To that goal, multilayers of current collector were employed, which proved simple and effective to reach high-performance and high cyclability zinc electrodes for alkaline batteries
Anderson, Jordan. "Electrochemical Studies of Nanoscale Composite Materials as Electrodes in Direct Alcohol Fuel Cells." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5104.
Повний текст джерелаPh.D.
Doctorate
Chemistry
Sciences
Chemistry
Tihli, Mustapha. "Relations entre electrosorption et insertion electrochimique dans les carbones : application au stockage d'energie electrique." Reims, 1987. http://www.theses.fr/1987REIMS008.
Повний текст джерелаEngstrom, Allison Michelle. "Vanadium Oxide Electrochemical Capacitors| An Investigation into Aqueous Capacitive Degradation, Alternate Electrolyte-Solvent Systems, Whole Cell Performance and Graphene Oxide Composite Electrodes." Thesis, University of California, Berkeley, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3616666.
Повний текст джерелаVanadium oxide has emerged as a potential electrochemical capacitor material due to its attractive pseudocapacitive performance; however, it is known to suffer from capacitive degradation upon sustained cycling. In this work, the electrochemical cycling behavior of anodically electrodeposited vanadium oxide films with various surface treatments in aqueous solutions is investigated at different pH. Quantitative compositional analysis and morphological studies provide additional insight into the mechanism responsible for capacitive degradation. Furthermore, the capacitance and impedance behavior of vanadium oxide electrochemical capacitor electrodes is compared for both aqueous and nonaqueous electrolyte-solvent systems. Alkali metal chloride and bromide electrolytes were studied in aqueous systems, and nonaqueous systems containing alkali metal bromides were studied in polar aprotic propylene carbonate (PC) or dimethyl sulfoxide (DMSO) solvents. The preferred aqueous and nonaqueous systems identified in the half-cell studies were utilized in symmetric vanadium oxide whole-cells. An aqueous system utilizing a 3.0 M NaCl electrolyte at pH 3.0 exhibited an excellent 96% capacitance retention over 3000 cycles at 10 mV s-1. An equivalent system tested at 500 mV s-1 displayed an increase in capacitance over the first several thousands of cycles, and eventually stabilized over 50,000 cycles. Electrodes cycled in nonaqueous 1.0 M LiBr in PC exhibited mostly non-capacitive charge-storage, and electrodes cycled in LiBr-DMSO exhibited a gradual capacitive decay over 10,000 cycles at 500 mV s-1. Morphological and compositional analyses, as well as electrochemical impedance modeling, provide additional insight into the cause of the cycing behavior. Lastly, reduced graphene oxide and vanadium oxide nanowire composites have been successfully synthesized using electrophoretic deposition for electrochemical capacitor electrodes. The composite material was found to perform with a higher capacitance than electrodes containing only vanadium oxide nanowires by a factor of 4.0 at 10 mV s-1 and 7.5 at 500 mV s-1. The thermally reduced composite material was examined in both symmetric and asymmetric whole cell electrochemical capacitor devices, and although the asymmetric cell achieved both higher energy and power density, the symmetric cell retained a higher capacitance over 50,000 cycles at 200 mV s-1.
Barchasz, Céline. "Développement d'accumulateurs Li/S." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00681504.
Повний текст джерелаSubbaraman, Ramachandran. "A multi-scale hierarchical approach for understanding the structure of the polymer electrolyte membrane fuel cell (PEMFC) electrodes - from nanoparticales to composites." online version, 2008. http://rave.ohiolink.edu/etdc/view.cgi?acc%5Fnum=case1205852564.
Повний текст джерелаSubbaraman, Ramachandran. "A MULTI-SCALE HIERARCHICAL APPROACH FOR UNDERSTANDING THE STRUCTURE OF THE POLYMER ELECTROLYTE MEMBRANE FUEL CELL (PEMFC) ELECTRODES - FROM NANOPARTICLES TO COMPOSITES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1205852564.
