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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Electronic Devices Using Open Framework Materials

Feng, Xinliang, Allendorf, Mark D., Dong, Renhao, Kaskel, Stefan, Matoga, DariusZ, Stavila, Vitalie 05 August 2022 (has links)
Open framework materials (OFM) constitute a large and growing class of nanoporous crystalline structures that is attracting considerable attention for electronic device applications. This review summarizes the most recent reports concerning electronic devices enabled by either of the two primary categories of OFM, metal–organic frameworks (MOFs) and covalent–organic frameworks (COFs). Devices in which the OFM plays an active role (as opposed to acting only as a selective sorbent or filter) are the principal focus, with examples cited that include field-effect transistors, capacitors, memristors, and a wide variety of sensing architectures. As a brief tutorial, we also provide a concise summary of various methods of depositing or growing OFM on surfaces, as these are of crucial importance to the deployment of electronic OFM. Finally, we offer our perspective concerning future research directions, particularly regarding what in our view are the biggest challenges remaining to be addressed. On the basis of the literature discussed here, we conclude that OFM constitute a unique class of electronic materials with characteristics and advantages that are distinct from either conventional inorganic semiconductors or organic conductors. This suggests a bright future for these materials in applications such as edge computing, resistive switching, and mechanically flexible sensing and electronics.
22

Magische Linsen an Displaywänden: Steuerung und Bedienung mit Mobilgeräten

Lorenz, Norman 24 October 2017 (has links) (PDF)
Der Einsatz großer, vertikaler Displays nimmt sowohl in Bereichen der Forschung als auch der Wirtschaft zu. Diese Displays eignen sich durch ihre Größe und Auflösung unter anderem für die Informationsvisualisierung. Es gibt bereits eine Menge von Forschungsarbeiten, welche die Interaktion mit großen, vertikalen Displays untersucht hat. Jedoch ist speziell die Bedienung Magischer Linsen auf großen Displaywänden weitgehend unbeachtet geblieben. Eine intuitive Interaktion mit Magischen Linsen auf einer Displaywand kann jedoch insbesondere in kollaborativen Szenarien große Vorteile bieten. Smartphones eignen sich durch ihre Portabilität zur Interaktion mit Displaywänden. Unter Verwendung von Mobilgeräten und einer hochauflösenden Displaywand wurden im Rahmen der vorliegenden Arbeit Interaktionskonzepte zur Steuerung und Parametrisierung Magischer Linsen entwickelt. Hierzu wurde eine Recherche des aktuellen Forschungsstandes betrieben und Anwendungsfälle für den Einsatz der Konzepte aufgestellt. Es wurde eine große Bandbreite von Interaktionskonzepten entwickelt, welche von lockeren bis zu fokussierten Interaktionen reichen. Für die Bedienung der Magischen Linsen wurden verschiedene Aktionen identifiziert, welche in einem Interaktionsablauf auftreten und durch die Konzepte zu unterstützen sind. Ein Teil der entwickelten Interaktionskonzepte wurde durch einen Prototypen implementiert und anhand von Beispieldatensätzen getestet. / The usage of large, vertical displays is increasing in felds of research as well as in the economy. Because of their size and resolution these displays are well suited for information visualization. There already are a number of publications which examine the interaction with large, vertical displays. Yet especially the operation of magic lenses on large display walls has been mostly ignored. An intuitive interaction with magic lenses on a large display may be espesially advantageous in collaborative scenarios. Smartphones are suited for interaction with display walls because of their portability. In this paper interaction concepts for operating and parametrizing magic lenses have been developed using mobile devices and a high resolution display wall. For this purpose the current state of research has been investigated and application scenarios for the use of the concepts have been constructed. A big amount of interaction concepts have been developed which range from casual to focused interactions. For the operation of magic lenses several actions have been identifed which occur in an interaction process and have to be adsressed by the concepts. Part of the developed interaction concepts have been implemented by a prototype and tested with sample data sets.
23

