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Nanoscaled polypyrrole for sensing gaseous analytes and volatile organic compounds
Šetka, Milena ; Dian,, Juraj (oponent) ; Mandayo, Gemma García (oponent) ; Drbohlavová, Jana (vedoucí práce)
Polypyrrole (PPy) is a hetero-cyclic conductive polymer (CPs) with chemical structure based on the existence of conjugated electrons between alternating single and double bond system. This polymer has occupied the attention of many scientists from different research disciplines due to its outstanding properties such as good electrical conductivity, relatively high environmental stability, and facile and diversified synthesis methods. The aim of this research was to study the sensing behavior of PPy. Therefore, the gas sensing performances of PPy nanostructures were verified to ‘gas molecules of high importance’ including acetone, ammonia, ethanol, ethylene and toluene. In this work, PPy in the form of nanorods (NRs) and nanoparticles (NPs) was prepared using electrochemical and chemical synthesis approaches, respectively. Additionally, the modified PPy structures were developed by functionalization of PPy NPs with catalytic particles of gold (Au), silver (Ag) and cadmium-telluride (CdTe). Many complementary analytical techniques (microscopic and spectroscopic) were used for the investigation of morphology, composition and structure of the synthesized materials. Moreover, spectroscopy techniques such as Raman and X-Ray Photoelectron Spectroscopy (XPS) were employed for in-situ gas sensing tests, which confirmed the potential of PPy NRs and PPy NPs to be used as gas sensitive materials. In order to developed the gas sensor device, the PPy based materials were integrated into chemo-resistive and Love mode surface acoustic wave (L-SAW) transducing platforms. The gas sensing test of chemo-resistive sensors based on PPy NRs revealed negligible response to nitrogen dioxide and ammonia due to complicate architecture of those sensors. The measuring of response of non-modified and modified PPy NPs chemo-resistive sensors was complex due to their extremely high resistance in G range. However, multi-guiding L-SAW sensors based on bare PPy NPs and modified with Au NPs and Ag NPs, and CdTe quantum dots (QDs) manifested the response to low concentration of all tested target gas molecules including ammonia, acetone, ethanol, ethyleen and toluene at room temperature (RT). Generally, the L-SAW sensors with modified sensing layers established enhanced sensing performances over non-modified sensors. The performance of the L-SAW sensor primarily depends on the operating frequency and the choose of sensitive layer in the active region of the sensor. Thus, among the tested sensing layers for the target gases, modified PPy layer with Ag NPs and/or Au NPs can be selected as the best option for the detection of acetone. The developed PPy based L-SAW sensors are simple and cost effective devices with improved sensing properties such as high sensitivity and low limit of detection (LOD) which make them potential candidates in future systems for air quality control, food quality control or disease diagnosis via exhaled breath.
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Nové materiály pro Li-iontové baterie pracující na principu konverze
Petr, Jakub ; Straková Fedorková, Andrea (oponent) ; Sedlaříková, Marie (vedoucí práce)
Tato diplomová práce se zabývá novými materiály pro lithno – iontové baterie. Zkoumanými vzorky jsou zde jak interkalační, tak také konverzní materiály. V teoretické části je věnována pozornost skladbě článků, jejich výhodám i nevýhodám oproti jiným sekundárním bateriím. Dále jsou zde popsány jednotlivé materiály pro jejich výrobu. V praktické části jsou popsány přípravy katodových materiálů s jejich následným otestováním pomocí skenovaní elektronové mikroskopie a termogravimetrické analýzy. V samotném závěru diplomové práce jsou jednotlivé materiály zhodnoceny a porovnány mezi sebou.