Повний текст джерелаBoulenouar-Mohamedi, Fatma Zohra. "Étude de l'oxydation anodique de l'hydrogène à l'interface métal/zircone stabilisée à haute température (métal=platine, nickel, cuivre)." Grenoble INPG, 1995. http://www.theses.fr/1995INPG0055.
Повний текст джерелаCAPRONI, ERICA. "Eletrolitos sólidos cerâmicos a base de óxido de zircônio para a detecção de oxigênio." reponame:Repositório Institucional do IPEN, 2007. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11534.
Повний текст джерелаMade available in DSpace on 2014-10-09T13:59:04Z (GMT). No. of bitstreams: 0
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
FAPESP:03/07331-0
Géniès, Sylvie. "Étude de la passivation de l'électrode carbone-lithium." Grenoble INPG, 1998. http://www.theses.fr/1998INPG0008.
Повний текст джерелаWoo, Sahng Hyuck. "Membranes composites acide perfluorosulfonique (PFSA)/argile pour un fonctionnement à faible humidité relative et haute température des piles à combustible à membrane échangeuse de protons (PEMFC)." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEM033.
Повний текст джерелаThis thesis introduces novel electrolyte membranes which can be operated at low relative humidity (below 50%) and intermediate temperature, i.e., 90℃. More specifically, the thesis takes benefit from hygroscopicity of microfibrous SEP (sepiolite) and tubular HNT (halloysite). Changes in Nafion membrane properties with blending time were studied. Moreover, these nanoclays are functionalized and pretreated to make them proton conductive and to improve their compatibility with short-side-chain PFSA (perfluorosulfonic acid) composite membranes based on Aquivion. To begin with, functionalized and pretreated clay nanoparticles are characterized prior to incorporation in polymer matrix: ATR-FTIR (attenuated total reflection-fourier transform infrared spectroscopy), Py-GC/MS (pyrolysis gas chromatography mass spectrometry), and TGA (thermogravimetric analysis). Composites membranes have them been prepared and characterized for proton conductivity, water uptake, swelling, thermo-mechanical strength and chemical stability. The dispersion state of SEP and HNT inside polymer phase was observed using SEM/EDS (field emission scanning electron microscopy/Energy dispersive X-ray spectroscopy). The properties of pretreated nanoclays are characterized using XRD (X-ray diffraction) and EDS. Chemical stability regarding radical attack against composite membranes is clarified using Ion meter through fluoride ion (F-) analysis. Proton conductivity of composite membranes is also measured under condition of different relative humidity and temperature. Following this, it is demonstrated by DMA (dynamic mechanical analysis) results that the particular elongated morphology of SEPs and HNTs participates to improving mechanical property of the composite membranes with decreased swelling ratio. MEAs (membrane electrode assembly) performance are evaluated to understand the advantage of the presence of nanoclays in the composite membranes regarding the relative humidity of the feeding gas, the operating temperature of the cell, and the hydrogen crossover. Detailed abstracts including main results were provided at the beginning of each chapter
Adami, Fatos. "Analyse infra-rouge in-situ de l'interface electrode metallique/solution par la methode mirftirs : mise au point et application de la technique a l'etude de l'electropolymerisation des phenols sur electrode de fer." Paris 7, 1987. http://www.theses.fr/1987PA077042.
Повний текст джерелаCaproni, Érica. "Estudo de eletrólitos sólidos cerâmicos à base de óxido de zircônio para a detecção de oxigênio." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-30032012-101612/.