Compact Helical Antenna for Smart Implant Applications

Karnaushenko, Dmitriy D. 06 December 2017 (has links) (PDF)
Medical devices have made a big step forward in the past decades. One of the most noticeable medical events of the twenties century was the development of long-lasting, wireless electronic implants such as identification tags, pacemakers and neuronal stimulators. These devices were only made possible after the development of small scale radio frequency electronics. Small radio electronic circuits provided a way to operate in both transmission and reception mode allowing an implant to communicate with an external world from inside a living organism. Bidirectional communication is a vital feature that has been increasingly implemented in similar systems to continuously record biological parameters, to remotely configure the implant, or to wirelessly stimulate internal organs. Further miniaturisation of implantable devices to make the operation of the device more comfortable for the patient requires rethinking of the whole radio system concept making it both power efficient and of high performance. Nowadays, high data throughput, large bandwidth, and long term operation requires new radio systems to operate at UHF (ultra-high frequency) bands as this is the most suitable for implantable applications. For instance, the MICS (Medical Implant Communication System) band was introduced for the communication with implantable devices. However, this band could only enable communication at low data rates. This was acceptable for the transmission of telemetry data such as heart beat rate, respiratory and temperature with sub Mbps rates. Novel developments such as neuronal and prosthetic implants require significantly higher data rates more than 10 Mbps that can be achieved with large bandwidth communicating systems operating at higher frequencies in a GHz range. Higher operating frequency would also resolve a strong issue of MICS devices, namely the scale of implants defined by dimensions of antennas used at this band. Operation at 2.4 GHz ISM band was recognized to be the most adequate as it has a moderate absorption in the human body providing a compromise between an antenna/implant scale and a total power efficiency of the communicating system. This thesis addresses a key challenge of implantable radio communicating systems namely an efficient and small scale antenna design which allows a high yield fabrication in a microelectronic fashion. It was demonstrated that a helical antenna design allows the designer to precisely tune the operating frequency, input impedance, and bandwidth by changing the geometry of a self-assembled 3D structure defined by an initial 2D planar layout. Novel stimuli responsive materials were synthesized, and the rolled-up technology was explored for fabrication of 5.5-mm-long helical antenna arrays operating in ISM bands at 5.8 and 2.4 GHz. Characterization and various applications of the fabricated antennas are successfully demonstrated in the thesis.
24

Magische Linsen an Displaywänden: Steuerung und Bedienung mit Mobilgeräten

Lorenz, Norman 29 June 2017 (has links)
Der Einsatz großer, vertikaler Displays nimmt sowohl in Bereichen der Forschung als auch der Wirtschaft zu. Diese Displays eignen sich durch ihre Größe und Auflösung unter anderem für die Informationsvisualisierung. Es gibt bereits eine Menge von Forschungsarbeiten, welche die Interaktion mit großen, vertikalen Displays untersucht hat. Jedoch ist speziell die Bedienung Magischer Linsen auf großen Displaywänden weitgehend unbeachtet geblieben. Eine intuitive Interaktion mit Magischen Linsen auf einer Displaywand kann jedoch insbesondere in kollaborativen Szenarien große Vorteile bieten. Smartphones eignen sich durch ihre Portabilität zur Interaktion mit Displaywänden. Unter Verwendung von Mobilgeräten und einer hochauflösenden Displaywand wurden im Rahmen der vorliegenden Arbeit Interaktionskonzepte zur Steuerung und Parametrisierung Magischer Linsen entwickelt. Hierzu wurde eine Recherche des aktuellen Forschungsstandes betrieben und Anwendungsfälle für den Einsatz der Konzepte aufgestellt. Es wurde eine große Bandbreite von Interaktionskonzepten entwickelt, welche von lockeren bis zu fokussierten Interaktionen reichen. Für die Bedienung der Magischen Linsen wurden verschiedene Aktionen identifiziert, welche in einem Interaktionsablauf auftreten und durch die Konzepte zu unterstützen sind. Ein Teil der entwickelten Interaktionskonzepte wurde durch einen Prototypen implementiert und anhand von Beispieldatensätzen getestet. / The usage of large, vertical displays is increasing in felds of research as well as in the economy. Because of their size and resolution these displays are well suited for information visualization. There already are a number of publications which examine the interaction with large, vertical displays. Yet especially the operation of magic lenses on large display walls has been mostly ignored. An intuitive interaction with magic lenses on a large display may be espesially advantageous in collaborative scenarios. Smartphones are suited for interaction with display walls because of their portability. In this paper interaction concepts for operating and parametrizing magic lenses have been developed using mobile devices and a high resolution display wall. For this purpose the current state of research has been investigated and application scenarios for the use of the concepts have been constructed. A big amount of interaction concepts have been developed which range from casual to focused interactions. For the operation of magic lenses several actions have been identifed which occur in an interaction process and have to be adsressed by the concepts. Part of the developed interaction concepts have been implemented by a prototype and tested with sample data sets.
25

