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1

YANG, YONGRUI. "Flexible Supercapacitors with Novel Gel Electrolytes". University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1590682495188219.

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2

Zhang, Ruirong. "A study of flexible supercapacitors : design, manufacture and testing". Thesis, Brunel University, 2016. http://bura.brunel.ac.uk/handle/2438/13426.

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Supercapacitors have attracted great attention because of their high power density, long life cycle and high efficiency. They can be generally classified into two types: electrical double-layer capacitors (EDLCs) and pseudocapacitors. Compared with pseudocapacitors, EDLCs have a very fast charge/discharge rate, higher power density, higher coulombic efficiency and longer cycle life. Recently, in order to meet the requirements of portable and wearable electronics, supercapacitor development is moving towards flexible and stretchable solutions. This thesis presents the design, fabrication, performance testing and optimisation of flexible strip and fibre EDLCs. In this research, a sandwich structured strip EDLC was designed and manufactured. Experimental design was utilised to optimise the operation parameters of the EDLC in order to improve its capacity for energy storage. The flexibility of the strip EDLCs was studied extensively by mechanical tests under static and dynamic loading conditions, and the correlation between the electrochemical performance of the EDLCs and the mechanical testing process was investigated. Novel coaxial fibre EDLCs have also been studied and developed in this study. Fibre supercapacitors showed a good flexibility and weavability. The activated carbon produced by ball-milling method with optimum specific capacitance was mixed with commercial ink to produce active material to optimise the electrochemical performance of fibre EDLCs. The flexible EDLCs were applied into different appliances to demonstrate the stability of performance and the usability of EDLCs developed in this study. The electrical current and potential range can be altered by connecting multiple strip or fibre EDLCs in parallel or in series to meet the power and energy requirements. It has been proved that the flexible EDLCs developed have a great potential to be used as energy storage devices for smart electronics. This thesis makes original contributions to knowledge, including using an advanced test method to study the electrochemical performance of flexible supercapacitors under static and dynamic mechanical testing, investigation of the effect of key parameters in the manufacturing process on the performance of strip supercapacitors using experimental design method to optimise the supercapacitors’ performance, and optimisation of the performance of fibre supercapacitors by improving the structure and using a new active material with higher specific capacitance.
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Lorenzo, Fernandez Marta. "Flexible supercapacitors utilising the multifunctional rôle of ionic liquids". Thesis, Queen's University Belfast, 2018. https://pure.qub.ac.uk/portal/en/theses/flexible-supercapacitors-utilising-the-multifunctional-role-of-ionic-liquids(8645dbf6-5a8e-4f19-ba27-bbb6adb7c7e3).html.

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The study on flexible, ultrathin and safe energy storage devices such as supercapacitors or batteries is an emerging area to “power-up” the next-generation of portable and flexible electronics such as mobile phones, computers, displays, wearable and implantable biomedical devices. In general, a supercapacitor is composed of two electrodes, electrolyte, separator and current collectors and it can store and deliver charge at relatively high rates. The challenge to design such supercapacitors to be flexible lies in the development of flexible electrodes and leak-proof electrolytes, as well as, the retention of the electrochemical characteristics of high power density, long cycle life and high efficiency under considerable physical deformation. An innovative one-pot synthesis to fabricate electronically conducting polymer-biopolymer composites films such as polypyrrole-cellulose composites that are intrinsically conducting and flexible is presented. The method consisted of an in situ polymerisation of pyrrole in a solution of cellulose in the ionic liquid, 1-butyl-3-methylimidazolium chloride. The resulting polypyrrole-cellulose composite film was chemically blended, and it showed flexible polymer properties while retaining the electronic properties of the polypyrrole. Addition of a hydrophobic ionic liquid, trihexyl(tetradecyl)phosphonium bis{(trifluoromethyl) sulfonyl}amide and graphite powder enhanced the flexibility and conductivity of the composite films, respectively. The composites films obtained were applied as electrodes in flexible supercapacitors using a simple scalable method to design flexible, ultrathin and safe supercapacitors. Three devices were fabricated, (i) electrical double-layer supercapacitors, (ii) electrochemical supercapacitors and (iii) hybrid supercapacitors. The multifunctional rôle of ionic liquids as solvent, electrolyte and plasticiser was exploited to fabricate these novel flexible supercapacitors which showed an excellent cycle life of 15000 cycles with nearly 100 % of capacitance retention, an operational voltage between 1.6 V and 3.2 V and a maximum energy and power density of 0.008 μW h cm-2 and 1.78 μW cm-2, respectively. Moreover, the design nature of these electrodes, chemical stability and feasibility to use biocompatible components will enable the fabrication of task-specific flexible supercapacitors with durable cycle life and chemical stability.
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4

ZACCAGNINI, PIETRO. "Graphene-based supercapacitors for flexible and harsh environments application". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2875757.

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5

Areir, Milad. "Development of 3D printed flexible supercapacitors : design, manufacturing, and testing". Thesis, Brunel University, 2018. http://bura.brunel.ac.uk/handle/2438/16659.

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The development of energy storage devices has represented a significant technological challenge for the past few years. Electrochemical double-layer capacitors (EDLCs), also named as supercapacitors, are a likely competitor for alternative energy storage because of their low-cost, high power density, and high fast charge/discharge rate. The recent development of EDLCs requires them to be lightweight and flexible. There are many fabrication techniques used to manufacture flexible EDLCs, and these methods can include pre-treatment to ensure more efficient penetration of activated carbon (AC) patterns onto the substrate, or those that utilise masks for the definitions of patterns on substrates. However, these methods are inconvenient for building cost-effective devices. Therefore, it was necessary to find a suitable process to reduce the steps of manufacture and to be able to print multiple materials uniformly. This research work describes the first use of a 3D printing technology to produce flexible EDLCs for energy storage. In this research work, the four essential elements for the EDLCs substrate, current collector, activated electrode, and gel electrolyte were investigated. The AC powder was milled by ball milling to optimise the paste deposition and the electrochemical performance. A flexible composite EDLC was designed and manufactured by 3D printing. The electrochemical performance of the flexible composite EDLCs was then examined. Being highly flexible is one of the critical demands for the recent development of EDLCs. Therefore, highly flexible EDLCs were designed and manufactured by only one single extrusion process. The 3D highly flexible EDLC maintains significant electrochemical performance under a mechanical bending test. To meet the power and energy requirements, the EDLCs were connected and tested in series and parallel circuits. A supercapacitor based on printed AC material displays an area specific capacitance of 1.48 F/cm2 at the scan rate of 20 mV/s. The coulombic efficiency for the flexible EDLC was found to be 59.91%, and the cycling stability was achieved to be 56% after 500 cycles. These findings indicate that 3D printing technology may be increasingly used to develop more sophisticated flexible wearable electronic devices.
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6

Si, Wenping. "Designing Electrochemical Energy Storage Microdevices: Li-Ion Batteries and Flexible Supercapacitors". Doctoral thesis, Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-160049.

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Die Menschheit steht vor der großen Herausforderung der Energieversorgung des 21. Jahrhundert. Nirgendwo ist diese noch dringlicher geworden als im Bereich der Energiespeicherung und Umwandlung. Konventionelle Energie kommt hauptsächlich aus fossilen Brennstoffen, die auf der Erde nur begrenzt vorhanden sind, und hat zu einer starken Belastung der Umwelt geführt. Zusätzlich nimmt der Energieverbrauch weiter zu, insbesondere durch die rasante Verbreitung von Fahrzeugen und verschiedener Kundenelektronik wie PCs und Mobiltelefone. Alternative Energiequellen sollten vor einer Energiekrise entwickelt werden. Die Gewinnung erneuerbarer Energie aus Sonne und Wind sind auf jeden Fall sehr wichtig, aber diese Energien sind oft nicht gleichmäßig und andauernd vorhanden. Energiespeichervorrichtungen sind daher von großer Bedeutung, weil sie für eine Stabilisierung der umgewandelten Energie sorgen. Darüber hinaus ist es eine enttäuschende Tatsache, dass der Akku eines Smartphones jeglichen Herstellers heute gerade einen Tag lang ausreicht, und die Nutzer einen zusätzlichen Akku zur Hand haben müssen. Die tragbare Elektronik benötigt dringend Hochleistungsenergiespeicher mit höherer Energiedichte. Der erste Teil der vorliegenden Arbeit beinhaltet Lithium-Ionen-Batterien unter Verwendung von einzelnen aufgerollten Siliziumstrukturen als Anoden, die durch nanotechnologische Methoden hergestellt werden. Eine Lab-on-Chip-Plattform wird für die Untersuchung der elektrochemischen Kinetik, der elektrischen Eigenschaften und die von dem Lithium verursachten strukturellen Veränderungen von einzelnen Siliziumrohrchen als Anoden in einer Lithium-Ionen-Batterie vorgestellt. In dem zweiten Teil wird ein neues Design und die Herstellung von flexiblen on-Chip, Festkörper Mikrosuperkondensatoren auf Basis von MnOx/Au-Multischichten vorgestellt, die mit aktueller Mikroelektronik kompatibel sind. Der Mikrosuperkondensator erzielt eine maximale Energiedichte von 1,75 mW h cm-3 und eine maximale Leistungsdichte von 3,44 W cm-3. Weiterhin wird ein flexibler und faserartig verwebter Superkondensator mit einem Cu-Draht als Substrat vorgestellt. Diese Dissertation wurde im Rahmen des Forschungsprojekts GRK 1215 "Rolled-up Nanotechnologie für on-Chip Energiespeicherung" 2010-2013, finanziell unterstützt von der International Research Training Group (IRTG), und dem PAKT Projekt "Elektrochemische Energiespeicherung in autonomen Systemen, no. 49004401" 2013-2014, angefertigt. Das Ziel der Projekte war die Entwicklung von fortschrittlichen Energiespeichermaterialien für die nächste Generation von Akkus und von flexiblen Superkondensatoren, um das Problem der Energiespeicherung zu addressieren. Hier bedanke ich mich sehr, dass IRTG mir die Möglichkeit angebotet hat, die Forschung in Deutschland stattzufinden
Human beings are facing the grand energy challenge in the 21st century. Nowhere has this become more urgent than in the area of energy storage and conversion. Conventional energy is based on fossil fuels which are limited on the earth, and has caused extensive environmental pollutions. Additionally, the consumptions of energy are still increasing, especially with the rapid proliferation of vehicles and various consumer electronics like PCs and cell phones. We cannot rely on the earth’s limited legacy forever. Alternative energy resources should be developed before an energy crisis. The developments of renewable conversion energy from solar and wind are very important but these energies are often not even and continuous. Therefore, energy storage devices are of significant importance since they are the one stabilizing the converted energy. In addition, it is a disappointing fact that nowadays a smart phone, no matter of which brand, runs out of power in one day, and users have to carry an extra mobile power pack. Portable electronics demands urgently high-performance energy storage devices with higher energy density. The first part of this work involves lithium-ion micro-batteries utilizing single silicon rolled-up tubes as anodes, which are fabricated by the rolled-up nanotechnology approach. A lab-on-chip electrochemical device platform is presented for probing the electrochemical kinetics, electrical properties and lithium-driven structural changes of a single silicon rolled-up tube as an anode in lithium ion batteries. The second part introduces the new design and fabrication of on chip, all solid-state and flexible micro-supercapacitors based on MnOx/Au multilayers, which are compatible with current microelectronics. The micro-supercapacitor exhibits a maximum energy density of 1.75 mW h cm-3 and a maximum power density of 3.44 W cm-3. Furthermore, a flexible and weavable fiber-like supercapacitor is also demonstrated using Cu wire as substrate. This dissertation was written based on the research project supported by the International Research Training Group (IRTG) GRK 1215 "Rolled-up nanotech for on-chip energy storage" from the year 2010 to 2013 and PAKT project "Electrochemical energy storage in autonomous systems, no. 49004401" from 2013 to 2014. The aim of the projects was to design advanced energy storage materials for next-generation rechargeable batteries and flexible supercapacitors in order to address the energy issue. Here, I am deeply indebted to IRTG for giving me an opportunity to carry out the research project in Germany. September 2014, IFW Dresden, Germany Wenping Si
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7

Zhang, Panpan, Faxing Wang, Sheng Yang, Gang Wang, Minghao Yu e Xinliang Feng. "Flexible in-plane micro-supercapacitors: Progresses and challenges in fabrication and applications". Elsevier, 2020. https://tud.qucosa.de/id/qucosa%3A74431.

