10 research outputs found

    2D materials based Nanoelectronic devices for multifunctional sensors

    Get PDF
    Conventional electronic devices deal with rigidity and hence lack of flexibility and stretchablity. A research that is rapidly evolving to develop human friendly flexible and stretchable devices for future electronics. A lot of research has been done on fabricating sensors and electronic devices using 2D materials having characteristics like stretchablity, bendability. These nanomaterials can be used for fabrication of photodetectors, temperature, pressure and strain sensors because of their excellent electronic, thermal, mechanical and optical properties. The second chapter deals with the demonstration of human integrated electronic devices such as RC filters by utilizing flexible capacitor fabricated using few layer MoS2 grown on Al foil via hydrothermal method as electrodes and cellulose paper as a dielectric material. Advantage of using MoS2 on Al foil is the enhanced capacitance upon strain due to the piezoelectric property of few layered MoS2 over monolayer MoS2. Upon application of external strain on capacitor the mathematical operations such as differentiation and integration are observed for different input signal using RC filter circuits. Such a simple technique for fabrication of flexible variable capacitor is a major step ahead in wearable electronics having applications in digital electronics and sensors. The 2-D nanomaterials possesses great optical properties so can be used for photo detection. The second chapter deals with 2D ZnO/Gr pyro-phototronic diode. Even though 2D ZnO has been utilized for enhanced self-powered sensing by strain modulation due to its piezoelectric property, study on utilizing pyroelectric property of ZnO remains unexplored. For pyroelectric nan generator, temperature difference can be triggered by external light source which does not disrupt the ZnO structure and also avoids the need for physical bending/pressing as in case of piezoelectric nanogenerator. This work represents the first demonstration of fabrication of flexible 2D ZnO/Gr pyro-phototronic diode where the pyro potential generated in the 2D ZnO due to the NIR illumination adds/subtract with the built-in electric field of the heterojunction and modulates the depletion region of the heterojunction thereby enabling bias free operation

    The 1st International Electronic Conference on Chemical Sensors and Analytical Chemistry

    Get PDF
    The 1st International Electronic Conference on Chemical Sensors and Analytical Chemistry was held on 1–15 July 2021. The scope of this online conference was to gather experts that are well-known worldwide who are currently working in chemical sensor technologies and to provide an online forum for the presention and discussion of new results. Throughout this event, topics of interest included, but were not limited to, the following: electrochemical devices and sensors; optical chemical sensors; mass-sensitive sensors; materials for chemical sensing; nano- and micro-technologies for sensing; chemical assays and validation; chemical sensor applications; analytical methods; gas sensors and apparatuses; electronic noses; electronic tongues; microfluidic devices; lab-on-a-chip; single-molecule sensing; nanosensors; and medico-diagnostic testing

    2014 Abstract Book

    Get PDF

    Roadmap on energy harvesting materials

    Get PDF
    Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere

    Improving the performance of gas sensor systems with advanced data evaluation, operation, and calibration methods