Online-Fragebogen auf mobilen Geräten: Ein Layout-Vergleich

Hechtberger, Christian, Nissen, Helge, Janneck, Monique 17 December 2019 (has links)
Die Internetzugriffe über Smartphones steigen jährlich und erreichten im Jahre 2017 eine weltweite Quote von über 50% (StatCounter, 2018). Da die Mehrzahl der Google-Nutzenden von mobilen Endgeräten aus zugreift, indiziert Google seit März 2018 bei Webseiten, die mit dem „mobile-first“-Ansatz erstellt wurden, die mobile Version und nicht mehr wie zuvor in erster Linie die Desktop-Variante (Google, 2018). Bereits diese beiden Umstände verdeutlichen eindrücklich, wie wichtig es ist, Interfaces jeglicher Art für mobile Endgeräte zu optimieren, beziehungsweise erst für mobile Geräte zu entwickeln und diese im Anschluss für größere Bildschirme zu verbessern. Revilla et al. (2014) untersuchten im Jahr 2014 eine Reihe von Umfragen, die in Spanien, Portugal und Südamerika durchgeführt wurden. Sie stellten fest, dass der Großteil der Teilnehmenden, obwohl mehrere Geräte zur Durchführung der Umfrage zur Verfügung standen (z. B. PC und Smartphone), insbesondere das Smartphone für die Beantwortung wählte (Revilla et al., 2014). Tatsächlich werden Online-Fragebogen schon seit einigen Jahren nicht mehr ausschließlich auf Desktop-Computern bearbeitet (Callegaro, 2010). Es zeigt sich vielmehr eine Tendenz zur vermehrten Nutzung mobiler Geräte. Im Jahre 2011 konnten lediglich 4% Smartphone-Teilnehmende verzeichnet werden, im Jahre 2014 waren es hingegen bereits 18% (Sarraf et al., 2014) und in einer aktuellen Studie aus dem Jahr 2018 sogar 33,7% (Nissen & Janneck, 2018b). In diesem Beitrag gehen wir der Frage nach, welche Ergebnisse ein mobil eingesetztes Standard-Layout hinsichtlich der Abbruchquote, der Bearbeitungszeit, des Antwortverhaltens und der User Experience erzielt und ob sich diese Werte mit einem explizit für den mobilen Einsatz entwickelten Layout verbessern lassen. [... aus der Einleitung]
26

Teaching and Learning Creativity in Virtual Settings: A thematic analysis of the factors that hinder or foster creativity through the lenses of an artist

Martinez Borjas, Adriana, Gebbing, Pia 11 March 2022 (has links)
The role of creativity in the economy is seen as crucial to assist nations in attaining higher employment and economic achievement and to cope with increased competition (Davies, 2002,Burnard, 2006). As a consequence, education systems are being required to undergo “a major overhaul in resources, attitudes, and understanding” so that creativity can be valued to manage literacy as a non-linear information structure through different settings (Turner-Bisset, 2007). Nourishing and fostering creativity in all educational settings while using technology as a conduit unlocks the opportunity to produce a highly employable workforce with 21st-century skills. Hence, the major challenge lies in how educators can prepare students by fostering creativity and enhancing 21st-century skills through information and communication technologies (ICT) in a virtual learning environment, referred to as a “virtual setting” in this study. This paper aims to explore the factors that hinder or foster the teaching and learning of creativity in a virtual setting through smart devices by conducting fve expert indepth interviews with “Pro-C” artists from various professional backgrounds and applying a thematic analysis to derive implications for educators and students for using technology as a conduit to enhance creativity [Aus: Introduction]
27

Optimierung des Innovations- und Entwicklungsprozesses von biomedizintechnischen Geräten