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The great popularity of portable, wearable, and implantable smart electronics has intensively boosted the development of flexible miniaturized power supplies. Owing to the fast charge/discharge capability, high power delivery, long cycling lifetime, easy fabrication and integration, flexible in-plane micro-supercapacitors (FPMSCs) are of significance as the micropower sources for the next-generation flexible on-chip electronics. In this review, we provide a comprehensive overview about FPMSCs and discuss the recent advances in their fabrication and applications. Particular emphasis is put on the emergent device fabrication technologies of FPMSCs, including deposition techniques, coating strategies, etching methods, and printing technologies. Moreover, we highlight the unique applications of FPMSCs in constructing smart responses and self-powered integrated systems in terms of multifunctional operation modes. Finally, the remaining challenges regarding flexibility, performance improvement, smart response, and microdevice integration of FPMSCs are discussed, which will stimulate further research in this thriving field.
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8

Wu, Zhenkun. "Metal-reduced graphene oxide for supercapacitors and alternating current line-filters". Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53941.

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We design a facile approach to investigate the role benzene derivatives play in the capacitance enhancement of graphene-based supercapacitors. The main reason is attributed to the pseudocapacitance of the aromatic molecules rather than the former one. Meanwhile, we find that the para and ortho substituted benzene derivatives contribute much more than the meta substituted ones. In addition, we fabricate an all-solid-state flexible MSC based on metal-reduced GO. The as-fabricated MSC shows high areal capacitance and excellent reliability, which makes it a promising energy storage candidate for wearable electronics. Based on the work of MSC, we achieve a flexible ac line-filter that is not only competitive against commercial product but also suitable for mass production. Meanwhile, we produce a three-dimensional graphene/polydimethylsiloxane composite that gives a thermal resistance as small as 14 mm2K/W, which is comparable to commercial products. What’s more, a convenient transient program that saves much time is developed to measure the thermal resistance.
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9

Zhang, Panpan, Feng Zhu, Faxing Wang, Jinhui Wang, Renhao Dong, Xiaodong Zhuang, Oliver G. Schmidt e Xinliang Feng. "Stimulus-Responsive Micro-Supercapacitors with Ultrahigh Energy Density and Reversible Electrochromic Window". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235489.

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10

Li, Hongyan, Yang Hou, Faxing Wang, Martin R. Lohe, Xiaodong Zhuang, Li Niu e Xinliang Feng. "Flexible All-Solid-State Supercapacitors with High Volumetric Capacitances Boosted by Solution Processable MXene and Electrochemically Exfoliated Graphene". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235446.

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11

Yang, Muxuan. "Molecular Engineering of Polyaniline with Polydopamine and Graphene for All-Solid-State Flexible Micro-Supercapacitors". University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron1626872581300145.

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12

De, Silva Gardiyawasam L. Thushani Thilanjani. "ALL SOLID-STATE FLEXIBLE SUPERCAPACITORS WITH VERTICALLY ALIGNED MULTIWALLED CARBON NANOTUBES (MWCNT) SYNTHESIZED DIRECTLY ON METAL FOIL". OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2588.

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This work is mainly focused on the investigation on all solid-sate flexible supercapacitors using MWCNT directly grown on Inconel foil. Detail physical characterization of the as grown MWCNTs were performed using Scanning Electron Microscopy (SEM), Raman and Specific surface area measurement (SSA). SSA evaluated using volumetric adsorption isotherm measurements show that such MWCNTs have effective surface area of ~ 30m2/g. These as grown MWCNT on metals foils were used to fabricate the Electrochemical Double Layer Capacitors (EDLC) or Supercapacitors. A poly(vinyl alcohol)/phosphoric acid (PVA/H3PO4) polymer gel has been used as both the electrolyte and the separator. The capacitors were fabricated by dipping the as synthesized Inconel stripes in PVA/H3PO4 gel polymer and then combining two such stripes together. Several electrochemical measurements such as Cyclic Voltammetry (CV), Galvanic Charge Discharge (GCD) cycling and Electrochemical Impedance Spectroscopy (EIS) were performed on multiple devices in order to establish these structures as viable energy storage systems. Key device parameters measured and analyzed along with standard electrochemical circuit modeling indicates that these devices have Specific Capacitances (CSP) in the mF range with a low internal resistance. The low internal resistance could be a consequence of growing the MWCNTs directly on metal foils. The highest areal capacitance measured was 19.6 mF/cm2 at 1mVs-1. The flexibility and robustness of the devices were tested by performing the aforementioned measurements at different bending angles. Our measurements indicate that these devices can withstand a large number of such bending cycles (~ 2000) without losing any functionality. It was however observed that these capacitors sustain physical damage for bending cycles > 2000 cycles and loose ~50% of their capacitance values. A detailed energy density and power density analysis confirmed that the performance of these devices is in the rage of Supercapacitors. The device parameters can be further improved by thermal annealing of the as grown electrodes in air. A summary of the comparison with other work is also presented.
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13

Yang, Xiangwen, Zhixing Lin, Jingxu Zheng, Yingjuan Huang, Bin Chen, Yiyong Mai e Xinliang Feng. "Facile template-free synthesis of vertically aligned polypyrrole nanosheets on nickel foams for flexible all-solid-state asymmetric supercapacitors". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-224947.

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This paper reports a novel and remarkably facile approach towards vertically aligned nanosheets on three-dimensional (3D) Ni foams. Conducting polypyrrole (PPy) sheets were grown on Ni foam through the volatilization of the environmentally friendly solvent from an ethanol–water solution of pyrrole (Py), followed by the polymerization of the coated Py in ammonium persulfate (APS) solution. The PPy-decorated Ni foams and commercial activated carbon (AC) modified Ni foams were employed as the two electrodes for the assembly of flexible all-solid-state asymmetric supercapacitors. The sheet-like structure of PPy and the macroporous feature of the Ni foam, which render large electrode–electrolyte interfaces, resulted in good capacitive performance of the supercapacitors. Moreover, a high energy density of ca. 14 Wh kg−1 and a high power density of 6.2 kW kg−1 were achieved for the all-solid-state asymmetric supercapacitors due to the wide cell voltage window.
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Yang, Xiangwen, Zhixing Lin, Jingxu Zheng, Yingjuan Huang, Bin Chen, Yiyong Mai e Xinliang Feng. "Facile template-free synthesis of vertically aligned polypyrrole nanosheets on nickel foams for flexible all-solid-state asymmetric supercapacitors". Royal Society of Chemistry, 2016. https://tud.qucosa.de/id/qucosa%3A30332.

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This paper reports a novel and remarkably facile approach towards vertically aligned nanosheets on three-dimensional (3D) Ni foams. Conducting polypyrrole (PPy) sheets were grown on Ni foam through the volatilization of the environmentally friendly solvent from an ethanol–water solution of pyrrole (Py), followed by the polymerization of the coated Py in ammonium persulfate (APS) solution. The PPy-decorated Ni foams and commercial activated carbon (AC) modified Ni foams were employed as the two electrodes for the assembly of flexible all-solid-state asymmetric supercapacitors. The sheet-like structure of PPy and the macroporous feature of the Ni foam, which render large electrode–electrolyte interfaces, resulted in good capacitive performance of the supercapacitors. Moreover, a high energy density of ca. 14 Wh kg−1 and a high power density of 6.2 kW kg−1 were achieved for the all-solid-state asymmetric supercapacitors due to the wide cell voltage window.
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15

Si, Wenping [Verfasser], Oliver G. [Akademischer Betreuer] Schmidt, Oliver G. [Gutachter] Schmidt e Yongfeng [Gutachter] Mei. "Designing Electrochemical Energy Storage Microdevices: Li-Ion Batteries and Flexible Supercapacitors / Wenping Si ; Gutachter: Oliver G. Schmidt, Yongfeng Mei ; Betreuer: Oliver G. Schmidt". Chemnitz : Universitätsbibliothek Chemnitz, 2015. http://d-nb.info/1214303390/34.

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16

Guemiza, Hazar. "Electrodes à base d'oxyde de graphène réduit - Polymères (liquides ioniques) pour des supercondensateurs performants". Electronic Thesis or Diss., CY Cergy Paris Université, 2024. http://www.theses.fr/2024CYUN1293.

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Ces travaux de thèse visent à développer des supercondensateurs flexibles tout solide pour les utiliser dans le cadre de l'énergie comme matériaux d’électrode de supercondensateurs. Pour ce faire, l’oxyde de graphène réduit a été choisi comme matériaux d’électrode et associer à différents poly(liquide ioniques) (PIL) dans des composites rGO-PIL. La première partie de cette étude se concentre sur l'élaboration d'électrodes rGO-PIL à l'aide d'électrolytes conventionnels (EMImTFSI). Les mesures électrochimiques montrent que la présence de 10 wt% de PIL augmente la capacité à 80 F.g-1. La deuxième partie de cette étude se concentre sur le développement de SCs tout solide. Ainsi, des PILs et une nouvelle famille de polyélectrolytes obtenus par la coaservation PIL de charges opposées, nommé gels ioniques dynamiques (DIGs), ont été mises au point. Ce type de DIGs peut être un candidat potentiel en tant qu'électrolyte tout solide, ainsi qu'en tant qu'agent intercalant ionique/polymérique pour les matériaux 2D en couches, assurant une continuité conductrice à travers le dispositif. L'élaboration d'électrodes rGO-PIL, rGO-DIG et leur association avec des électrolytes PIL et DIG ont été élaborés. Les meilleures performances ont été obtenues en utilisant le DIGs comme électrolyte. Le supercondensateur élaboré peut fonctionner efficacement à des températures supérieures à 80°C (28 F.g-1) avec une forte augmentation de la capacité spécifique par rapport aux valeurs à température ambiante (10 F.g-1) et sans risque de fuite du liquide ionique, ce qui n'est pas couramment le cas avec les électrolytes conventionnels. Enfin, les supercondensateurs ont été fabriqués sur des collecteurs de courants flexibles et différentes mesures de flexibilité ont été élaborées. Tous ces électrolytes solides peuvent opérer à une fenêtre de potentiel élevée (2 V). Ce travail a aussi démontré un grand potentiel d’utilisation des électrolytes tout solides, sans risque de fuite même à hautes températures
This thesis aims to develop flexible all-solid-state supercapacitors (SCs) for energy storage systems. For this purpose, reduced graphene oxide was selected to be used as an active material and associated with different poly(ionic liquid) (PIL) in rGO-PIL composites. The first part of this study focuses on the elaboration of rGO-PIL electrodes using conventional liquid electrolytes. Electrochemical measurements show that the presence of 10% of PIL enhances the capacitance to 80 F.g-1. The second part of this study focuses on the development of solid-state SCs. Hence PILs and a new family of polyelectrolytes obtained via the complex conservation of oppositely charged PILs called Dynamic Ion Gels was developed. Such DIGs can be a potential candidate as a safe and solid-state electrolyte as well as an ionic/polymeric intercalant agent for layered 2D materials., ensuring highly conducting continuity through the hole device. The elaboration of rGO-PIL, rGO-DIG electrodes and their association with PIL and DIGs electrolyte was elaborated. The best performances were obtained when using DIGs as electrolyte. The fabricated cell can efficiently operate at high temperatures above 80°C (28 F.g-1) with the strong enhancement of specific capacitance compared to the values at room temperature (10 F.g-1) and without any risk of liquid leakage which is not commonly obtained with conventional solvent. All these solid electrolytes can operate at an elevated potential window (2 V). Finally, the supercapacitors were made on flexible current collectors and different bending measurements were elaborated at elevated temperatures. This work demonstrated the great potential of using solid-state electrolytes which ensures safety and good performance at elevated temperatures
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17

RAFIQUE, AMJID. "Flexible Fiber-Shaped Supercapacitor for Wearable Electronics". Doctoral thesis, Politecnico di Torino, 2019. http://hdl.handle.net/11583/2729354.

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Chivers, Benjamin William. "Development of Novel PEDOT:PSS Fabrication Techniques for High Performance, Flexible RFID Antennas and Energy Storage Devices". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20155.

