The Experts below are selected from a list of 219 Experts worldwide ranked by ideXlab platform
K.a.r. Mitchell - One of the best experts on this subject based on the ideXlab platform.
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XPS studies of the stability and reactivity of thin films of oxidized zirconium
Applied Surface Science, 1993Co-Authors: Y.m. Wang, P. C. Wong, K.a.r. MitchellAbstract:Abstract X-ray photoelectron spectroscopy (XPS) has been used to characterize thin films formed by the deposition of zirconium on to gold foil. With deposition rates of the order of 1 A min-1, in the presence of an atmosphere of 10-9 mbar H2O, the film has an outer region of ZrO2 and inner regions of a Lower Oxidation State material, ZrOx, and Zr-Au alloy. Initially both ZrOx and Zr-Au alloy are oxidized by either H2O or O2 at 300°C, although this process is hindered as the ZrO2 layer gets thicker. However, even with the protective oxide layer, heating in 5 x 10-7 mbar D2 (with a partial pressure of 10-9 mbar H2O) can convert ZrOx to ZrO2, a reaction apparently facilitated by migrating D atoms.
Krystian Roleder - One of the best experts on this subject based on the ideXlab platform.
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Weak ferromagnetic response in PbZr1−xTixO3 single crystals
Journal of Materials Chemistry C, 2019Co-Authors: Iwona Lazar, M. Oboz, Jerzy Kubacki, Andrzej Majchrowski, Julita Piecha, D. Kajewski, Krystian RolederAbstract:For the first time, a weak ferromagnetic hysteresis loop at room temperature has been observed in PbZr1−xTixO3 (PZT) single crystals. The occurrence of these properties has been related to the presence of oxygen vacancies and/or Lower Oxidation State of titanium. This proves that ferroelectric and ferromagnetic properties can occur simultaneously in this “famous” piezoelectric perovskite without any magnetic dopant.
Beatriz Roldan Cuenya - One of the best experts on this subject based on the ideXlab platform.
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the role of the copper Oxidation State in the electrocatalytic reduction of co2 into valuable hydrocarbons
ACS Sustainable Chemistry & Engineering, 2019Co-Authors: Juanjesus Velascovelez, Travis Jones, Emilia A Carbonio, Rosa Arrigo, Yucheng Huang, Chungli Dong, Jinming Chen, Peter Strasser, Beatriz Roldan CuenyaAbstract:Redox-active copper catalysts with accurately prepared Oxidation States (Cu0, Cu+, and Cu2+) and high selectivity to C2 hydrocarbon formation, from electrocatalytic cathodic reduction of CO2, were fabricated and characterized. The electrochemically prepared copper-redox electro-cathodes yield higher activity for the production of hydrocarbons at Lower Oxidation State. By combining advanced X-ray spectroscopy and in situ microreactors, it was possible to unambiguously reveal the variation in the complex electronic structure that the catalysts undergo at different stages (i.e., during fabrication and electrocatalytic reactions). It was found that the surface, subsurface, and bulk properties of the electrochemically prepared catalysts are dominated by the formation of copper carbonates on the surface of cupric-like oxides, which prompts catalyst deactivation by restraining effective charge transport. Furthermore, the formation of reduced or partially reduced copper catalysts yields the key dissociative proto...
Robert Schlögl - One of the best experts on this subject based on the ideXlab platform.
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Probing a Redox Behavior of TiO2/SBA-15 Supported VxOy Catalyst Using an Electron Beam in a 200 kV Transmission Electron Microscope
The Journal of Physical Chemistry C, 2011Co-Authors: Wei Zhang, Bingsen Zhang, Till Wolfram, Lidong Shao, Robert SchlöglAbstract:Supported vanadium oxides are becoming the model catalysts for. numerous selective Oxidation reactions. To exploit redox chemistry of well-known titania-supported vanadia is currently one of the most fascinating topics. Herein, by applying in situ electron energy-loss spectroscopy, we succeeded in stimulating a new redox reaction in a routine transmission electron microscope; the electron beam can boost further Oxidation from an amorphous Lower-Oxidation-State vanadia to maximal V(2)O(5) with an expense of oxygen from its support of TiO(2) to be reduced. Our findings could be extended into a new strategy: through utilizing an electron beam, and probing the redox chemistry between catalysts and their support in a wide class of heterogeneous catalyst systems, such as various oxide/oxide, metal/oxide, and oxide/metal catalysts.
Y.m. Wang - One of the best experts on this subject based on the ideXlab platform.
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XPS studies of the stability and reactivity of thin films of oxidized zirconium
Applied Surface Science, 1993Co-Authors: Y.m. Wang, P. C. Wong, K.a.r. MitchellAbstract:Abstract X-ray photoelectron spectroscopy (XPS) has been used to characterize thin films formed by the deposition of zirconium on to gold foil. With deposition rates of the order of 1 A min-1, in the presence of an atmosphere of 10-9 mbar H2O, the film has an outer region of ZrO2 and inner regions of a Lower Oxidation State material, ZrOx, and Zr-Au alloy. Initially both ZrOx and Zr-Au alloy are oxidized by either H2O or O2 at 300°C, although this process is hindered as the ZrO2 layer gets thicker. However, even with the protective oxide layer, heating in 5 x 10-7 mbar D2 (with a partial pressure of 10-9 mbar H2O) can convert ZrOx to ZrO2, a reaction apparently facilitated by migrating D atoms.
