The Experts below are selected from a list of 6978 Experts worldwide ranked by ideXlab platform
Beomgyun Jeong - One of the best experts on this subject based on the ideXlab platform.
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Pyrolytic Carbon infiltrated nanoporous alumina reducing contact resistance of aluminum/Carbon interface
Electrochimica Acta, 2013Co-Authors: Beomgyun JeongAbstract:Abstract We fabricated a highly conductive Pyrolytic Carbon layer that penetrates into nanoporous alumina channels and that strongly adheres to an aluminum (Al) current collector in order to reduce the contact resistance at the interface between a Carbon active material and an Al current collector. The fabrication method includes the following processes: (i) Al anodization, (ii) alumina etching, (iii) nickel seed layer deposition on the alumina surface, and (iv) chemical vapor deposition of Pyrolytic Carbon grown by the catalytic nickel layer. From SEM and EDX analyses, we confirmed that the Pyrolytic Carbon could be uniformly placed into an alumina nanoporous template on the Al substrate. Based on measurements of the transverse resistance and electrochemical capacitor tests, the fabricated composite layer of Pyrolytic Carbon and nanoporous alumina significantly reduced contact resistance of Al/Carbon interface due to the highly conductive Pyrolytic Carbon formed through the nanoporous alumina on the Al surface.
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Pyrolytic Carbon infiltrated nanoporous alumina reducing contact resistance of aluminum/Carbon interface
Electrochimica Acta, 2013Co-Authors: Beomgyun JeongAbstract:Abstract We fabricated a highly conductive Pyrolytic Carbon layer that penetrates into nanoporous alumina channels and that strongly adheres to an aluminum (Al) current collector in order to reduce the contact resistance at the interface between a Carbon active material and an Al current collector. The fabrication method includes the following processes: (i) Al anodization, (ii) alumina etching, (iii) nickel seed layer deposition on the alumina surface, and (iv) chemical vapor deposition of Pyrolytic Carbon grown by the catalytic nickel layer. From SEM and EDX analyses, we confirmed that the Pyrolytic Carbon could be uniformly placed into an alumina nanoporous template on the Al substrate. Based on measurements of the transverse resistance and electrochemical capacitor tests, the fabricated composite layer of Pyrolytic Carbon and nanoporous alumina significantly reduced contact resistance of Al/Carbon interface due to the highly conductive Pyrolytic Carbon formed through the nanoporous alumina on the Al surface.
G. Wenders - One of the best experts on this subject based on the ideXlab platform.
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Pyrolytic Carbon film electrodes
Analytical and bioanalytical chemistry, 1996Co-Authors: J. P. Surmann, G. WendersAbstract:Home-made Pyrolytic Carbon film electrodes (PCFE) were tested in voltammetric experiments. Different drugs were analyzed by differential pulse voltammetry. In many cases the reproducibility of the signals is as satisfactory as by using glassy Carbon electrodes (GCE). The cleaning procedure is very easy to accomplish by wiping off the electrode surface with a paper tissue dipped into methanol. The peak- to residual current rate is much better at the PCFE than at the GCE. Therefore the detection limit is lowered at the former.
J. P. Surmann - One of the best experts on this subject based on the ideXlab platform.
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Pyrolytic Carbon film electrodes
Analytical and bioanalytical chemistry, 1996Co-Authors: J. P. Surmann, G. WendersAbstract:Home-made Pyrolytic Carbon film electrodes (PCFE) were tested in voltammetric experiments. Different drugs were analyzed by differential pulse voltammetry. In many cases the reproducibility of the signals is as satisfactory as by using glassy Carbon electrodes (GCE). The cleaning procedure is very easy to accomplish by wiping off the electrode surface with a paper tissue dipped into methanol. The peak- to residual current rate is much better at the PCFE than at the GCE. Therefore the detection limit is lowered at the former.
Boris Reznik - One of the best experts on this subject based on the ideXlab platform.
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Chemistry and kinetics of chemical vapor deposition of Pyrolytic Carbon from ethanol
Proceedings of the Combustion Institute, 2011Co-Authors: S. Zhang, Boris Reznik, Sven Lichtenberg, G. Schoch, Olaf DeutschmannAbstract:Synthesis of Pyrolytic Carbon as a matrix for Carbon fiber reinforced Carbon composites by chemical vapor infiltration (CVI) is studied experimentally and numerically using the oxygen-containing precursor ethanol. The effects of residence time on microstructure and deposition rate of Pyrolytic Carbon are investigated. A short residence time is found to favor the formation of high-textured Pyrolytic Carbon. The evolutions of microstructure and deposition rate of Pyrolytic Carbon are compared with those of Carbon deposited from methane. Compared to methane, ethanol exhibits a much higher deposition rate of Pyrolytic Carbon with similar microstructures. Pyrolysis of ethanol is modeled using a two-dimensional flow model coupled with a detailed gas-phase reaction mechanism involving 261 species taking part in 1177 reversible reactions. Reaction rate analysis reveals that C3-hydroCarbons are the most important intermediate species contributing to the maturation of gas-phase composition. A comparison of the kinetic predictions with equilibrium calculations demonstrates that the CVD reactor applied is operated far away from equilibrium.