Busch, Erik 08 April 2022 (has links)
Objective: Cardiovascular diseases are the leading cause of death. The gold standard for their diagnosis and treatment are angiographic procedures. Clinicians rely on dedicated and specialized equipment for these interventions, e.g. angiography systems. The speed of the associated development is important as better technology enables progress in treatment methods and clinical outcomes. The goal of this article is to show how to optimize the innovation and development process such that it takes minimal time. Methods: 672 data sets on 302 topics were collected over 47 months during a long-term observation of the innovation and development process of angiographic systems. The total data collected is equivalent to efforts worth 30 man-years. This input was used to calculate key process parameters, analyse key process roles, evaluate the use of problem-solving methods and identify key technologies. We also developed a process model comprising the primary innovation sources, important input providers and key processes. This model is characterized by a continuous loop for the innovation and development process. Results: The conducted literature research identifies this closed loop process model as being unique in comparison to the well-established models proposed by Brockhoff, Cooper, Crawford, Durfee, Ebert, Eppinger, Hughes, Pleschak, Thom, Ulrich, Vahs and Witt. According to the best knowledge of the authors no comparable data collection has been performed and presented anywhere else yet. When analysing our 672 data sets, we found that the median process time ( in this data pool (n=672) was to be 10 weeks (p<0,05). The median number of task owners (xPA) per task across all topics was 2. Our data revealed that the number of task owners had a direct impact on the process time. For data sets with up to eight task owners the relationship between process time and task owners can be described as tPd=3.6*xPA^1.4. The median time of owning a topic was determined for Sales (7 weeks), Service (11 weeks), Customer Relationship Management (6 weeks), Product Lifecycle Management (10 weeks) and Research & Development (11 weeks). Main input providers were Sales (53%) and customers (28%). Sales (42%) and PLM (37%) are significant connectors. Problem solvers are PLM (35%), CRM (27%) and R&D (27%). The problem-solving methods were analysed and it was found that clarification (77%) as well as dialog and variation method (both 50%) were used most often. We found that changes to the application software (33%), mechanics, device interfaces and user interface (all 21%) are the four out of six components that were involved in most often. In the analysed datasets a potential of an up to 20% shorter process time was identified. Conclusion: This article proposes a new model for the innovation and development process. Based on our data, we recommend to apply a continuous loop process in the context of innovation and development of medical devices. Our results can, for example, be used for Activity Based Costing Approach or be applied to bring new or upgraded angiography systems faster to market benefitting patient outcome due to improved diagnosis and treatment of cardiovascular diseases.
28

Designing Electrochemical Energy Storage Microdevices: Li-Ion Batteries and Flexible Supercapacitors

Si, Wenping 30 January 2015 (has links) (PDF)
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
29

Compact Helical Antenna for Smart Implant Applications

Karnaushenko, Dmitriy D. 19 October 2017 (has links)
Medical devices have made a big step forward in the past decades. One of the most noticeable medical events of the twenties century was the development of long-lasting, wireless electronic implants such as identification tags, pacemakers and neuronal stimulators. These devices were only made possible after the development of small scale radio frequency electronics. Small radio electronic circuits provided a way to operate in both transmission and reception mode allowing an implant to communicate with an external world from inside a living organism. Bidirectional communication is a vital feature that has been increasingly implemented in similar systems to continuously record biological parameters, to remotely configure the implant, or to wirelessly stimulate internal organs. Further miniaturisation of implantable devices to make the operation of the device more comfortable for the patient requires rethinking of the whole radio system concept making it both power efficient and of high performance. Nowadays, high data throughput, large bandwidth, and long term operation requires new radio systems to operate at UHF (ultra-high frequency) bands as this is the most suitable for implantable applications. For instance, the MICS (Medical Implant Communication System) band was introduced for the communication with implantable devices. However, this band could only enable communication at low data rates. This was acceptable for the transmission of telemetry data such as heart beat rate, respiratory and temperature with sub Mbps rates. Novel developments such as neuronal and prosthetic implants require significantly higher data rates more than 10 Mbps that can be achieved with large bandwidth communicating systems operating at higher frequencies in a GHz range. Higher operating frequency would also resolve a strong issue of MICS devices, namely the scale of implants defined by dimensions of antennas used at this band. Operation at 2.4 GHz ISM band was recognized to be the most adequate as it has a moderate absorption in the human body providing a compromise between an antenna/implant scale and a total power efficiency of the communicating system. This thesis addresses a key challenge of implantable radio communicating systems namely an efficient and small scale antenna design which allows a high yield fabrication in a microelectronic fashion. It was demonstrated that a helical antenna design allows the designer to precisely tune the operating frequency, input impedance, and bandwidth by changing the geometry of a self-assembled 3D structure defined by an initial 2D planar layout. Novel stimuli responsive materials were synthesized, and the rolled-up technology was explored for fabrication of 5.5-mm-long helical antenna arrays operating in ISM bands at 5.8 and 2.4 GHz. Characterization and various applications of the fabricated antennas are successfully demonstrated in the thesis.
30

Designing Electrochemical Energy Storage Microdevices: Li-Ion Batteries and Flexible Supercapacitors

Si, Wenping 22 January 2015 (has links)
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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