Повний текст джерелаTaking advantage of the high thermal shock resistance of zirconia-magnesia ceramics and the high oxide ion conductivity of zirconia-yttria ceramics, composites of these ceramics were prepared by mixing, pressing and sintering different relative concentrations of ZrO2: 8.6 mol% MgO and ZrO2: 3mol% Y2O3 solid electrolytes. Microstructural analysis of the composites was carried out by X-ray diffraction and scanning electron microscopy analyses. The thermal behavior was studied by dilatometric analysis. The electrical behavior was evaluated by the impedance spectroscopy technique. An experimental setup was designed for measurement the electrical signal generated as a function of the amount of oxygen at high temperatures. The main results show that these composites are partially stabilized (monoclinic, cubic and tetragonal) and the thermal behavior is similar to that of ZrO2: 8.6 mol% MgO materials used in disposable high temperature oxygen sensors. Moreover, the results of analysis of impedance spectroscopy show that the electrical conductivity of zirconia:magnesia is improved with zirconia-yttria addition and that the electrical signal depends on the amount of oxygen at 1000 °C, showing that the ceramic composites can be used in oxygen sensors.
Fichou, Denis. "L'interface oxyde de zinc/électrolyte : étude des processus primaires." Paris 6, 1986. http://www.theses.fr/1986PA066259.
Повний текст джерелаSar, Jaroslaw. "Interfaces et durabilité d'électrodes avancées pour l'énergie : IT-SOFC et SOEC Coral Microstructure of Graded CGO/LSCF Oxygen Electrode by Electrostatic Spray Deposition for Energy (IT-SOFC, SOEC) Electrochemical properties of graded and homogeneous Ce0.9Gd0.1O2-δ-La0.6Sr0.4Co0.2Fe0.8O3-δ composite electrodes for intermediate-temperature solid oxide fuel cells Three dimensional analysis of Ce0.9Gd0.1O1.95–La0.6Sr0.4Co0.2Fe0.8O3−δ oxygen electrode for solid oxide cells Mechanical behavior of Ce0.9Gd0.1O1.95-La0.6Sr0.4Co0.2Fe0.8O3−δ oxygen electrode with a coral microstructure for solid oxide fuel cell and solid oxide electrolyzer cell Durability test on coral Ce0.9Gd0.1O2-δ-La0.6Sr0.4Co0.2Fe0.8O3-δ with La0.6Sr0.4Co0.2Fe0.8O3-δ current collector working in SOFC and SOEC modes". Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI106.
Повний текст джерелаInterfaces and durability of advanced electrodes for energy (IT-SOFC and SOEC)The objective of this PhD thesis is to fabricate advanced oxygen electrode based on Ce0.9Gd0.1O1.95 (CGO) and La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) with graded and homogeneous composition onto yttria-stabilized zirconia (YSZ = 8 mol. % Y2O3-doped ZrO2) electrolyte using electrostatic spray deposition. A thin and dense layer of CGO was inserted between LSCF and YSZ to serve as a barrier diffusion layer. The novel microstructure with high porosity and large surface area is expected to improve the electrochemical performances. The electrical behavior of the electrode was investigated by impedance spectroscopy versus temperature in air. A detailed microstructural description was performed by 3D reconstructed model from FIB-SEM and X-ray nanotomography and related to electrical properties. The mechanical analysis was performed by scratch and ultramicroindentation tests. Finally, durability tests were performed on the electrode with 45 cm2 oxygen active area, up to 800 h at around 770°C, in full cell SOFC and SOEC configurations operating respectively in H2 and H2/ H2O mixture
Malki, Abdelhafid. "Transformation électrocatalytique de produits issus de la biomasse : oxydation du fructose sur électrodes d'or et de platine." Poitiers, 1988. http://www.theses.fr/1988POIT2274.
Повний текст джерелаForano, Claude. "Les conducteurs protoniques : HSbO3.nH2O ET SnO2.nH2O : caracterisation, etude rmn et applications." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF21069.
Повний текст джерелаWENG, HU-CHENG, and 翁瑚珹. "Supercapacitance of Polyaniline/Mesoporous Carbon Composite Electrode in C6H4(OH)2/H2SO4 Electrolyte." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6jn5hk.