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Synthesis of Pyrolytic Carbon Composites Using Ethanol As Precursor
Industrial & Engineering Chemistry Research, 2010Co-Authors: Shou Yang Zhang, Boris Reznik, Sven Lichtenberg, Olaf DeutschmannAbstract:Chemical vapor infiltration and deposition of Carbon fiber bundles are applied to synthesize Pyrolytic Carbon composites using the oxygen-containing precursor ethanol. The influence of the temperature (1373 and 1423 K) and pressure (1−7 Pa) on the microstructure and the deposition rate of Pyrolytic Carbon are experimentally studied. Higher partial pressures of ethanol are demonstrated to favor the growth of highly ordered graphene-like pyroCarbon, whereas lower partial pressures help to suppress the Carbon texture transition. The gas-phase composition and reaction kinetics are numerically analyzed on the basis of a reacting flow model with a detailed reaction mechanism. Methane and C2 species are shown to be the dominant intermediate species of ethanol pyrolysis. According to the simulation, a large amount of CH3 radicals is produced, which explains the fact that the Pyrolytic Carbon from ethanol exhibits a texture similar to the one produced with CH4 as precursor.
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Interfacial adhesion and friction of Pyrolytic Carbon thin films on silicon substrates
Journal of Materials Research, 2008Co-Authors: N. Deyneka-dupriez, Th. Schimmel, Andreas Pfrang, Boris Reznik, Ulrich Herr, H-j. Fecht, Dagmar GerthsenAbstract:Frictional behavior and interfacial adhesion of differently textured Pyrolytic Carbon layers on Si substrate were investigated by indentation and scratch testing. A large amount of elastic recovery and a low coefficient of friction (μ = 0.05 to 0.09) were observed. Elastic/plastic and frictional behaviors of the coatings are strongly influenced by the microstructure of the Pyrolytic Carbon films, especially by the texture. The critical load at which the first abrupt increase in the normal displacement occurs was used to characterize interfacial adhesive strength. A Pyrolytic Carbon film deposited at higher residence time from a gas mixture containing 3% oxygen exhibited higher critical loads than film deposited at lower residence time without oxygen. The results can be understood if one assumes that the gas phase composition during deposition significantly influences the bonding strength at the interface. Failure mechanisms are discussed for both types of films.
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An improved method for angular-resolved characterization of the optical anisotropy of Pyrolytic Carbon.
Journal of Microscopy, 2006Co-Authors: Boris Reznik, Dagmar Gerthsen, E. G. BortchagovskyAbstract:A description is given of an experimental technique that improves the accuracy of the measurement of light extinctions by polarized light microscopy from deposits of Pyrolytic Carbon. The measurements were performed using a specially developed digital photometric image-analysis procedure providing high spatial and angular resolution of light extinctions over the reflecting optical domains with a high dynamic range of grey levels. The digital image acquisition and data processing are illustrated using circular-shaped Pyrolytic Carbon matrices of infiltrated Carbon fibre felts and planar layers of Pyrolytic graphite. The calculated value of the extinction angle for single crystalline graphite is discussed with respect to the experimental values for Pyrolytic Carbon with different degrees of optical anisotropy. Practical requirements for the accuracy of the method are discussed.
Olaf Deutschmann - One of the best experts on this subject based on the ideXlab platform.
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Chemistry and kinetics of chemical vapor deposition of Pyrolytic Carbon from ethanol
Proceedings of the Combustion Institute, 2011Co-Authors: S. Zhang, Boris Reznik, Sven Lichtenberg, G. Schoch, Olaf DeutschmannAbstract:Synthesis of Pyrolytic Carbon as a matrix for Carbon fiber reinforced Carbon composites by chemical vapor infiltration (CVI) is studied experimentally and numerically using the oxygen-containing precursor ethanol. The effects of residence time on microstructure and deposition rate of Pyrolytic Carbon are investigated. A short residence time is found to favor the formation of high-textured Pyrolytic Carbon. The evolutions of microstructure and deposition rate of Pyrolytic Carbon are compared with those of Carbon deposited from methane. Compared to methane, ethanol exhibits a much higher deposition rate of Pyrolytic Carbon with similar microstructures. Pyrolysis of ethanol is modeled using a two-dimensional flow model coupled with a detailed gas-phase reaction mechanism involving 261 species taking part in 1177 reversible reactions. Reaction rate analysis reveals that C3-hydroCarbons are the most important intermediate species contributing to the maturation of gas-phase composition. A comparison of the kinetic predictions with equilibrium calculations demonstrates that the CVD reactor applied is operated far away from equilibrium.
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Synthesis of Pyrolytic Carbon Composites Using Ethanol As Precursor
Industrial & Engineering Chemistry Research, 2010Co-Authors: Shou Yang Zhang, Boris Reznik, Sven Lichtenberg, Olaf DeutschmannAbstract:Chemical vapor infiltration and deposition of Carbon fiber bundles are applied to synthesize Pyrolytic Carbon composites using the oxygen-containing precursor ethanol. The influence of the temperature (1373 and 1423 K) and pressure (1−7 Pa) on the microstructure and the deposition rate of Pyrolytic Carbon are experimentally studied. Higher partial pressures of ethanol are demonstrated to favor the growth of highly ordered graphene-like pyroCarbon, whereas lower partial pressures help to suppress the Carbon texture transition. The gas-phase composition and reaction kinetics are numerically analyzed on the basis of a reacting flow model with a detailed reaction mechanism. Methane and C2 species are shown to be the dominant intermediate species of ethanol pyrolysis. According to the simulation, a large amount of CH3 radicals is produced, which explains the fact that the Pyrolytic Carbon from ethanol exhibits a texture similar to the one produced with CH4 as precursor.