    Get PDF
    In order to facilitate the widespread use of gas sensors, some challenges must still be overcome. Many of those are related to the reliable quantification of ultra-low concentrations of specific compounds in a background of other gases. This thesis focuses on three important items in the measurement chain: sensor material and operating modes, evaluation of the resulting data, and test gas generation for efficient sensor calibration. New operating modes and materials for gas-sensitive field-effect transistors have been investigated. Tungsten trioxide as gate oxide can improve the selectivity to hazardous volatile organic compounds like naphthalene even in a strong and variable ethanol background. The influence of gate bias and ultraviolet light has been studied with respect to the transport of oxygen anions on the sensor surface and was used to improve classification and quantification of different gases. DAV3E, an internationally recognized MATLAB-based toolbox for the evaluation of cyclic sensor data, has been developed and published as opensource. It provides a user-friendly graphical interface and specially tailored algorithms from multivariate statistics. The laboratory tests conducted during this project have been extended with an interlaboratory study and a field test, both yielding valuable insights for future, more complex sensor calibration. A novel, efficient calibration approach has been proposed and evaluated with ten different gas sensor systems.Vor der weitverbreiteten Nutzung von Gassensoren stehen noch einige Herausforderungen, insbesondere die zuverlässige Messung ultrakleiner Konzentrationen bestimmter Substanzen vor einem Hintergrund anderer Gase. Diese Arbeit konzentriert sich auf drei wichtige Glieder der erforderlichen Messkette: Material und Betriebsweise von Sensoren, Auswertung der anfallenden Daten sowie Generierung von Testgasen zur effizienten Kalibrierung. Neue Betriebsmodi und Materialien für gassensitive Feldeffekttransistoren wurden getestet. Wolframtrioxid kann als Gateoxid die Selektivität für flüchtige organische Verbindungen wie Naphthalin in einem variierenden Ethanolhintergrund verbessern. Der Einfluss von Gate-Bias und ultravioletter Strahlung auf die Bewegung von Sauerstoffionen auf der Oberfläche wurde untersucht und genutzt, um die Klassifizierung und Quantifizierung von Gasen zu verbessern. Eine international anerkannte MATLAB-Toolbox zur Auswertung zyklischer Sensordaten, DAV3E, wurde entwickelt und als open source veröffentlicht. Sie stellt eine nutzerfreundliche Oberfläche und speziell angepasste Algorithmen der multivariaten Statistik zur Verfügung. Die Laborexperimente wurden ergänzt durch vergleichende Messungen in zwei unabhängigen Laboren und einen Feldtest, womit wertvolle Erkenntnisse für die künftig notwendige, komplexe Kalibrierung von Sensoren gewonnen wurden. Ein neuartiger, effizienter Kalibrieransatz wurde vorgestellt und mit zehn unterschiedlichen Sensorsystemen evaluiert

    A MoS<sub>2</sub> Nanoflakes-Based LC Wireless Passive Humidity Sensor

    No full text
    In this study, an LC wireless passive humidity sensor based on MoS2 nanoflakes was proposed. The LC wireless passive humidity sensor was optimized by performing HFSS simulations and fabricated via a screen-printing technique. The MoS2 nanoflakes were characterized by laser scanning confocal microcopy, scanning electron microscope, and X-ray diffraction. The measurements show the sensor can operate stably for a long time with a hysteresis of 4% RH (relative humidity) in 10&#8315;95% RH. At low humidity environment (10&#8315;60% RH), the sensitivity of the as-prepared humidity sensor is 2.79 kHz/% RH, and a sensitivity of 76.04 kHz/% RH was realized in a high humidity environment (60&#8315;95% RH). In this regard, the sensing mechanism was discussed in the scope of proton transfer theory. The test results also indicate that the response time and recovery time of the prepared sensor are 10 s, 15 s, respectively and between 15~40 &#176;C the sensitivity of sensor was not temperature-dependent in the range of 10~80% RH. In addition, the sensor shows less sensitivity to temperature in the 15&#8315;25 &#176;C range at 90% RH. All of these experimental results show that the prepared LC wireless passive humidity sensor can stably monitor the rapidly changing humidity in a sealed and narrow environment for a long time

    ALIPHATIC SILICA‐EPOXY SYSTEMS CONTAINING DOPO‐BASED FLAME RETARDANTS, BIO‐WASTES, AND OTHER SYNERGISTS

    Get PDF
    Most industrial applications require polymer‐based materials showing excellent fire performances to satisfy stringent requirements. No‐dripping and self‐extinguishing hybrid silica‐epoxy composites can be prepared by combining tailored sol‐gel synthesis strategies with DOPO‐based flame retardants, bio‐wastes, and other synergists. This approach allows for achieving V‐0 rating in UL‐94 vertical flame spread tests, even using a sustainable route, aliphatic amine as hardener, and low P loadings

    MC 2019 Berlin Microscopy Conference - Abstracts

    Get PDF
    Das Dokument enthält die Kurzfassungen der Beiträge aller Teilnehmer an der Mikroskopiekonferenz "MC 2019", die vom 01. bis 05.09.2019, in Berlin stattfand
    corecore