Повний текст джерела國立勤益科技大學
化工與材料工程系
107
In this study, carbon mesoporous material, CMK-3, was adopted as supporting material for electroactive polymerspolyaniline (PANI), polyaniline, for supercapacitor application. Where hydroquinone (HQ) was also integrated to enhance the redox reaction of PANI. The results show that the addition of PANI improves the capacitance of electrode from 101 F/g (CMK-3) to 480 F/g (PANI/CMK-3), the addition of HQ furtherly improves the capacitance to 684 F/g (PANI/CMK-3/HQ). In-situ analyses including cyclic voltammetry (CV), chronopotentiometry (CP), electron impedance spectrum (EIS) analyses were applied for electrode performance examination. For materials characterization, the crystal structure, morphology, microstructure, and porosity were examined by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM), and 77K N2 adsorption/desorption analyses, respectively. The effects of PANI polymerization time, HQ concentration, and PANI/CMK-3 ratio on capacitance were discussed. The research results of this thesis can be summarized as follows:(i)The PANI provides higher energy density and also acts as binder of the electrode;(ii) The CMK-3 provides higher electron double layer capacitance EDLC and stabilize the polyaniline by its highly porosity;(iii)With the addition of HQ, the capacitance of PANI/CMK-3 was further enhanced.The durability was also studied by long-term operation test. The results show that PANI/CMK-3/HQ with great potential for supercapacitor application. Finally, the potential of PANI/CMK-3/HQ based supercapacitor was successfully demonstrated.
Wen, Chih-yu, and 溫治宇. "Study of supercapacitor fabricated with composite electrodes and gel polymer electrolyte." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/nc72b5.
Повний текст джерела國立中山大學
電機工程學系研究所
106
This study separately mixed Ni(CH3COO)2 and H2O4W solutions with mesocarbon microbeads (MCMBs), filtered the resulting solution, and then subjected the carbon paste to heat treatments to give rise to composite carbon powder. The powder was then mixed with an adhesive and then applied to a conductive carbon (CC)/ITO glass substrate, which completed the fabrication of a composite electrode for supercapacitors. Gel polymer electrolytes (GPEs) were made using lithium salts LiClO4 and LiBOB in propylene carbonate (PC) solvent. The resulting electrolytes were tested using AC impedance spectroscopy and galvanostatic charge-discharge efficiency tests to determine the influence of the lithium salt used on the capacitance properties of the GPE. Finally, charge-discharge efficiency tests, ambient temperature tests, and lifetime tests were conducted on the supercapacitor. The results show that a 0.75-M H2O4W solution paired with a 100C heat treatment to produce a composite-structured carbon powder in addition to 25 wt.% carbon black and 2 wt.% adhesive results in a composite electrode with the best capacitance properties. Its specific capacitance in a electrolyte (1 M LiClO4) was 249 F∙g-1. The GPE (Sample 4) made with 8 wt.% LiClO4 and 30 wt.% Ionic liquid (IL) presented lower bulk impedance, lower electrolyte-electrode interface impedance, a lower device decline rate, and a higher specific capacitance. The charge-discharge tests revealed that within the voltage range of 0 V to 2.5 V and a charge/discharge current density of 0.3 A∙g-1, the WO3/MCMB presented the optimal specific capacitance of 234.22 F∙g-1. From this results, It could be calculated that the energy density was 293 Wh∙kg-1, and the power density was 105.4 kW∙kg-1 (discharge current @0.03 A). The results therefore demonstrate that the composite electrode fabricated in this study exist good performance capacitance. Furthermore, the composite electrode presented near-100% charge-discharge efficiency and good adhesion between the electrode materials and the substrate after 1,000 charge-discharge cycles in the galvanostatic charge-discharge efficiency tests and service-life tests.
CAO, MENG SIAN, and 曹孟賢. "The study of electrolyte for GNS/CNT composites applied to supercapcaitor electrode." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/71031097506603495008.