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Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been widely studied as either nanometre-scale, transparent films or a conductive, capacitive composite material in electronic devices. While significant effort has been directed towards increasing PEDOT:PSS conductivity in transparent films, very little nanoscale, morphological consideration has been applied to micron-scale PEDOT:PSS materials. As a result, PEDOT:PSS conductivity often decreases in micron-scale materials, and the polymer has been largely overlooked as a high performance material in practical applications. In this thesis, PEDOT:PSS fabrication techniques are optimised to produce high conductivity and high electrochemical performance micron-scale quantities of PEDOT:PSS. The optimised PEDOT:PSS is used to fabricate an RFID antenna with extraordinary radiation efficiency, a high efficiency zinc/bromine flow battery anode, and an ultra-high performance composite-fibre-supercapacitor. A novel fabrication technique was developed to maintain PEDOT:PSS electrical and electrochemical performance in micron-scale applications. By submersion in ethylene glycol, PEDOT:PSS phase separation, conformational changes, stability and PEDOT loading were optimised for a commercially available PEDOT:PSS. Polymer films 40 m thick were reliably produced with over 500 S cm-1. The high performance PEDOT:PSS was fabricated into a 2.45 GHz RFID dipole antenna, achieving 99.7% peak radiation efficiency, a novel result for a non-metal antenna. The same morphologically considerate approach was applied to zinc/bromine flow battery anode design, more than doubling peak charge density. Energy density increased by over 50%, and charge efficiency increased by 9.3%, directly increasing battery efficiency. PEDOT:PSS was composited with reduced graphene oxide to produce a symmetric fibre supercapacitor with very high capacitance, 138 F cm-3 compared to 55 F cm-3 and 14 F cm-3 for PEDOT:PSS and rGO respectively.
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19

Cakici, Murat. "Highly flexible carbon fibre fabric based nanostructured hybrids for high performance energy storage systems". Thesis, The University of Sydney, 2017. http://hdl.handle.net/2123/18123.

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Electrochemical supercapacitors (ES), or ultracapacitors, store energy using either reversible adsorption of electrolyte ions (electrochemical double layer capacitors) or fast surface redox reactions on its electrodes (pseuodocapacitors). Currently, they are used together with batteries or fuel cells when high-power delivery or uptake is required. They have exceptional features such as high power density, high cycle efficiency, fast charging-discharging rate, long lifecycle, and safe operation. Therefore, they have attracted tremendous interest as next generation energy conversion and storage systems, ranging from portable wearable electronics to hybrid electric vehicles. However, low energy density is the main drawback to use ES as a stand-alone energy storage system. Thus, their performance should be improved to fulfil the requirements of ever-growing energy demands of progressing global economy and industry. In addition, most of the ES electrodes are fabricated from powders which makes them unsuitable for their potential use as wearable lightweight flexible devices in the future. Considering the requirements of future industrial applications of ES, this thesis focuses on synthesizing high performance, flexible, mechanically stable, lightweight, eco-friendly, and low cost ES electrodes using green, scalable, and inexpensive fabrication methods. To develop highly efficient electrode materials suitable for practical applications in a flexible design, novel synthesis procedures were explored to incorporate pseudocapacitive materials (metal oxides and electrically conductive polymers) into three-dimensional and flexible conductive carbon materials to obtain multicomponent hybrid materials. Therefore, hybrid materials reported in this thesis are binder-/conductive agent-free and also have enhanced three-dimensional nanostructures which promote energy storage. Simplicity of the fabrication methods also enable large scale and economical production of flexible and mechanically stable materials which can be directly used as ES electrodes. First, electrode materials with a unique nanostructure was developed for supercapacitor applications based on carbon fibre fabric (CFF) / MnO2 hybrid materials, in which MnO2 was uniformly coated on the surface of CFF. A green hydrothermal method was used to functionalize CFF with coral-like MnO2 nanostructures to improve the electrochemical performance of the hybrid composites. The morphological, structural, and crystalline properties of composites were analysed by using various techniques to confirm the deposition of coral-like MnO2 on CFF. The electrochemical performance was examined in a three-electrode system and cyclic voltammetry results reveal the superior specific capacitance of 467 F g-1 at a scan rate of 5 mV s-1. The cycling performance test revealed that the capacitance retention was 99.7% and the coulombic efficiency remained as high as 99.3% after 5000 cycles, demonstrating an outstanding electrochemical stability of the coral-like MnO2/CFF composite electrode. Second, synthesis method used in the first study was optimised to obtain three novel nanostructured MnO2 layers on flexible CFF substrates. It was observed that different morphologies of MnO2 could be grown on carbon fibres by adjusting the concentration of precursor solution. The morphological, structural, and crystalline properties of the composites were analysed by using various techniques to confirm that MnO2 nanostructures were successfully anchored on CFF. The electrochemical performances of the nanostructured MnO2/CFF composites were examined in two-electrode symmetric cell configuration in 1 M Na2SO4 electrolyte. Among three different morphologies, nanoplate type MnO2/CFF electrode had the best electrochemical performance (528 F g-1 at 0.5 A g-1 current density). In addition, binder and conductive agent free, flexible MnO2/CFF composite electrode had excellent cycling stability and coulombic efficiency. Finally, activated CFF (ACFF) / reduced graphene oxide (RGO)/polyaniline (PANI) composite flexible electrodes were prepared by in-situ polymerization method. Polymerization of aniline was optimized by adjusting aniline concentration to obtain PANI nanowire arrays on the three-dimensional flexible carbon based substrate. Electrochemical performance of ACFF/RGO/PANI composite was compared with ACFF and ACFF/RGO electrodes in two-electrode symmetrical cell configuration in 1 M H2SO4 electrolyte. The results indicated that ACFF/RGO/PANI exhibited outstanding area normalized capacitance due to synergistic effect between ACFF, RGO, and PANI. The facile synthesis method of the composite electrode using textile based substrate enables the possibility for fabrication of high-performance flexible energy storage devices.
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20

Coustan, Laura. "Matériaux pseudo-capacitifs pour supercondensateurs flexibles". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS169/document.

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Les supercondensateurs sont des dispositifs de stockage de l'énergie électrique particulièrement intéressants pour les applications de puissance. Les rendre flexibles permet de considérer de nouvelles possibilités d'intégration. Néanmoins, l'optimisation de la densité d'énergie, point faible de ces dispositifs, passe par la recherche et l'étude de nouveaux matériaux d'électrode et d'électrolytes. Dans ce but, ce travail de thèse s'est orienté vers des matériaux pseudo-capacitifs, avec l'utilisation d'électrodes à base de MnO2, et d'électrolytes à base de liquide ionique fonctionnalisé de type biredox. Afin de conserver le caractère flexible des électrodes, le dioxyde de manganèse a d'abord été synthétisé pour la formulation d'encres à pulvériser sur substrat flexible. A cette occasion, l'influence de dispersants sur les performances a été étudiée. Les performances de matériaux nanocomposites à base de fibres de carbone et de graphène décorés par MnO2 ont ensuite été évaluées. Les contributions faradiques et surfaciques à la capacité développée par MnO2 ont ensuite été déterminées par une étude électrochimique fine. Enfin, l'étude d'un nouveau liquide ionique fonctionnalisé utilisé dans un dispositif carbone/carbone a confirmé l'attractivité de ces phénomènes faradiques dans les performances électrochimiques d'un supercondensateur
Supercapacitors are attractive electrical energy storage devices for power applications. As flexible devices new integration opportunities can be consider. Nevertheless, the optimization of the energy density, weak point of these devices, proceeds through the search and the study of new electrode materials and electrolytes. In this aim, this thesis work is turned towards so called pseudo-capacitive materials, with the use of MnO2-based electrodes, and biredox Ionic Liquid electrolytes. To preserve the flexible behavior of the electrodes, the manganese dioxide was, at first, synthesized for the formulation of an ink to be sprayed on flexible substrates. The influence of dispersing agents on the electrochemical performances was evaluated. Performances of nanocomposite materials prepared with carbon nanofibers and graphene oxide sheets were also studied. Faradaic and surface contributions to the capacity developed by MnO2 electrode material were then determined by an advanced electrochemical study. Finally, the study of a new Ionic Liquid used in a symmetrical carbon/carbon supercapacitor confirmed the attractiveness of these Faradaic phenomena for the enhancement of the supercapacitor electrochemical performances
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21

Pal, Ramendra K. "Fabrication of flexible, biofunctional architectures from silk proteins". VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4995.

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Advances in the biomedical field require functional materials and processes that can lead to devices that are biocompatible, and biodegradable while maintaining high performance and mechanical conformability. In this context, a current shift in focus is towards natural polymers as not only the structural but also functional components of such devices. This poses material-specific functionalization and fabrication related questions in the design and fabrication of such systems. Silk protein biopolymers from the silkworm show tremendous promise in this regard due to intrinsic properties: mechanical performance, optical transparency, biocompatibility, biodegradability, processability, and the ability to entrap and stabilize biomolecules. The unique ensemble of properties indicates opportunities to employ this material into numerous biomedical applications. However, specific processing, functionalization, and fabrication techniques are required to make a successful transition from the silk cocoon to silk-based devices. This research is focused on these challenges to form silk-based functional material and devices for application in areas of therapeutics, bio-optics, and bioelectronics. To make silk proteins mechanically conformable to biological tissues, the first exploration is directed towards the realization of precisely micro-patterned silk proteins in flexible formats. The optical properties of silk proteins are investigated by showing the angle-dependent iridescent behavior of micropatterned proteins, and developing soft micro-optical devices for light concentration and focusing. The optical characteristics and fabrication process reported in the work can lead to the future application of silk proteins in flexible optics and electronics. The microfabrication process of silk proteins is further extended to form shape-defined silk protein microparticles. Here, the specificity of shape and the ability to form monodisperse shapes can be used as shape encoded efficient cargo and contrast agents. Also, these particles can efficiently entrap and stabilize biomolecules for drug delivery and bioimaging applications. Next, a smart confluence of silk sericin and a synthetic functional polymer PEDOT:PSS is shown. The composite materials obtained have synergistic effects from both polymers. Silk proteins impart biodegradability and patternability, while the intrinsically conductive PEDOT:PSS imparts electrical conductivity and electrochemical activity. Conductive micro architectures on rigid as well as flexible formats are shown via a green, water-based fabrication process. The applications of the composite are successfully demonstrated by realizing biosensing and energy storage devices on rigid or flexible forms. The versatility of the approach will lead to the development of a variety of applications such as in bio-optics, bioelectronics, and in the fundamental study of cellular bio electrogenic environments. Finally, to expand the applicability of reported functional polymers and composites beyond the microscale, a method for silk nano-patterning via electron beam lithography is explored. The technique enables one-step fabrication of user defined structures at the submicron and nano-scales. By virtue of acrylate chemistry, a very low energetic beam and dosage are required to form silk nano-architectures. Also, the process can form both positive and negative features depending on the dosage. The fabrication platform can also form nano scale patterns of the conductive composite. The conductive measurements confirm the formation of conductive nanowires and the ability of silk sericin to entrap PEDOT:PSS particles in nanoscale features.
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22

MIGLIORINI, LORENZO. "DEVELOPMENT OF FUNCTIONAL NANOCOMPOSITE MATERIALS TOWARDS BIODEGRADABLE SOFT ROBOTICS AND FLEXIBLE ELECTRONICS". Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/704286.

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World population is continuously growing, as well as the influence we have on the ecosystem’s natural equilibrium. Moreover, such growth is not homogeneous and it results in an overall increase of older people. Humanity’s activity, growth and aging leads to many challenging issues to address: among them, there are the spread of suddenly and/or chronic diseases, malnutrition, resource pressure and environmental pollution. Research in the novel field of biodegradable soft robotics and electronics can help dealing with these issues. In fact, to face the aging of the population, it is necessary an improvement in rehabilitation technologies, physiological and continuous monitoring, as well as personalized care and therapy. Also in the agricultural sector, an accurate and efficient direct measure of the plants health conditions would be of help especially in the less-developed countries. But since living beings, such as humans and plants, are constituted by soft tissues that continuously change their size and shapes, today’s traditional technologies, based on rigid materials, may not be able to provide an efficient interaction necessary to satisfy these needs: the mechanical mismatch is too prohibitive. Instead, soft robotic systems and devices can be designed to combine active functionalities with soft mechanical properties that can allow them to efficiently and safely interact with soft living tissues. Soft implantable biomedical devices, smart rehabilitation devices and compliant sensors for plants are all applications that can be achieved with soft technologies. The development of sophisticated autonomous soft systems needs the integration on a unique soft body or platform of many functionalities (such as mechanical actuation, energy harvesting, storage and delivery, sensing capabilities). A great research interest is recently arising on this topic, but yet not so many groups are focusing their efforts in the use of natural-derived and biodegradable raw materials. In fact, resource pressure and environmental pollution are becoming more and more critical problems. It should be completely avoided the use of in exhaustion, pollutant, toxic and non-degradable resources, such as lithium, petroleum derivatives, halogenated compounds and organic solvents. So-obtained biodegradable soft systems and devices could then be manufactured in high number and deployed in the environment to fulfil their duties without the need to recover them, since they can safely degrade in the environment. The aim of the current Ph.D. project is the use of natural-derived and biodegradable polymers and substances as building blocks for the development of smart composite materials that could operate as functional elements in a soft robotic system or device. Soft mechanical properties and electronic/ionic conductive properties are here combined together within smart nanocomposite materials. The use of supersonic cluster beam deposition (SCBD) technique enabled the fabrication of cluster-assembled Au electrodes that can partially penetrate into the surface of soft materials, providing an efficient solution to the challenge of coupling conductive metallic layers and soft deformable polymeric substrates. In this work, cellulose derivatives and poly(3-hydroxybutyrate) bioplastic are used as building blocks for the development of both underwater and in-air soft electromechanical actuators that are characterized and tested. A cellulosic matrix is blended with natural-derived ionic liquids to design and manufacture completely biodegradable supercapacitors, extremely interesting energy storage devices. Lastly, ultrathin Au electrodes are here deposited on biodegradable cellulose acetate sheets, in order to develop transparent flexible electronics as well as bidirectional resistive-type strain sensors. The results obtained in this work can be regarded as a preliminary study towards the realization of full natural-derived and biodegradable soft robotic and electronic systems and devices.
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23

Brousse, Kevin. "Intégration de micro-supercondensateurs à hautes performances sur puce de silicium et substrats flexibles". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30090/document.

