94 research outputs found

    Equilibrium Behavior for Transition Metal Ionic Species in Liquid Phase Deposition Reaction

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    We tried to clarify to the deposition mechanism by applying the 11B and 19F NMR analyses to the LPD reaction solutions for the preparing titanium oxide films with various reaction conditions. Moreover, the optimum conditions of the syntheses of 3d transition metal oxide thin films were investigated by con-trolling pH and the concentration of reacting species. In the reaction of TiO2 deposition, TiF62- do not re-lease all F- ions, namely, the existence of hydrolysis intermediate species (TiFx(OH)y(H2O)6-x-y(4-x-y)) which could not be detected by 19F NMR because of the rapid ligand exchange in the LPD reaction solu-tions. In the reaction of Cr2O3 deposition, the optimization of the LPD reaction can be carried out by the controlling of the concentrations of reaction species and pH. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3522

    Destabilized Passivation Layer on Magnesium-Based Intermetallics as Potential Anode Active Materials for Magnesium Ion Batteries

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    Passivation of magnesium metal anode is one of the critical challenges for the development of magnesium batteries. Here we investigated the passivation process of an intermetallic anode: Mg3Bi2 synthesized by solid-state and thin film process. The Mg3Bi2 composite electrode shows excellent reversibility in magnesium bis(trifluoromethansulfonylamide) dissolved in acetonitrile, while Mg3Sb2, which has same crystal structure and similar chemical properties, is electrochemically inactive. We also fabricated the Mg3Bi2 thin film electrodes, which show reversibility with low overpotential not only in the acetonitrile solution but also glyme-based solutions. Surface layer corresponding to the decomposed TFSA anion is slightly suppressed in the case of the Mg3Bi2 thin film electrode, compared with Mg metal. Comparative study of hydrolysis process of the Mg3Bi2 and the Mg3Sb2 suggests that the both intermetallic anodes are not completely passivated. The bond valence sum mapping of the Mg3Bi2 indicates that the fast Mg2+ diffusion pathway between 2d tetrahedral sites is formed. The electrochemical properties of the Mg3Bi2 anode is mainly due to the less passivation surface with the fast Mg2+ diffusion pathways

    History of ECSJ Awards and Introduction of Award Winners in 2021

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    The Electrochemical Society of Japan (ECSJ) has been publishing comprehensive papers related to the achievements of researchers who are awarded by ECSJ annually since 2014. The origin of the society awards, we can see that they began as Tanahashi Paper Award. In order to promote the use of this journal an academic and industrial outcomes from the activity of ECSJ members, the editorial board would like to introduce the society awards and the awardees’ achievements as an award-winning feature article

    Applications of Ni-Al Layered Double Hydroxide as Oxygen Evolution Reaction Catalysts Synthesized by Liquid Phase Deposition Process

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    The Ni-Al layered double hydroxide materials with high crystallinity were synthesized by the room-temperature liquid process and applied as oxygen evolution reaction (OER) catalysts. It is interesting to note that the OER activity was found to be relatively high in comparison with the Ni-based materials. In addition, the structural analyses and the effects of interlayer anion specie on the OER activity were also evaluated. It was found that the changes in the interlayer anion species from F− to OH− resulted in the enhancement of the OER activity. The maintained chemical compositions and crystallinity after the electrochemical measurements were also observed through the X-ray analyses. The present work provides the insights about the possibility of the well-defined structures as the electrodes which were prepared by the unique liquid phase process

    Removal of Surface Scale from Titanium Metal by Etching with HF–HNO<sub>3</sub> Mixed Acid

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    Etching of commercial pure titanium (CP-Ti) covered with metal oxide scale transferred to the surface from roller mills like those used for steel refining was investigated based on potentiodynamic polarization measurements and quantitative analysis of metal dissolved in HF or HF–HNO3. CP-Ti prepared by an industrial titanium supplier, titanium plate with scale (S-Ti), and annealed and pickled titanium (AP-Ti) were examined. The titanium substrate under the scale layer immediately dissolved in HF solution of concentration 1.0 mol·L−1. The etching behavior was examined in detail by electrochemical analysis in dilute HF. At HF concentrations less than 0.1 mol·L−1, the oxidized layer of S-Ti remained. X-ray photoelectron spectroscopy was used to identify the major components of the S-Ti surface, such as copper and iron impurities. In HF–HNO3 solution, the scale was removed slowly, even at high HF concentrations. The amounts of dissolved titanium indicated that calcium on the titanium metal surface increased the etching rate, and the minimum apparent activation energies, ΔEa, of the etching reactions were observed at a concentration of 0.0316 mol·L−1 HF aq. for S-Ti and AP-Ti because of the trade-off between the HF activity and ionic dissociation. Etching of CP-Ti began with dissolution of the passive layer of titanium; corrosion of S-Ti was the result of destruction of the titanium oxide layer by F− and dissolution of the pure titanium substrate. The etching behavior of S-Ti at high HF concentrations suggested that scale peeling by substrate etching is a promising method for efficient scale removal. The HNO3 concentration had little effect on the anodic polarization curves of CP-Ti. This is attributed to the presence of a stable oxide layer on the titanium metal. We investigated the details of the S-Ti etching mechanism in HF–HNO3 for efficient scale removal
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