Повний текст джерела國立雲林科技大學
化學工程與材料工程系
103
Supercapacitor is a high efficiency energy storage element, the performance is between traditional capacitor and chemical capacitor. Electrode material and electrolyte is the factor influence performance. Electrode materials mainly include carbon materials, metal oxides and conductive polymer material. Carbon material is widely used due to electrochemical stability and low prices. Graphene and carbon nanotubes both contain good conductive, and KOH is the neutral alkalinity electrolyte that largely applied in supercapacitor. Therefore in this report, we choose LiPF6/EC/DMC organic electrolyte to compare the electrochemical performance of electrode. We use scanning electron microscope(SEM), Cyclic voltammetry (CV), AC impedance(EIS) to analysis characterization and test . The results indicate the capacity and the energy density of KOH solution electrolyte and LiPF6/EC/DMC organic electrolyte at cooling rate condition 110℃/min are 110.3 F/g、15.32 wh/kg and 48.32F/g、101.225wh/kg respectively. The best parameters of oxygen plasma is 100W and 45 minute. The capacity of two capacity is 181.32 F/g and 80.98F/g respectively, its increase 64.38% (KOH) and 69.35% (LiPF6/EC/DMC)
Huang, Kuan-Chieh, and 黃冠傑. "On the Composite Counter Electrodes and Quasi-Solid-State Electrolytes for Dye-Sensitized Solar Cells." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/29598026080233046186.
Повний текст джерела國立臺灣大學
化學工程學研究所
100
The exploration of solar energy is one of most intensive studies on the technologies of green energy in recent years. A new generation of solar cell, dye-sensitized solar cell (DSSC), has been investigated worldwide due to the advantages, including facile development of cell, flexibility, and colorful appearance. In terms of (1) improving the power-conversion efficiency (η) of cell (Chapter 3), (2) reducing the consumption of fabrication of cell (Chapter 4 and Chapter 5), and (3) enhancing the long-term durability of cell (Chapter 6 and Chapter 7), various nanomaterials have been synthesized and prepared for the counter electrodes (CEs) and the electrolytes of the DSSCs in this dissertation. For improving the η of DSSC, a conducting glass substrate spin-coated with a composite thin film, consisting of platinum nanoparticles (PtNPs) and multi-wall carbon nanotubes (MWCNTs), is prepared for a CE of a DSSC (Chapter 3). A homemade polymer, poly(oxyethylene)-segmented imide (POEM), is used and served as stabilizer and dispersant for MWCNTs in the aqueous solution. The best electro-catalytic ability of the film for the reduction of tri-iodide (I3-) ions is obtained after the film is annealed at 390 oC. This is attributed to the complete decomposition of non-conducting POEM, to the formation of PtNP with a moderate crystalline size, and to the surface roughness of film. Thus, an η of 8.47 ± 0.21% of the DSSC with the CE based on the composite film shows much higher than that of a DSSC applying a Pt-coated CE (η = 7.41 ± 0.24%) under illumination of 100 mW cm-2. For reducing the consumption of fabrication of DSSC, an electro-polymerized composite thin film consisting of nanographites (NGs) and polyaniline (PANI) on the conducting glass substrate is prepared for the replacement of costly Pt as the CE of a DSSC (Chapter 4). A well dispersing ability of NG/aniline particles in the depositing solution is obtained after the particles are treated by reflux-condensation; thereby improving the depositing quality of NG/PANI composite film on the substrate by electro-polymerization. The fine distribution of NGs in the film results in an enhanced conductivity of it, with reference to the conductivity of pristine PANI film. Thus, a percentage of 98.3%, corresponding to the η of a DSSC made of Pt-coated CE, for the DSSC with the NG/PANI CE is acquired. The competitive electro-catalytic ability of the film in comparison to that of film of Pt is confirmed by scanning electrochemical microscopy. In addition, hollow spherical PANI (hsPANI) particles are also deposited on the conducting glass substrate by means of reflux-condensation and electro-polymerization for the CE of a DSSC (Chapter 5). A larger active surface area (A) of thin film consisting of hsPANI particles