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Nanoscaled polypyrrole for sensing gaseous analytes and volatile organic compounds
Šetka, Milena ; Dian,, Juraj (oponent) ; Mandayo, Gemma García (oponent) ; Drbohlavová, Jana (vedoucí práce)
Polypyrrole (PPy) is a hetero-cyclic conductive polymer (CPs) with chemical structure based on the existence of conjugated electrons between alternating single and double bond system. This polymer has occupied the attention of many scientists from different research disciplines due to its outstanding properties such as good electrical conductivity, relatively high environmental stability, and facile and diversified synthesis methods. The aim of this research was to study the sensing behavior of PPy. Therefore, the gas sensing performances of PPy nanostructures were verified to ‘gas molecules of high importance’ including acetone, ammonia, ethanol, ethylene and toluene. In this work, PPy in the form of nanorods (NRs) and nanoparticles (NPs) was prepared using electrochemical and chemical synthesis approaches, respectively. Additionally, the modified PPy structures were developed by functionalization of PPy NPs with catalytic particles of gold (Au), silver (Ag) and cadmium-telluride (CdTe). Many complementary analytical techniques (microscopic and spectroscopic) were used for the investigation of morphology, composition and structure of the synthesized materials. Moreover, spectroscopy techniques such as Raman and X-Ray Photoelectron Spectroscopy (XPS) were employed for in-situ gas sensing tests, which confirmed the potential of PPy NRs and PPy NPs to be used as gas sensitive materials. In order to developed the gas sensor device, the PPy based materials were integrated into chemo-resistive and Love mode surface acoustic wave (L-SAW) transducing platforms. The gas sensing test of chemo-resistive sensors based on PPy NRs revealed negligible response to nitrogen dioxide and ammonia due to complicate architecture of those sensors. The measuring of response of non-modified and modified PPy NPs chemo-resistive sensors was complex due to their extremely high resistance in G range. However, multi-guiding L-SAW sensors based on bare PPy NPs and modified with Au NPs and Ag NPs, and CdTe quantum dots (QDs) manifested the response to low concentration of all tested target gas molecules including ammonia, acetone, ethanol, ethyleen and toluene at room temperature (RT). Generally, the L-SAW sensors with modified sensing layers established enhanced sensing performances over non-modified sensors. The performance of the L-SAW sensor primarily depends on the operating frequency and the choose of sensitive layer in the active region of the sensor. Thus, among the tested sensing layers for the target gases, modified PPy layer with Ag NPs and/or Au NPs can be selected as the best option for the detection of acetone. The developed PPy based L-SAW sensors are simple and cost effective devices with improved sensing properties such as high sensitivity and low limit of detection (LOD) which make them potential candidates in future systems for air quality control, food quality control or disease diagnosis via exhaled breath.
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Nové materiály pro Li-iontové baterie pracující na principu konverze
Petr, Jakub ; Straková Fedorková, Andrea (oponent) ; Sedlaříková, Marie (vedoucí práce)
Tato diplomová práce se zabývá novými materiály pro lithno – iontové baterie. Zkoumanými vzorky jsou zde jak interkalační, tak také konverzní materiály. V teoretické části je věnována pozornost skladbě článků, jejich výhodám i nevýhodám oproti jiným sekundárním bateriím. Dále jsou zde popsány jednotlivé materiály pro jejich výrobu. V praktické části jsou popsány přípravy katodových materiálů s jejich následným otestováním pomocí skenovaní elektronové mikroskopie a termogravimetrické analýzy. V samotném závěru diplomové práce jsou jednotlivé materiály zhodnoceny a porovnány mezi sebou.
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Nové materiály pro Li-iontové baterie pracující na principu konverze
Petr, Jakub ; Straková Fedorková, Andrea (oponent) ; Sedlaříková, Marie (vedoucí práce)
Tato diplomová práce se zabývá novými materiály pro lithno – iontové baterie. Zkoumanými vzorky jsou zde jak interkalační, tak také konverzní materiály. V teoretické části je věnována pozornost skladbě článků, jejich výhodám i nevýhodám oproti jiným sekundárním bateriím. Dále jsou zde popsány jednotlivé materiály pro jejich výrobu. V praktické části jsou popsány přípravy katodových materiálů s jejich následným otestováním pomocí skenovaní elektronové mikroskopie a termogravimetrické analýzy. V samotném závěru diplomové práce jsou jednotlivé materiály zhodnoceny a porovnány mezi sebou.
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