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Le développement de l'internet des objets au service des " Smart Cities " requière des sources d'énergie miniaturisées. Ces travaux concernent la préparation de micro- supercondensateurs à hautes performances par voies sèches. Des films minces de carbure de titane ont été déposés sur wafer de silicium par pulvérisation, puis convertis par chloration partielle en films de carbone dérivé de carbure microporeux adhérents. 205 mF.cm-2 / 410 F.cm-3 ont été délivrés en milieu 1M H2SO4, et 170 F.cm-3 dans un mélange de liquide ionique et d'acétonitrile en contrôlant la taille des micropores. Les micro-supercondensateurs préparés sur wafer par cette voie, compatible avec les techniques de microfabrication utilisées dans l'industrie des semi-conducteurs, surpassent les performances des micro-supercondensateurs sur puce rapportées jusqu'alors. Enfin, l'écriture laser d'oxydes commerciaux sur polyimide s'est avérée prometteuse pour la préparation de micro-supercondensateurs flexibles
The development of the internet of things, serving the concept of Smart Cities, demands miniaturized energy storage devices. Electrochemical double layer capacitors (or so called EDLCs) are a good candidate as they can handle fast charge and discharge over 1,000,000 cycles. This work focuses on the preparation of high performance micro- supercapacitors using non wet processing routes. Titanium carbide (TiC) thin films were first deposited on silicon wafer by non-reactive DC magnetron sputtering. The deposition parameters, such as pressure and temperature, were optimized to prepare dense and thick TiC films. Then, microporous carbide-derived carbon (CDC) films with sub-nanometer pore diameters were obtained by removing the metallic atoms of the TiC films under chlorine atmosphere. Partial chlorination led to strongly adherent TiC-CDC films which could be used as electrode in aqueous electrolyte. Capacitance values of 205 mF.cm-2 / 410 F.cm-3 were delivered in 1M H2SO4, and were stable over 10,000 cycles. In order to increase the energy density of the on-chip electrodes, the pore sizes were increased to accommodate the larger ions of organic electrolytes, by performing chlorination at higher temperatures. The 700°C chlorinated TiC-CDC electrodes delivered up to 72 mF.cm-2 within a 3 V potential window in an ionic liquid / acetonitrile mixture. Another strategy consisted in the grafting of anthraquinone (AQ) molecules, which brought additional faradic contribution to the capacitive current. Electrochemical grafting by pulsed chronoamperometry allowed to double the TiC-CDC capacitance in aqueous electrolyte (1M KOH). On-chip CDC-based micro-supercapacitors were successfully prepared via reactive ion etching/ inductive coupled plasma procedure followed by chlorination. This non-wet processing route is fully compatible with the microfabrication techniques used in the semi-conductor industry, and the as-prepared micro-devices outperforms the current state of art of on-chip micro-supercapacitors. Aside, the preparation of flexible micro-supercapacitors was achieved via direct laser-writing, which provided a facile and scalable engineering with low cost. Ruthenium oxide (RuO2)-based interdigitated electrodes were obtained from laser-writing of a commercial RuO2.xH2O / cellulose acetate mixture spin-coated onto KaptonTM. Capacitance values of ~30 mF.cm-2 were recorded in 1M H2SO4 for the flexible device. This work open the way for the design of high performance micro-devices at a large scale
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24

HUANG, ZIH-TING, e 黃子庭. "Enhancive Performance of Flexible Composite Supercapacitors". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/n9r3re.

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碩士
國立臺灣科技大學
化學工程系
106
Composite materials were synthesized by polyaniline, polypyrrole and carbon dots on cellulose-based substrates, independently. The materials at different weights were prepared by the in-situ polymerization method.   In the case of Polyaniline-series electrodes, the specific capacitance was maximum (174 F/g at a scan rate of 5mV/s) in 120μl of aniline monomer. Meanwhile, in the Polypyrrole-series film electrodes, the specific capacitance significantly decreased from 571 F/g at 5 mV/s of 240μl (pyrrole amounts) with decreasing content of pyrrole amounts. Although the specific capacitance of 180μl pyrrole amount electrode was lower than that of 240μl pyrrole amount electrode, the flexibility of 180μl pyrrole amount electrode was better than that of 240μl amount. These electrochemical results indicate that Polypyrrole-composites have better properties than PANi-series. Furthermore, the stability of polyaniline was 81% after 3000 cycles, but polypyrrole and Cdot-ppy were almost 100%.   Since two polymers above indicated the inferior charge/discharge profile, carbon dots as added into in-situ polymerization with pyrrole to enhance their specific capacitance. The addition of carbon dots on composite films consisting of polypyrrole showed superior electrochemical performance in comparison with the electrode without carbon dots. Incidentally, the specific capacitance was 1073 F/g for the composite film added 100μl carbon dots. This value is 1.9 times higher than that electrode without carbon dots. Moreover, these composites film also showed better charge/discharge shape than that without carbon dots. These results indicate that this composite can produce a flexible electrode for energy storage devices with high efficiency.
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25

Cheng, Tzu Yu, e 鄭茲瑀. "Preparation and Characterization of Graphene-based Electrodes for Flexible Supercapacitors". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/72618438426636264441.

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碩士
國立清華大學
化學工程學系
104
With the growing demand of the portable and wearable energy storage systems, the flexible supercapacitors have been received great attention. This study demonstrates that the flexible graphene nanosheets/carbon nanotube hybrid film (GS-SWCNT, GS-MWCNT) as electrode for supercapacitors and discusses the substrates (e.g. cellulose fibers and PTFE membrane) and preparation method (e.g. vacuum filtration and dip-drying) of hybrid film. The nanoarchitecture of carbon as active materials is important for energy storage. 8GS-2SWCNT exhibits much higher porosity and improves the electrical conductivities by using SWCNT as both the spacers and conductive linkers between individual graphene sheets, compared with bare graphene. Using cellulose fibers and vacuum filtration to support 8GS-2SWCNT (8GS-2SWCNT-cel(F)) which possesses 3D porous nanostructure due to the backbones of cellulose fibers and porous of carbon materials. The GS and SWCNT are strongly bound to cellulose fibers and fill the pores. This structure significantly enhances the specific surface area, improving both ionic and electronic transport kinetics. 8GS-2SWCNT-cel(F) exhibits the capacitive performance with a high specific capacitance of 127.2 F/g at 5 mV/s. Upon further decoration with MnO2 by chemical co-deposition, the MnO2/GS/SWCNT hybrid film (MnO2-8GS-2SWCNT-cel(F)) reaches a specific capacitance as high as 318.6 F/g at 5 mV/s, demonstrating the introduction of MnO2 is feasible to improve the capacitance performance. MnO2-8GS-2SWCNT-cel(F) also shows good flexibility and cycle stability (83.7 % after 5000 cycles) causes them as a promising electrode material for supercapacitor applications. The symmetric flexible supercapacitor prepared with MnO2-8GS-2SWCNT-cel(F) exhibits high energe density of 4.28 Wh/kg at a power density of 500 W/kg. Consequently, it is found that as-prepared hybrid film shows high specific capacitance, excellent rate capability, and good stability which is a promising potential application as an effective electrode material for supercapacitors.
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26

Si, Wenping. "Designing Electrochemical Energy Storage Microdevices: Li-Ion Batteries and Flexible Supercapacitors". Doctoral thesis, 2014. https://monarch.qucosa.de/id/qucosa%3A20191.

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Die Menschheit steht vor der großen Herausforderung der Energieversorgung des 21. Jahrhundert. Nirgendwo ist diese noch dringlicher geworden als im Bereich der Energiespeicherung und Umwandlung. Konventionelle Energie kommt hauptsächlich aus fossilen Brennstoffen, die auf der Erde nur begrenzt vorhanden sind, und hat zu einer starken Belastung der Umwelt geführt. Zusätzlich nimmt der Energieverbrauch weiter zu, insbesondere durch die rasante Verbreitung von Fahrzeugen und verschiedener Kundenelektronik wie PCs und Mobiltelefone. Alternative Energiequellen sollten vor einer Energiekrise entwickelt werden. Die Gewinnung erneuerbarer Energie aus Sonne und Wind sind auf jeden Fall sehr wichtig, aber diese Energien sind oft nicht gleichmäßig und andauernd vorhanden. Energiespeichervorrichtungen sind daher von großer Bedeutung, weil sie für eine Stabilisierung der umgewandelten Energie sorgen. Darüber hinaus ist es eine enttäuschende Tatsache, dass der Akku eines Smartphones jeglichen Herstellers heute gerade einen Tag lang ausreicht, und die Nutzer einen zusätzlichen Akku zur Hand haben müssen. Die tragbare Elektronik benötigt dringend Hochleistungsenergiespeicher mit höherer Energiedichte. Der erste Teil der vorliegenden Arbeit beinhaltet Lithium-Ionen-Batterien unter Verwendung von einzelnen aufgerollten Siliziumstrukturen als Anoden, die durch nanotechnologische Methoden hergestellt werden. Eine Lab-on-Chip-Plattform wird für die Untersuchung der elektrochemischen Kinetik, der elektrischen Eigenschaften und die von dem Lithium verursachten strukturellen Veränderungen von einzelnen Siliziumrohrchen als Anoden in einer Lithium-Ionen-Batterie vorgestellt. In dem zweiten Teil wird ein neues Design und die Herstellung von flexiblen on-Chip, Festkörper Mikrosuperkondensatoren auf Basis von MnOx/Au-Multischichten vorgestellt, die mit aktueller Mikroelektronik kompatibel sind. Der Mikrosuperkondensator erzielt eine maximale Energiedichte von 1,75 mW h cm-3 und eine maximale Leistungsdichte von 3,44 W cm-3. Weiterhin wird ein flexibler und faserartig verwebter Superkondensator mit einem Cu-Draht als Substrat vorgestellt. Diese Dissertation wurde im Rahmen des Forschungsprojekts GRK 1215 "Rolled-up Nanotechnologie für on-Chip Energiespeicherung" 2010-2013, finanziell unterstützt von der International Research Training Group (IRTG), und dem PAKT Projekt "Elektrochemische Energiespeicherung in autonomen Systemen, no. 49004401" 2013-2014, angefertigt. Das Ziel der Projekte war die Entwicklung von fortschrittlichen Energiespeichermaterialien für die nächste Generation von Akkus und von flexiblen Superkondensatoren, um das Problem der Energiespeicherung zu addressieren. Hier bedanke ich mich sehr, dass IRTG mir die Möglichkeit angebotet hat, die Forschung in Deutschland stattzufinden.
Human beings are facing the grand energy challenge in the 21st century. Nowhere has this become more urgent than in the area of energy storage and conversion. Conventional energy is based on fossil fuels which are limited on the earth, and has caused extensive environmental pollutions. Additionally, the consumptions of energy are still increasing, especially with the rapid proliferation of vehicles and various consumer electronics like PCs and cell phones. We cannot rely on the earth’s limited legacy forever. Alternative energy resources should be developed before an energy crisis. The developments of renewable conversion energy from solar and wind are very important but these energies are often not even and continuous. Therefore, energy storage devices are of significant importance since they are the one stabilizing the converted energy. In addition, it is a disappointing fact that nowadays a smart phone, no matter of which brand, runs out of power in one day, and users have to carry an extra mobile power pack. Portable electronics demands urgently high-performance energy storage devices with higher energy density. The first part of this work involves lithium-ion micro-batteries utilizing single silicon rolled-up tubes as anodes, which are fabricated by the rolled-up nanotechnology approach. A lab-on-chip electrochemical device platform is presented for probing the electrochemical kinetics, electrical properties and lithium-driven structural changes of a single silicon rolled-up tube as an anode in lithium ion batteries. The second part introduces the new design and fabrication of on chip, all solid-state and flexible micro-supercapacitors based on MnOx/Au multilayers, which are compatible with current microelectronics. The micro-supercapacitor exhibits a maximum energy density of 1.75 mW h cm-3 and a maximum power density of 3.44 W cm-3. Furthermore, a flexible and weavable fiber-like supercapacitor is also demonstrated using Cu wire as substrate. This dissertation was written based on the research project supported by the International Research Training Group (IRTG) GRK 1215 "Rolled-up nanotech for on-chip energy storage" from the year 2010 to 2013 and PAKT project "Electrochemical energy storage in autonomous systems, no. 49004401" from 2013 to 2014. The aim of the projects was to design advanced energy storage materials for next-generation rechargeable batteries and flexible supercapacitors in order to address the energy issue. Here, I am deeply indebted to IRTG for giving me an opportunity to carry out the research project in Germany. September 2014, IFW Dresden, Germany Wenping Si
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WEN, HE-CHUN, e 温賀淳. "Preparation and Characterization of Hydrous Ruthenium Oxide Solid State Flexible Supercapacitors". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/bqdt55.