is estimated to be 0.191 cm2, with reference to that of pristine PANI film (A = 0.126 cm2) by rotating disk electrode. The increased A is beneficial for the reduction of I3-. Thus, a percentage of 95.4%, corresponding to the η of a DSSC with a Pt-coated CE, for the DSSC made of hsPANI CE is obtained. The film consisting of hsPANI particles can serve as a potential alternative for the replacement of Pt catalyst on the CE. For enhancing the long-term durability of DSSC, a liquid electrolyte based on organic solvent is converted into a quasi-solid-state electrolyte by the gelation using a polymer, poly(vinyidene fluoride-co-hexafluoro propylene) (PVDF-HFP), for a DSSC (Chapter 6). The crystallinity of PVDF-HFP decreases when high thermal stable nanoparticles of aluminum nitride (AlN) are incorporated in the quasi-solid-state electrolyte. Thus, the diffusion coefficient of iodide (I-) is increased from 2.97 × 10-6 to 3.52 × 10-6 cm2 s-1. Under 1 sun illumination, the η of a DSSC with this quasi-solid-state electrolyte gives a higher value of 5.27 ± 0.23%, compared to that of a DSSC without adding AlN in its electrolyte (η = 4.75 ± 0.08%). Merely a loss of 5% in η of the DSSC with reference to its initial η is observed for the at-rest durability of the quasi-solid-state DSSC in a period of 1,000 h. In addition, a solvent-free ionic liquid (IL)-based electrolyte containing a synthesized composite of MWCNT/crown ether is prepared for a quasi-solid-state DSSC (Chapter 7). An IL, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF4), is used. Prior to the characterization of performance for the DSSC with this IL electrolyte, crown ether, 15-crown-5, is preferably chosen owning to its appropriate size of cavity for capturing the lithium (Li+) in the electrolyte in comparison to the capturing abilities of 12-crown-4 and 18-crown-6. Thus, the decrease in electrostatic force between Li+ and I- leads to an improvement of the exchange reaction of I- and I3- by adding the MWCNT/15-crown-5 composite in the EMIBF4 electrolyte. The transport of electrons is facilitated by MWCNTs. Consequently, the values of short-circuit current density and η of the DSSC with both MWCNT/15-crown-5 and EMIBF4 in its electrolyte exhibits increases by 71.2 and 38.8%, respectively, with reference to these values of a DSSC with a bare EMIBF4. The at-rest durability of this quasi-solid-state DSSC is found to be unfailing for a period of 1,200 h.
Huang, Yao-Ting, and 黃耀霆. "Preparation of Embedded Multifunctional Energy Storage Composites with Activated Carbon Fiber Electrode and PVdF-based Gel Polymer Electrolytes ¬— on Electrochemical and Mechanical Properties." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2efhp8.
Повний текст джерела國立臺灣大學
工程科學及海洋工程學研究所
107
This study demonstrates a standardized process to fabricate embedded multifunctional energy storage composites. Using Activated carbon fiber electrodes and PVdF-based gel electrolyte as building materials for supercapacitors. Two-step packaging method is used to fabricate glass-fiber reinforced polymer (GFRP) composites that can make it simultaneously bear mechanical loadings and store energy. Carbon fabric with three different activation methods and PVdF-based gel electrolyte are characterized by an electrochemical test. In addition, the electrochemical properties of the multifunctional energy storage composites are determined by galvanostatic charge-discharge (GCD), cyclic voltammetry and AC impedance method (EIS). The result shows that specific capacitance and energy density of supercapacitor with GFRP have 142 mF/g and 15.7 Wkg^(-1) provide 20% and 30% enhancement performance than a bare cell, respectively. The mechanical properties of the supercapacitor embedding of GFRP are investigated by tensile test; the result shows the average stress of 350.1 MPa and Young’s modulus of 14 GPa. Furthermore, to understand the electrical properties of multifunctional energy storage composites with external load changes, two different situations were also established. With the tensile load increase, the supercapacitor energy density is increased by around 10%, and the structural supercapacitor undergoing cyclic tensile is still functioning normally before the GFRP failure load.