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碩士
國立高雄科技大學
化學工程與材料工程系
107
In this study, ruthenium oxide (RuO2)-polyethylene terephthalate deposited with indium tin oxide (PET/ITO)|polyvinyl alcohol (PVA)/clay|RuO2 -(PET/ITO) flexible symmetry electrochemical supercapacitors were fabricated by using sandwich assembling technique, where RuO2-PET/ITO, cross-linked PVA/clay, and sodium sulphate acted as the electrode, the electrolyte composite membrane, and the electrolyte, respectively. RuO2-PET/ITO electrode was prepared by three-pole constant potential electrochemical deposition method, in which PET/ITO and antimony trichloride used as the substrate the plating solution. The structure of the sample was characterized by Field emission gun scanning electron microscope (FE-SEM), Thermogravimetric analysis (TGA) and Multi-function X-ray diffractometer (XRD) and X-ray photoelectron spectroscopy. Electrochemical properties were further carried out by means of potentiostat/Galvanostat and Leak current tester. Results showed that the hydrated RuO2 is tightly bonded to the surface of PET/ITO substrate. The specific capacitance (Csp) of RuO2 electrode increased with the increasing negative electrical potential. When the potential is -0.6 V, the RuO2 electrode has the highest value of Csp (141.63 F/g), as the scanning rate is 50 mV/s, the real part of resistance is 43.5 Ω. As RuO2 electrode is annealed at 100 °C, the value of Csp (315.61 F/g) is increased due to the rearrangement of the hydrated RuO2 atom. As for electrical property analysis, RuO2|PVA/clay |RuO2 flexible supercapacitor has a specific capacitance of 24.51 F/g, the impedance is 68.44 Ω, and the energy density and power density are 17.647 Wh/Kg and 80.211 kW/Kg. After 5000 cycles test, the capacitance retention rate of RuO2|PVA/clay |RuO2 flexible supercapacitor is still 89%, the real part of impedance is 68.44 Ω. After bending 100 times at 30° bending angle, the capacitance retention rate of RuO2|PVA/clay |RuO2 flexible supercapacitor is also still 91%.
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28

涂育誠. "The study of Bending Fatigue of the flexible Metal Additions/Graphene Supercapacitors". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/58494375244238777853.

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碩士
國立彰化師範大學
機電工程學系所
104
In this paper, several flexible metals/graphene Super-capacitors were fabricated using sol-gel methodology and their electric performance were characterized by the cyclic voltammetry measurement and the bending test. In our research, we used silver nitrate (AgNO3), nickel nitrate Ni (NO3)2, manganese nitrate and Mn (NO3)2‧6H2O as the additions. Each of them dissolved in deionized water (DI Water), and we also added some carbon blacks to enhance their conductivity. The silver additions presents the better performance than other two metals ones. We also experimented different angles by using the micro-tensile test tensile machine, discussing the performance of the electrochemistry double layer capacitance (EDLC) current-voltage relationship. Furthermore, using scanning electron microscope (SEM) we could observe the surface condition and the Specific Surface Area of our EDLC. Repeated bending test shows that the more metal additions that represent the higher electric performance to result that the resistance of bending is better. Manganese oxide is the best one to all additions. Above all, if we consider the electric performance only we could choose the silver addition, but if we consider the bending resistance only we could choose Manganese oxide to be the addition. As the results be they could be the guideline of selecting the better materials to fabricate the Super-capacitors.
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29

Tsai, Kun-Ju, e 蔡昆儒. "SWCNT/Ni-Co-Mn hydroxide nanohybrid materials as electrodes for flexible supercapacitors". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/8z5daq.

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30

Tsai, Sung-Ying, e 蔡松穎. "Preparation of the Porous Array Electrodes and Their Applications on Flexible Supercapacitors". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/r8tx53.

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碩士
國立虎尾科技大學
光電工程系光電與材料科技碩士班
104
The soft electronic era did come. Many lightweight flexible electronic devices such as the flexible panel display, flexible solar cell and the wearable electronics have been extensively studied. Thus, a highly efficient energy storage device was required for all of soft electronic devices. Supercapacitors are also known as electrical double-layer capacitors or ultracapacitors. The function of the supercapacitors is between the traditional capacitors and electrochemical cell, which also can be regarded as an ideal energy storage element. The advantages of supercapacitors including faster charge/discharge rate, high energy density, long lifetime, and low maintenance cost were the major advantages of supercapacitors which make them ideal candidates for energy storage. However, the energy storage performance of the supercapacitors is mainly affected by the electrode surface characteristics and the contact area between electrodes and electrolyte. Therefore, preparing of porous electrodes is reasonable to increase the storage effect of the supercapacitor. In this study, polystyrene (PS) microspheres were synthesized by dispersion polymerization technique first. Then, porous Polydimethylsiloxane (PDMS) array structure was fabricated by soft-lithography method. Later, a conducting layer was coated on the surface of porous array after the multi-walled carbon nanotube (MWCNT) and Graphene (G) mixture suspension pouring into the porous array. A H3PO4/PVA gel electrolyte was filled between two porous electrodes; a porous PDMS-based supercapacitor was assembled in a sandwich structure after a separator inserting. The specific capacitances, electrochemical analysis, cycle stability of the porous electrode supercapacitors were explored. This porous electrode-based supercapacitor exhibits a high specific capacitance and good cycle stability, which has enormous potential applied in wearable and portable electronic products in the future.
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31

Chen, You-Feng, e 陳有豐. "Flexible solid-state oxide supercapacitors and their capacitive performances: fabrication of manganese oxides with porous framework on flexible textiles". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/87171432857161768606.

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碩士
國立中興大學
化學系所
103
In this study, three dimensional (3D) porous MnO2 networks assembled from interconnected MnO2 nanosheets onto carbon nanotube flexible textile substrates have been prepared by a simple and fast electrodeposition method. With such unique 3D networks, enhance electrolyte-accessible surface areas and facilitate easy access of electrolyte ions into the interior of the electrodes can be achieved, which can result in good electrochemical capacitive properties. We use the 3D porous MnO2 networks materials as the electrode and the poly(vinyl alcohol) as the electrolyte to fabricate flexible solid-state supercapacitors, which exhibits a high specific capacitance of 342.1 F/g at 0.5 A/g, comparable energy density and power density, good cycling stability of ~75 % capacity retention and 90 % Coulombic efficiency after 5000 cycles, and good mechanical flexibility. These results indicate that our device can be expected to be promising for the application in flexible energy storage systems.
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32

Chiu, Hsin-Ya, e 邱欣雅. "Application of Mixed-Phase MnO2/N-Containing Graphene Composites to Flexible Asymmetric Solid-State Supercapacitors". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7vz3t7.

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碩士
國立暨南國際大學
應用材料及光電工程學系
107
In this study, the electrode active materials of supercapacitors were prepared by a low-cost facile hydrothermal approach. The N-containing graphene/MnO2 composites (x-NGM) were obtained by growing α- and γ-phase MnO2 nanostructures on the surface of N-containing graphene. A PVA/LiCl electrolyte gel membrane was employed as the separator between two electrodes for supercapacitors. By changing the content of Mn and adjusting the mass loading of active materials, the capacitance characteristics of various electrodes and devices were investigated. Excessive Mn contents were proven to be detrimental to ion transport and faradaic charge transfer, and inferior capacitance characteristics were thereby resulted. Too much mass loading was also demonstrated to decrease conductivity, leading to worse capacitor performance. After calculation by CV results, the 3-NGM1//G1 device exhibited the highest specific capacitance of 579 F·g-1. The corresponding energy and power densities were 73.6 Wh·kg-1 and 4400.0 W·kg-1, respectively, implying its rapid charge/discharge capacity. After 2000 bending cycles under the current density of 1 A·g-1 by GCD method, the retention rate of specific capacitance was found to be around 86.71 %. The high flexibility, cycling stability, and good capacitance properties could be attributed to the synergistic effect of mixed-phase MnO2 and N-containing graphene. By combining the electric double-layer material with pseudo-capacitance materials, the two charge storage mechanisms were joint to improve charge transfer, conductivity, and thus capacitor performance.
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33

Wang, Jeng-An, e 王政安. "Preparation and Characterization of Novel Bifunctional Waterborne Polyurethane-Potassium Poly(acrylate) Polymer for Flexible Supercapacitors". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/5nqd84.

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博士
國立清華大學
化學工程學系
107
This study focuses on the preparation and the performance of the supercapacitor for energy storage devices. The research topics of this dissertation are related to the preparation and properties of novel absorbent polymer, polyurethane - potassium poly(acrylate) (WPU-PAAK), which not only forms the gel polymer electrolyte but also substitutes the commercial binder between electrode materials. There are three parts in this study: (1) Synthesis and characterization of the novel polymer for the electrolyte and adhesive in flexible all-solid-state electrical double-layer capacitors. (2) Mechanism of bi-functional WPU-PAAK polymer in both electrodes and electrolyte. (3) High performance asymmetric supercapacitor NaxMnO2@CNT /WPU-PAAK/AC-CNT The objective of the first part (chapter 3) of this dissertation is to develop a sticky network copolymer, WPU-PAAK. The cross-linked structure is believed to not only enhance the water retention but also provide the mechanical strength in gel polymer electrolyte (GPE). This interesting polymer can avoid the swelling or drying of GPE due to its naturally adsorption/desorption of moisture from the ambient environment. This polymer neutralized with 1 M KOH and soaked with various alkaline solutions (denoted as WPU-PAAK-M, M: Li, Na, K) which can act not only as an electrolyte but also as an adhesive for both positive and negative electrodes for flexible quasi solid-state electrical double-layer capacitors (EDLCs). The PAA backbone chains in the copolymer increase the amount of carboxyl groups and promote the segmental motion. The carboxyl groups enhance the water-uptake capacity which facilitates the ion transport and therefore improves the ionic conductivity. The cross-linked agent, WPU chains, effectively keeps the water content and provides the unique stickiness to serve as a binder for electrodes. The WPU-PAAK soaked with alkaline solutions exhibits an ionic conductivity which is greater than 10-2 S cm-1. A commercial available carbon paper treated with acidic solutions (denoted as ACP) demonstrates excellent capacitive behavior using the WPU-PAAK-K polymer electrolyte. From the cyclic voltammetric test, this ACP shows a high area capacitance of 211.6 mF cm-2 at 10 mV s-1. In the electrochemical impedance spectroscopic analysis, a full cell of ACP/WPU-PAAK-K/ACP displays a low equivalent series resistance of 0.44 Ω in comparison with the other cells using commercial available polymer electrolytes. A quasi solid-state ACP/WPU-PAAK-K/ACP EDLC provides an excellent specific capacitance of 35.5 mF cm-2 at 0.5 mA cm-2. This device with over 90 % capacitance retention under 180o bending angle shows an outstanding flexibility. The objective of the second part (chapter 4) is to develop a high performance supercapacitor by generating the ionic tunnel in the electrode material. To further enhance the performance of flexible supercapacitor, a high surface area (~2500 m2/g) activated carbon, namely ACS 25, was used as electrode material in this study. And the commercial binder of poly(vinylidene fluoride) (PVDF) was substituted by WPU-PAAK in electrode materials. This hydrogel of WPU-PAAK not only acted as the adhesive between each particle of electrode active materials, but also formed the ionic tunnel in the electrode materials, which can more deeply bring the electrolyte ions into the inner site of active materials to enhance the effective area in the interface of electrode and electrolyte. The results show that WPU-PAAK binder in substitution for PVDF binder can enhance the specific capacitance of active electrode about 64 % in current density of 1 A/g. In the high current density of 10 A/g, it can even enhance over 100 % in specific capacitance. Furthermore, the areal specific capacitance of active electrode, which used the WPU-PAAK binder, was increased with the increasing of mass loading in the same ratio. The quasi solid-state device of the sandwich type demonstrates a potential window of 1.4 V and a high device-areal specific capacitance of 122.43 mF cm-2 at 1 mA cm-2. This highly flexible electrical double-layer capacitor (over 95.6 % areal specific capacitance retention at a bending angle of 180o) also delivers an energy density of 33.33 Wh cm-2 at a power density of 0.7 mW cm-2 with an excellent cycle life of 87.5% retention in the 10,000-cycle test. The objective of the third part (chapter 5) is to develop a high performance supercapacitor by enhancing the specific capacitance and potential window. Therefore, this study tries to use the pre-intercalation of Na+ in MnO2 to improve the pseudocapacitance, and also building NaxMnO2@CNT/AC-CNT asymmetrical assembly to enlarge the potential window. According to our previous research, the pre-intercalution of Na+ can optimize the redox reaction in MnO2 to increase the specific capacitance. In addition, the use of CNTs could be beneficial to optimize the electronic conductivity in MnO2. Therefore, this study will explore the performance optimization in the ratio of CNT and NaxMnO2. From the results, NaxMnO2@CNT21 shows the best electrochemical performance. Which exhibits the highest specific capancitance of 150 and 130 F/g at current density of 1 and 20 A/g in 1 M Na2SO4 electrolyte. Furthermore, the specific capacitance of NaxMnO2@CNT21 can be further increased to 330.2 and 140.4 F/g at different current densities in WPU-PAAK-1M Na2SO4 gel polymer electrolyte. This quasi solid-state asymmetrical device, NaxMnO2@CNT21/WPU-PAAK-1M Na2SO4/AC-CNT, shows a potential window of 1.53 V and a high device-areal specific capacitance, specific energy density and specific power density of 301.9 mF cm-2, 130.51 uWh cm-2 and 1.03 mW cm-2 at 1 mA cm-2, respetively. This highly flexible asymmetrical supercapacitor (over 92.4 % areal specific capacitance retention at a bending angle of 180o) also exhibits an excellent cycle life of 90 % and 72.2 % retention in the 5,000-cycle and 10,000-cycle test.
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34

Lee, Ka Yeung Terence. "Study of Flexible Multi-wall Carbon Nano-tubes / Conductivepolymer Composites for Supercapacitor Applications". Thesis, 2014. http://hdl.handle.net/1807/65575.

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Conductive polymers are promising pseudo capacitive materials as they feature both good conductivity and high capacitance. Formation of composite between conductive polymers and carbon nanotubes is a proven technique in enhancing the material electroactivity. In-situ polymerization of conductive polymers includes polyaniline, polypyrrole and PEDOT: PSS and composite with MWCNT has been successfully achieved. Composites fabricated by using different dopants and their performance were studied. Excellent achieved capacitive performance is due to the combination of pseudo capacitance and double layer capacitance. The MWCNTs content has significant influence on the morphology and structure of the polymerized ECP in the composite. And therefore affects the material conductivity and the charge storage performance. Two electrodes cell performance shows that Ppy/MWCNT composite shows a more promising performance as electrode materials for EC applications in contrast to PANI/MWCNT and PEDOT: PSS/MWCNT composites.
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35

To-WenTsao e 曹多雯. "Fabrication of CsxWO3/reduced graphene oxide/PEDOT:PSS nano-hybrids for flexible all-solid-state transparent supercapacitors". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/97djq2.

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36

Qui, Le Van, e 黎文規. "van der Waals Heteroepitaxial AZO/NiO on Muscovite for Transparent Flexible Electronic Devices as Memristors and Supercapacitors". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8x5vks.

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博士
國立交通大學
材料科學與工程學系所
107
Multifunctional electronics featuring optical transparency, portability, mechanical flexibility, light-weight and environment-friendly are of great demands for next-generation smart electronics. Memristor and supercapacitor represents the important chains in next-generation devices as the information and/or energy storage components, respectively. In this thesis, nickel oxide (NiO) and aluminum doped zinc oxide (AZO) are fabricated on muscovite via pulsed laser deposition and sputtering method. By changing the morphology of heterostructure are suitable to develop some advantage applications: We design the transparent flexible structure based on van der Waals heteroepitaxial AZO/NiO/AZO/muscovite (ANA/muscovite) for a memristor application. The ANA/muscovite memristor satisfies all the hardest requirements of a transparent soft device such as optical transparency over 80 % in visible light and high performance with an ON/OFF resistance ratio >105, stable endurance to 103 cycles and long retention time of 105 s. In addition, the ANA/muscovite memristor can work at various bending radii down to 5 mm, a mechanical bending after 1000 cycles at a curvature with a radius of 6.5 mm and a high temperature up to 185 oC. On the other hand, AZO nanorod (NRs) and NiO coated AZO NRs on muscovite mica are fabricated via radio frequency magnetron sputtering deposition method. AZO NRs and AZO/NiO NRs exhibit excellent properties as potential electrodes for next-generation applications as good conductivity, high transparency, stable sheet resistance under compressive and tensile strain down to 5 mm bending radius or mechanical strain after 1000 bending cycles. The obtained symmetric solid-state supercapacitor based on these electrodes display good performance with a large areal specific capacitance of 3.4 mF/cm2, long cycle life 1000 times, robust mechanical properties and high chemical stability. These results deliver a concept to open up new opportunities for future applications in transparent flexible information and energy storage.
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37

Jun-YiWu e 吳俊逸. "Fabrication of nano-carbon/PEDOT:PSS hybrid thin films for flexible transparent conductive electrodes and all-solid-state supercapacitors". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/36eb6g.

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碩士
國立成功大學
化學工程學系
104
This thesis concerns the developments of flexible transparent conductive electrodes and supercapacitors using carbon nanotube (CNT), reduced graphene oxide, and their hybrids with conducting polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS). At first, the CNT and rGO-based thin films were fabricated as flexible transparent conductive electrodes by the blade-coating of CNT or graphene oxide (GO) dispersion on polyethylene terephthalate (PET) and the followed GO reduction with hydroiodic acid for the case of GO. The decreases of transmittance and sheet resistance with the increase of layer numbers have been described. Secondly, CNT or GO (0~0.1wt%) was added to the equal volume mixture of PEDOT:PSS and dimethyl sulfoxide (DMSO) to yield homogeneous dispersions. For the case of GO, the dispersion was further microwave-treated to obtain the rGO dispersion. Then, the CNT or rGO dispersion was blade-coated on PET to form the CNT/PEDOT:PSS or rGO/PEDOT:PSS hybrid thin films as flexible transparent conductive electrodes. It was found that the appropriate addition of CNT or rGO indeed could effectively enhance the conductivity via the formation of conductive network. The lowest sheet resistance around 1000 Ω with a transmittance above 80% was obtained for both the hybrid thin films. Finally, it was demonstrated that both the CNT/PEDOT:PSS and rGO/PEDOT:PSS hybrid thin films also could be used as the electrodes for supercapacitors. The capacitance could be raised by appropriately increasing the thickness of hybrid thin films. Furthermore, the flexible transparent all-solid-state supercapacitors were fabricated with polyvinyl alcohol/sulfuric acid (PVA/H2SO4) gel electrolyte between two CNT/PEDOT:PSS or rGO/PEDOT:PSS hybrid thin film-based electrodes. It was found that both the resulting supercapacitors had transmittances above 56% and could be quickly charged and discharged. Also, their electrochemical performance could be retained while bending. All the results revealed that both the CNT/PEDOT:PSS and rGO/PEDOT:PSS hybrid thin films could be developed as good electrode materials for flexible transparent supercapacitors.
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38

Liao, Chen-Yu, e 廖振宇. "Flexible polyaniline/graphene nanocomposite supercapacitor". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/6zfjdz.

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碩士
國立臺灣大學
應用力學研究所
105
We investigate polyaniline (PANI)/reduced graphene oxide (rGO) composite supercapacitor post-annealed at various temperatures. Pastes containing PANI and rGO are first screen-printed onto carbon cloth. Following which the sample was annealed at 100, 200, and 300 °C for 10 min. Thermogravimetric analysis indicates the decomposition of PANI as the annealing temperature increased to 200 and 300 °C, the pseudocapacitance contributed by PANI decreases, and the capacitance values therefore decreased. 100 °C×10 min annealing can increase the areal capacitance from 88.55 mF/cm2 to 102.73 mF/cm2. Under bending with a bending radius of 0.55 cm, the capacitance retention rate is 90.7 %. After 1000 cycle CV stability test, the capacitance retention rate is 88.25 %.
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39

Chen, Zhi-Hong, e 陳志宏. "Nickel-based thin film supercapacitior electrodes on flexible substrates". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/8e9g7h.

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碩士
義守大學
材料科學與工程學系
103
In this study, electroless Nickel and Nickel – Cobalt coatings were deposited on three kinds of flexible substrates (graphite paper, titanium foil, carbon fiber paper), and these coatings further etched in a 5M HNO3 solution to improve the electrochemical characteristics. Using a three-pole electrode system, cyclic voltammetry and charge-discharge curve were measured to calculate the specific capacitance, and electrochemical impedance spectroscopy (EIS) was used to analyze the electrochemical reaction mechanisms. In addition, the effects of Ni/Co ratios of Ni-Co-P system and etching time on the microstructure and the specific capacitance were explored in details. The results showed that nickel-phosphorus coating on the graphite paper substrate exhibited the highest specific capacitance (71 F/g) than the others (Titanium foil: 30 F/g; carbon fiber paper: 52 F/g) under the same plating conditions. After etching in HNO3 solution for 10s, the specific capacitance of Ni-P coating on graphite paper increased up to 335 F/g, in which the specific capacitance of Ni-P coating increase to 4.7 times as compared with the unetched one. Once the etching time was further increased, it did not significantly increase the specific capacitance. Microstructures analysis revealed that an appropriate etching time can effectively increase the surface area of Ni-P coatings and the prolonged etching time damaged the Ni-P coatings and finally the etched coatings peeled off. To deposit Ni-Co-P coatings on graphite paper, the pH value of electroless bath should be changed into 9. The specific capacitance value is not significantly improved by the addition of Co, but the corrosion resistance of the coating is improved. After etching in 5M nitric acid solution, it also significantly raised specific capacitance, for Ni/Co=70/30 system, at a scan rate of 10mV/s, from 51 F/g to 237 F/g. Based on the above the results, the acid-etching treatment effectively increased the specific capacitance of the Ni-P and Ni-Co-P system, it is expected that such method be applied to other material systems.
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40

Chang, Cheng-Ming, e 張正明. "Biotemplate Hierarchical Polyaniline Composite Films for High Performance Flexible Supercapacitor Devices". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/13773405163797263332.

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博士
中原大學
化學研究所
104
Highly flexible and foldable supercapacitor devices assembled using biotemplated polyaniline composite electrodes are described for the first time in this paper. This electrode architecture provides a facile fabrication route for creating abundant multiscale structures by using a plant species design based on nature resources and facilitates designing a hierarchical ordering morphology that improves the redox exchange and ionic diffusion resistance between the electrodes and electrolyte. The polyaniline composite was prepared using a replica technique and synthetized through in-situ oxidative polymerization by using aniline with conductive carbon materials. The biotemplated electrodes show a high electrochemical specific capacitance of 626 F g−1 in a three-electrode system, an excellent mechanical strength for enduring Z-type folding, and high cycling stability with capacity retention of 87% (545 F g−1). Furthermore, in cyclic voltammetry analysis, the prototype devices exhibit extraordinary elasticity without side reactions in various bending angles. Regarding electrochemical performance, the device responds with a high energy density of 5.06 Wh kg−1 and a high power density of 1685 W kg−1 when based on composite thin film electrodes and maintains 85% cycling retention as well as electrode performance after 1000 cycles. This study clearly reveals that fabricating hierarchical polyaniline composite electrodes through biotemplating yields high electrochemical performance and flexibility, making the electrodes useful for application in energy storage devices for portable electronic products.
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41

Kang, Yu-Yao, e 康宇堯. "Fabrication of integrated device with flexible dye-sensitized solar cell and graphene supercapacitor". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/kk9776.

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碩士
國立虎尾科技大學
電子工程系碩士班
107
Currently, flexible surfaces are becoming more common in electronic devices. Electronic devices fabricated on flexible substrates are considered to have potential. Flexible supercapacitors with long cycle life, high power density, stability and flexibility.In this study, a flexible supercapacitor was prepared activated carbon-doped graphene, and integrated a flexible dye-sensitized solar cell, completed energy conversion/storage components.Baking method for making activated carbon doped graphene carbon powder, carbon-doped graphene paste is used supercapacitor electrode by spin coating. Using a press machine to transfer, TiO2 film on the quartz substrate can transfer the TiO2 film on the ITO/PEN plastic substrate after high temperature sintering, Complete flexible dye-sensitized solar cell. The sample doped 0.05wt% graphene had the best capacitance value. The capacitance value of 218F/g,the charge and 85% of charge/discharge efficiency. The flexible supercapacitor maintained its supercapacitor performance well, even under twisted, bent, or rolled conditions. The flexible dye Sensitized solar cell photoelectric conversion efficiency of 2.5%, integrated components for serial and parallel connection to successfully illuminate the LED.
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42

Chen, Yu-Liang, e 陳昱良. "Au Nanostructures on Flexible Substrate: Fabrication and Applications in Biosensor and Supercapacito". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/99674687789499474579.

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博士
國立交通大學
應用化學系碩博士班
102
In this thesis, we studied fabrication of Au nanostructures on flexible substrate and its applications in biosensor and supercapacitor. A facile fabrication of high density Au nanostructures including nanothorns (NTs), nanocorals (NCs), nanoslices (NSs), and nanowires (NWs) which were electrochemically grown on flexible plastic substrates of polyethylene terephthalate (PET). By adjusting the electroplating conditions, we proposed a growth mechanism of Au nanostructures. Among them, the specific real surface area (RSA) of the Au NWs is the highest one (26100 cm2/g). This is due to the high aspect ratio of the one-dimensional NW structure. Further, as-fabricated Au nanostructures on flexible substrate were employed and used as electrode in biosensor and supercapacitor applications. For biosensor application, a thrombin-binding aptamer was immobilized on the surfaces of the Au nanostructures to form highly sensitive electrochemical impedance spectroscopic (EIS) as biosensors for thrombin recognition. The binding of thrombin to the aptamer was monitored by EIS in the presence of [Fe(CN)6]3-/4-(aq). The protein (1 – 50 pM) was detected linearly by the Au nanostructures. Among them, the Au NWs exhibited excellent thrombin detection performances (1130  pM-1 cm-2). The biosensor provided high sensitivity, selectivity, and stability due to its high surface area. For supercapacitor application, electrodes composed of ultrathin MnO2 (thickness 5 - 80 nm) spines on Au NW stems (length 10 - 20 μm, diameter 20 - 100 nm) were electrochemically grown on flexible PET substrates. The electrodes demonstrated high specific capacitance, high specific energy value, high specific power value, and long-term stability. In Na2SO4(aq) (1 M), the maximum specific capacitance was determined to be 1130 F/g by cyclic voltammetry (CV, scan rate 2 mV/s) using a three-electrode system. From a galvanostatic (GV) charge/discharge test using a two-electrode system, a maximum capacitance 225 F/g (current density 1 A/g) was measured. Even at a high charge/discharge rate 50 A/g, the specific capacitance remained at an extremely high value 165 F/g. The flexible electrodes also exhibited a maximum specific energy 15 Wh/kg and a specific power 20 kW/kg at 50 A/g. After five thousand cycles at 10 A/g, 90% of the original capacitance was retained. A highly flexible solid-state device was also fabricated to reveal its supercapacitance performance.
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43

Sari, Nurlia Pramita, e 薩敏娜. "Three-Dimensional Electrode Self-Assembly of Electrochemical Exfoliated Graphene for High-Performance Flexible Supercapacitor". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/99119505804009136969.

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碩士
國立中央大學
機械工程學系
104
In this study, we report a flexible supercapacitor including a unique macroporosity self-assembly of graphene as electrode. The graphene supercapacitor made by three-dimensional graphene electrodes were prepared by electrochemical exfoliated graphene (EC-graphene) follow by freeze-dried and annealed process. Here we study the effects of macroporous structured electrodes on capacitor performance by altering the graphene concentration. Moreover, flexible supercapacitor devices made by such unique electrodes were demonstrated by using gel electrolyte (1M H2SO4 /PVA). We found out the pore size of 3D graphene electrodes correlated to the solution concentration of initial graphene suspension, where the pore size were 4.88μm, 1.19μm, 1.02μm, 0.39μm corresponding to 10 mg/mL, 15 mg/mL, 20 mg/mL, and 25 mg/mL, respectively. The result shows that graphene electrode exhibit superior high specific capacitance of 45.40 F/g in liquid electrolyte (6M KOH) and 23.89 F/g in gel electrolyte (1M H2SO4/PVA) at low concentration of graphene (10mg/mL), which was higher than that (31.85 F/g in liquid electrolyte and 10.43 F/g in gel electrolyte) of samples prepared at high concentration (25 mg/mL). The device shows excellent rate performance and cycling stability. It was clearly seen the larger pore sized electrodes, result in higher capacitance which was due to few-layered stacked graphene creating more accessible surface area and better kinetic process of ion diffusion. In addition, it can be seen that the dipping method can be used to gain higher performance of flexible supercapacitor. The specific capacitance of EC-graphene without dip is 17.23 F/g (27.91% lower than dipping method). This can be caused by higher efficient ion diffusion in sample dips into dilute PVA-H2SO4 electrolyte due to more time electrolyte immersed into electrode. Moreover, it was found out that EC-graphene shows higher performance than conventional used reduced graphene oxide(rGO) (43.45 F/g in 6M KOH electrolyte), which was attributed to its poor electrical conductivity (sheet resistance of rGO 7.07x10-3 Ω/sq while EC-Graphene 6.60 x10-3 Ω/sq) and lower oxygen functional groups. The flexible supercapacitor, exhibit superior working stability during the bending testing, where 94% of capacitance was preserved for bending angle up to 180o and 90% after 50 times bending cycles. This work introduces a new concept of flexible, environment friendly, large scale production, and high performance graphene-based supercapacitors that could have a way for practical applications in energy devices.
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44

Lien, Chieh, e 連婕. "The Study and Application of Nickel-based GNS/Plant Fiber in Flexible Asymmetric Supercapacitor". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/34454105435082920334.

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碩士
國立中興大學
化學工程學系所
102
As the supercapacitors can provide a higher power density than conventional batteries, it has become a potential application in the energy storage device. Asymmetric supercapacitor is assembled by two slightly different electrode''s materials, and the operating voltage can be enhanced and the capacities and energy densities also be dramatically improved. In this study, we have combined the excellent electric properties of graphene with the flexibility of the plant fibers into a flexible composite electrode, and finally assembled into symmetric and asymmetric supercapacitor. Graphene are uniformly mixed with plant fibers and dried to form a graphene composite electrode.Using electroless plating method to plate nickel on the surface of graphene sheets composites. By controlling the plating time, we can obtain different ratios of Ni/Graphene. Nickel was partially oxidized to nickel oxide because of high-temperature calcinations. The different ratios of Ni/NiO/Graphene composites then formed as a positive electrode of asymmetric supercapacitor. These composite materials will be tested with TGA, XRD andSEM equipments. With KOH and polymer gel as the electrolyte, we assembled the positive and negative electrodes into asymmetric supercapacitors. By the electrochemical test, the electrochemical properties could be obtained to identify optimal conditions for the preparation of flexible asymmetric supercapacitor. By using KOH as electrolyte, the asymmetric supercapacitor has a capacitance value 77.5 F g-1 at a current density of 0.5A g-1. On the other hand, the flexible asymmetric supercapacitor still maintain its own characteristic during bending, showing good flexibility. It has a capacitance value 34.61 F g-1 at a current density of 0.2A g-1. The supercapacitor exhibits excellent stability with nearly no decrease after 500 cycles.
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45

Cheong, Sh-Shen, e 鍾思森. "Fabrication and application of metal oxide/carbon-based material/polyaniline nanocomposites for high-performance flexible supercapacitor". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/j274n4.

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碩士
國立臺灣大學
材料科學與工程學研究所
106
Flexible electronic devices have great potential as a new generation, light weight, flexible wearable applications for healthcare, communication and sportswear. The flexible supercapacitors are one of the most promising candidates due to their long cycle stability, high power density and safety. In this thesis a binary composites of oxidized carbon nanotube or graphene/PANI, ternary composites of oxidized carbon nanotube/graphene/PANI and quaternary composites of metal oxides/oxidized carbon nanotube/graphene/PANI were prepared by electro-polymerization deposition on carbon fiber and carbon cloth respectively. Their surface morphology and compositions were investigated by scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDX) and Fourier transform infrared spectroscopy (FTIR). The results conform the formation of composite material. The particle size and size distribution of the metal oxides were measured by transmission electron microscopy (TEM), X-ray diffraction (XRD) and dynamic light scattering (DLS). Electrochemical measurements including galvanostatic charge discharge, cyclic voltammetry and electrochemical impedance were employed to evaluate their specific capacitance. The highest specific capacitances reach to 1084F/g, 888F/g, and 804F/g at 1A/g and 803F/g, 563F/g, and 371F/g at 20A/g for oxidized carbon nanotube/graphene/PANI composites incorporating with 1wt%RuO2, 2wt%MnO2 and 1wt%NiO respectively. Flexible Symmetrical Supercapacitor (FSSC) were also fabricated by using GO/EMITFSI ionic liquid composite as gel type electrolyte. The FSSC shows a remarkable performance including good capacitance (513 F/g, 478 F/g, 441 F/g, 431 F/g, 394 F/g at 1A/g for 1wt%RuO2/oxidized carbon nanotube/graphene/PANI, 2wt% MnO2 oxidized carbon nanotube/graphene/PANI, 1wt%NiO/ oxidized carbon nanotube/graphene/PANI respectively), great capability retention at 20A/g and excellent cycle life. 1wt%RuO2/oxidized carbon nanotube/graphene/PANI shows the maximum energy density of 37Wh/kg and the highest power density of 13kW/kg. We also demonstrate actual performance of FSSC by lighting up a red LED. Therefore, our study for flexible supercapacitor holds great potential for next generation lightweight and flexible electronics.
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46

Huang, Tse-Yu, e 黃則毓. "Fabrication and applications of metal oxide/nano-carbon material/polypyrrole nanocomposite electrodes for high-performance flexible supercapacitor". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/y22j56.

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碩士
國立臺灣大學
材料科學與工程學研究所
106
Supercapacitors can be applied to communication and healthcare industries due to their high power density, long cycle life and friendly to environment. Because flexible supercapacitors have convenience to personal life, they have great potential to develop as a next-generation and wearable electronic gadget. Our purpose of research is to fabricate a supercapacitor device with high specific capacitance, high energy density, high power density and long cycle life. In our research, electrode of polypyrrole(PPy), binary system electrode of graphene/PPy and oxidized carbon nanotube/PPy, ternary system electrode of graphene/oxidized carbon nanotube/PPy and quaternary system electrode of metal oxide(RuO2, MnO2 or NiO)/graphene/oxidized carbon nanotube/PPy were individualy prepared by electrochemical polymerization deposition on carbon fiber and carbon cloth respectively, and we adjusted parameters of different compositions of materials and polymerization time in this experiment. We also used Fourier transform infrared spectroscopy(FTIR) to investigate the interaction between materials, scanning electron microscopy(SEM) to investigate the surface morphology and energy dispersive X-ray microanalysis(EDX) to analyze the compositions of quaternary electrode. We used galvanic charge-discharge method and cyclic voltammetry to analyze the electrochemical properties of electrodes. For the system of carbon cloth substrate, the quaternary electrode of RuO2/graphene/oxidized carbon nanotube/PPy with polymerization time of 300s has the best specific capacitance of 1017.1F/g at current density 1A/g measured by galvanic charge-discharge method and has specific capacitance retention of 70.8% at 20A/g. It also has the best specific capacitance of 1034.1F/g at scan rate 5mV/s measured by cyclic voltammetry, and has specific capacitance retention of 70.1% at 100mV/s. We further fabricated the flexible symmetric supercapacitor device(SSC) with above mentioned electrodes by using GO/EMITFSI as gel electrolyte and used galvanic charge-discharge, cyclic voltammetry and electrochemical impedance to analyze the electrochemical properties of devices. SSCs with symmetric electrodes of RuO2/graphene/oxidized carbon nanotube/PPy, MnO2/graphene/oxidized carbon nanotube/PPy, NiO2/graphene/oxidized carbon nanotube/PPy, graphene/oxidized carbon nanotube/PPy and PPy have the highest specific capacitance of 561.6F/g, 517.1F/g, 475.9F/g, 370F/g and 322.9F/g at current density 1A/g and have specific capacitance retention of 44.3%, 43.5%, 44.5%, 56% and 41% at 20A/g respectively. Their specific capacitances at scan rate of 5mV/s were 589.5F/g, 535F/g, 489.8F/g, 384.2F/g and 335F/g at scan rate 5mV/s with the specific capacitance retention of 44.1%, 44.2%, 44.1%, 54.3% and 44.2% at 100mV/s respectively. We found the device of RuO2/graphene/oxidized carbon nanotube/PPy has the best specific capacitance and energy density of 38.11Wh/kg and has specific capacitance retention of 89.5% after 1000 charge-discharge cycle. Finally, we use four devices of RuO2/graphene/oxidized carbon nanotube/PPy in series to light up a red LED to demonstrate our SSCs having great potential for next generation electronic gadgets.
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47

Su, Dung-Yue, e 蘇東裕. "Silver nanowires and graphene sheets apply on applications of flexible electrode, supercapacitor and stretchable gas-permeation barrier". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/64n2p7.

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博士
國立臺灣大學
材料科學與工程學研究所
107
The dissertation focus on development of flexible electrode and stretchable gas barrier. For the field of flexible electrodes, synthesis of silver nanowires (AgNWs) and integration of AgNWs with atomic layer deposition (ALD) in flexible electrodes and supercapacitors were studied to address the key issues of flexible electronics: (i) nature brittle and insufficient performance of indium tin oxide (ITO), which is current dominant material of transparent conductive electrode, and (ii) major goal of energy storage: high capacitance and cost-effective fabrication. In the part of synthesis of silver nanowires, we developed a solution processed route to synthesize silver nanowires with high aspect ratio in ambient condition through optimizing copper bromide concentration and injection of ultrasonic atomization of silver precursor. In the part of transparent conductive gas barrier, we utilized a novel ALD hafnium-doped zinc oxide (HZO) process, a good transparent conductive gas barrier process developed in our laboratory. To deposited thin HZO layer with plastic-compatible temperature, excellent gas barrier performance and flexibility, integrating with silver nanowires film and H2O2 treatment of AgNWs interfaces, we successfully developed a HZO/AgNW hybrid transparent conductive gas barrier with performance superior to ITO/PET. In addition, we also demonstrated the feasibility of the HZO/AgNW hybrid film for perovskite solar cells, which can simultaneously as transparent electrode and electron collection layer, and the cells using hybrid films displayed slightly better photovoltaic performance than the devices using commercial ITO as electrode. In the part of supercapacitor, we utilized high surface-area silver nanowires network, which could be fabricated by spray coating of silver nanowires, and integrating with ALD dielectric and conductive layer to fabricate supercapacitor with high volumetric capacitance (193.5 mF/cm3). In the part of stretchable gas barrier, we utilized solvent exchange method, which could significantly improve graphene dispersibility in polyurethane. Therefore, tortuous path of gas in polyurethane was prolonged, and resulting in respectable WVTR reduction, and its comprehensive properties were improved.
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48

Chen, Po-Hsiang, e 陳柏翔. "The Fabrication of Modified Graphene sheet and Electrospun Polyamide 6,6 Fiber Nanocomposite and its Application in Flexible Electrode for Supercapacitor". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/07184258444513484567.

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49

TAI, WEI-CHING, e 戴瑋慶. "Electrochemical deposition and characterization of MnO2/rGO on porous nickel of inverse opal structures on a flexible substrate for supercapacitor applications". Thesis, 2019. http://ndltd.ncl.edu.tw/handle/fm22kz.

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碩士
逢甲大學
材料科學與工程學系
107
This work is consisted of five experimental procedures including (i) formation of graphene oxide (GO) via Hummers' method, (ii) production of photonic crystals (PhCs) of PS microspheres on the ITO glass substrates via electrophoretic self-assembly (EPSA) route, (iii) development of template-mediated technique to create a nickel inverse opal structure (IOS) via electrochemical deposition (ECD), (iv) MnO2/Ni foam, MnO2/rGO/Ni foam and MnO2/rGO/Ni-IOS samples were prepared by ECD, and (v) sample property analysis of their microstructure structures and electrochemical characteristics. We successfully fabricated the 3-D PhCs of PS microspheres, which were of various size-distributed and well-dispersed features via emulsifier-free polymerization. Tuning electrochemical deposition time is able to control the thickness of the structure of nickel metal PhCs with invers opal structure. Electrochemical deposition of rGO/Ni-IOS through deposition voltage and deposition time led to the optimal electrochemical characteristics, and then the MnO2/rGO/Ni-IOS structure electrode of supercapacitor sample made by ECD route with constant voltage of 0.4 V and deposition time of 3 min had a rather outstanding specific capacitance of 2,060 F/g under a charging-discharging (CD) test at current density of 2 A/g. The specific capacitance of such a sample can still maintain at 91% level of the original specific capacitance after 2,000 cycles. In this study, we successfully demonstrated that the fabrication of a unique composite of nickel sulfide active media and a highly porous nickel metal media in an inverse opal structure prepared by EPSA and ECD can provide a great contribution for designing novel supercapacitor devices.
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50

Bandari, Vineeth. "Towards Smart Motile Autonomous Robotic Tubular Systems (S.M.A.R.T.S)". 2021. https://monarch.qucosa.de/id/qucosa%3A75964.

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The development of synthetic life once envisioned by Feynman and Flynn many decades ago has stimulated significant research in materials science, biology, neuroscience, robotics, and computer science. The cross-disciplinary effort and advanced technologies in soft miniature robotics have addressed some of the significant challenges of actuation, sensing, and subsystem integration. An ideal Soft motile miniaturised robot (SMMRs) has innovative applications on a small scale, for instance, drug delivery to environmental remediation. Such a system demands smart integration of micro/nano components such as engines, actuators, sensors, controllers, and power supplies, making it possible to implement complex missions controlled wirelessly. Such an autonomous SMMR spans over multiple science and technology disciplines and requires innovative microsystem design and materials. Over the past decade, tremendous efforts have been made towards mastering one of such a SMMR's essential components: micro-engine. Chemical fuels and magnetic fields have been employed to power the micro-engines. However, it was realized seven years ago in work of TU-Chemnitz Professorship of Material Systems in Nanoelectronics and institute of investigative Nanosciences Leibniz IFW Dresden including Chemnitz side. Write explicitly that it is essential to combine the micro-engine with other functional microelectronic components to create an individually addressable smart and motile microsystem. This PhD work summarises the progress in designing and developing a novel flexible and motile soft micro autonomous robotic tubular systems (SMARTS) different from the well-studied single-tube catalytic micro-engines and other reported micromotors. Our systems incorporate polymeric nanomembranes fabricated by photolithography and rolled-up nanotechnology, which provide twin-tube structures and a spacious platform between the engines used to integrate onboard electronics. Energy can be wirelessly transferred to the catalytic tubular engine, allowing control over the SMARTS direction. Furthermore, to have more functionality onboard, a micro-robotic arm was integrated with remote triggering ability by inductive heating. To make the entire system smart, it is necessary to develop an onboard processor. However, the use of conventional Si technology is technically challenging due to the high thermal processes. We developed complex integrated circuits (IC) using novel single crystal-like organic and ZnO-based transistors to overcome this issue. Furthermore, a novel fabrication methodology that combines with six primary components of an autonomous system, namely motion, structure, onboard energy, processor, actuators, and sensors to developing novel SMARTSs, is being pursued and discussed.:List of acronyms 8 Chapter 1. Introduction 12 1.1 Motivation 14 1.2 Objectives 17 1.3 Thesis structure 18 Chapter 2. Building blocks of micro synthetic life 19 2.1 Soft structure 20 2.1.1 Polymorphic adaptability 20 2.1.2 Dynamic reconfigurability 20 2.1.3 Continuous motion 21 2.2 Locomotion 21 2.2.1 Aquatic 22 2.2.2 State-of-the-art aquatic SMMR 24 2.2.3 State-of-the-art terrestrial SMMR 25 2.2.4 State-of-the-art aerial SMMR 27 2.3 Onboard sensing 28 2.3.1 State-of-the-art 3D and flexible sensors systems 28 2.4 Onboard actuation 30 2.4.1 State-of-the-art actuators 30 2.5 Embedded onboard intelligence 32 2.5.1 State-of-the-art flexible integrated circuits 32 2.6 Onboard energy 33 2.6.1 State-of-the-art micro energy storage 34 2.6.2 State-of-the-art onboard energy harvesting SMMR 35 Chapter 3. Technology overview 38 3.1 Structure 38 3.1.1 Self-assembled “swiss-roll” architectures 40 3.1.2 Polymeric “swiss-roll” architectures 41 3.2 Motion: micro tubes as propulsion engines 44 3.2.1 Chemical engines 44 3.3 Embedded onboard intelligence 46 3.3.1 Thin film transistor 46 3.3.2 Basic characteristics of MOSFETs 48 3.4 Growth dynamics of organic single crystal films 51 3.4.1 Thin films growth dynamics 52 3.5 Powering SMARTSs 55 3.5.1 Onboard energy storage 56 3.5.2 Wireless power delivery 59 3.6 Integrable micro-arm 63 3.6.1 Stimuli-responsive actuator 63 3.6.2 Remote activation 64 Chapter 4. Fabrication and characterization 65 4.1 Thin film fabrication technology 65 4.1.1 Photolithography 65 4.1.2 E-beam deposition 68 4.1.3 Sputtering 69 4.1.4 Physical vapour deposition 70 4.1.5 Atomic layer deposition 71 4.1.6 Ion beam etching 72 4.2 Characterization methods 73 4.2.1 Atomic force microscopy 73 4.2.2 Scanning electron microscopy 74 4.2.3 Cyclic voltammetry 75 4.2.4 Galvanic charge discharge 77 4.2.5 Electrochemical impedance spectroscopy 78 Chapter 5. Development of soft micro autonomous robotic tubular systems (SMARTS) 81 5.1 Soft, flexible and robust polymeric platform 82 5.2 Locomotion of SMARTS 84 5.2.1 Assembly of polymeric tubular jet engines 84 5.2.2 Catalytic self-propulsion of soft motile microsystem 85 5.2.3 Propulsion power generated by the catalyst reaction 87 5.3 Onboard energy for SMARTS 89 5.3.1 Onboard wireless energy 90 5.3.2 Onboard ‘zero-pitch’ micro receiver coil 90 5.3.3 Evaluation of the micro receiver coil 91 5.4 Onboard energy storage 92 5.4.1 Fabrication of nano-biosupercapacitors 93 5.4.2 Electrochemical performance of “Swiss-roll” nBSC 97 5.4.3 Self-discharge performance and Bio enhancement: 98 5.4.4 Electrochemical and structural life time performance 100 5.4.5 Performance under physiologically conditions 101 5.4.6 Electrolyte temperature and flow dependent performance 102 5.4.7 Performance under hemodynamic conditions 105 5.4.8 Biocompatibility of nBSCs 105 5.5 Wireless powering and autarkic operation of SMARTS 108 5.5.1 Remote activation of an onboard IR-LED 108 5.5.2 Wireless locomotion of SMARTS 109 5.5.3 Effect of magnetic moment on SMARTS locomotion 111 5.5.4 Full 2D wireless locomotion control of SMARTS 112 5.5.5 Self-powered monolithic pH sensor system 114 5.6 Onboard remote actuation 119 5.6.1 Fabrication of integrable micro-arm 120 5.6.2 Remote actuation of integrable micro-arm 122 5.7 Flexibility of SMARTS 122 5.8 Onboard integrated electronics 123 5.9 Onboard organic electronics 124 5.9.1 Growth of BTBT-T6 as active semiconductor material 125 5.9.2 Confined Growth of BTBT-T6 to form Single-Crystal-Like Domain 128 5.9.3 Fabrication of OFET based on Single-Crystal-Like BTBT-T6 129 5.9.4 Carrier injection optimization 132 5.9.5 Performance of single-crystal-like BTBT-T6-OFET 133 5.10 Onboard flexible metal oxide electronics 136 5.10.1 Fabrication flexible ZnO TFT 138 5.10.2 Performance of ZnO TFT 139 5.10.3 Flexible integrated circuits 140 5.10.4 Logic gates 140 Chapter 6. Summary 142 Chapter 7. Conclusion and outlook 144 References 147 List of Figures & tables 173 Versicherung 177 Acknowledgement 178 Research achievements 180 Research highlight 183 Cover pages 184 Theses 188 Curriculum-vitae 191
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