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1.
Orellana M Arriola P Del Río R Schrebler R Cordova R Scholz F Kahlert H 《The journal of physical chemistry. B》2005,109(32):15483-15488
During the electrochemical oxidation of Prussian blue (PB) to Prussian yellow (PY), an electrocatalytic oxygen production proceeds at the electrode when aqueous electrolyte solutions are used. The formed oxygen is scavenged by the PY, probably by absorption, and it is consumed during the electrochemical reduction of PY to PB by a heterogeneous chemical reaction of PB with oxygen to PY and hydrogen peroxide. Because of this catalytic regeneration of PY, it is impossible to determine the amount of low-spin iron by chronocoulometry using a potential program in which PB is first oxidized to PY and then the charge is measured to reduce PY to PB. The latter charge is biased by the electrocatalytic PY regeneration. 相似文献
2.
Grez P Celedón C Molinari A Oliva A Orellana M Schrebler R del Río R Córdova R 《The journal of physical chemistry. B》2005,109(48):22920-22927
The interaction of the ethyl xanthate (EX) anion with a copper electrode in a borate buffer solution, pH 9.2, has been investigated by cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), electrochemical impedance spectroscopy (EIS), and measurements of contact angle (CA) under controlled potential. The results obtained allow establishing that, in the potential range from -0.80 and -0.60 V, two parallel reactions were characterized. These reactions were the ethyl xanthate electroadsorption and the hydrogen evolution reaction (HER). This last reaction has not been described by previous authors. Besides, the EIS measurements show that the mechanism of the HER on copper electrodes is not affected by the presence of a ethyl xanthate species. The EQCM study shows that in the electrodesorption process the departure of each ethyl xanthate species from the copper electrode is accompanied with the simultaneous entry of four to five water molecules. This fact is in accordance with the number of copper atoms involved in the adsorption of one ethyl xanthate species. 相似文献
3.
Navarrete-Astorga Elena Rodríguez-Moreno Jorge Dalchiele Enrique A. Schrebler Ricardo Leyton Patricio Ramos-Barrado José R. Martín Francisco 《Journal of Solid State Electrochemistry》2017,21(5):1431-1444
Journal of Solid State Electrochemistry - A feasibility study of the synthesis of gel polymer electrolytes based in methyl methacrylate (MMA) and 1-vinyl-2-pyrrolidone (VP) using [HEMIm][BF4] as... 相似文献
4.
5.
Alfonso Oliva Aurora Molinari Jean Angulo Ricardo Schrebler Humberto Gómez Ricardo Córdova 《合成通讯》2013,43(23):4353-4360
The electrooxidation of 1-phenyl-3-methyl-4-butyldithiocarboxylate-5-pyrazolone 1 has been studied in ethanol/water solution, using a glassy carbon electrode surface. The electrochemical and spectroscopic data are in agreement with a bis-ketenedithioacetal disulphide compound 2 as the only product of the reaction. 相似文献
6.
The polarographic behaviour of Cu, Pb, Zn, Mn, Cd, Ni and Bi diethyldithiocarbamates in benzene-methanol media was examined. A separation method was developed which allowed polarographic determination of all of these complexes without mutual interferences. Good precision and accuracy were obtained in the analysis of artificial mixtures and standard samples. 相似文献
7.
Velásquez P Leinen D Pascual J Ramos-Barrado JR Grez P Gómez H Schrebler R Del Río R Córdova R 《The journal of physical chemistry. B》2005,109(11):4977-4988
Electrodic surfaces of natural chalcopyrite and natural pyrite minerals (El Teniente mine, Chile) have been studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy including microanalysis (SEM/EDX). For comparison, fractured and polished mineral surfaces were also studied by XPS. In both electrodes, the formation of Fe(III) species containing oxygen were detected and Cu(II) species containing oxygen were additionally detected for chalcopyrite at advanced oxidation states. The presence of Cu(II) species containing oxygen was not detected by XPS for the initial oxidation states of the chalcopyrite. For pyrite, the present results do not allow confirmation of the presence of polysulfurs such as have been previously proposed. In both minerals, the measurements of SEM and EDX show relevant alterations in the respective surfaces when different potential values were applied. The chalcopyrite surface shows the formation of protrusions with a high concentration of oxygen. The pyrite surface shows a layer of modified material with high oxygen content. The modifications detected by XPS, SEM, and EDX allowed the explanation of the complexity of the equivalent circuit used to simulate the experimental EIS data. At high oxidation states, both minerals showed a pseudoinductive loop in the equivalent circuit, which was due to the active electrodissolution of the minerals which takes place through a surface film previously formed. 相似文献
8.
M. Orellana L. Ballesteros R. Del Río P. Grez R. Schrebler R. Córdova 《Journal of Solid State Electrochemistry》2009,13(8):1303-1308
In the present work, an arrangement of polystyrene (PS) spheres was employed as a pattern for the electrodeposition of nanostructured
Prussian blue (PB). The pattern of PS spheres was formed on Indium tin oxide (ITO) glass substrate. The ITO substrate modified
by the PS spheres was used as a working electrode for the electrosynthesis of PB. A macroporous PB film constituted by nanoparticles
of the compound was obtained after the dissolution of the spheres and was characterized by voltammetric and atomic force microscopy
techniques. The electrocatalytic properties of this material were tested in the electrooxidation of hydrazine. 相似文献
9.
Humberto Gomez Gonzalo Riveros Daniel Ramirez Rodrigo Henriquez Ricardo Schrebler Ricardo Marotti Enrique Dalchiele 《Journal of Solid State Electrochemistry》2012,16(1):197-204
ZnO nanowire arrays were grown by potentiostatic cathodic electrodeposition on aluminum anodic oxide template (AAO) from dimethyl
sulfoxide (DMSO) solutions containing zinc chloride and molecular oxygen as precursors. The nanowires presented high aspect
ratio and exhibited a very high crystallinity with a wurtzite crystal structure with preferential orientation along the (0001)
crystallographic axis. Chronoamperometric experiments were performed on gold bulk electrodes in order to model this preferential
mode growth of ZnO nanowires, which has not been previously reported for similar precursors in DMSO solution. The analysis
of the corresponding chronoamperograms revealed that chloride ions influence the oxide nucleation and growth mechanism. It
was found that in the absence of KCl as a supporting electrolyte, the data fitted an instantaneous three-dimensional diffusion-controlled
(IN-3D)diff nucleation and growth mechanism (NGM). The presence of KCl, instead favored a progressive three-dimensional (PN-3D)diff NGM. With these results, a model for the more complex nanowire’s growth inside the pores of the AAO template is proposed. 相似文献
10.
Muñoz EC Schrebler RS Cury PK Suarez CA Córdova RA Gómez CH Marotti RE Dalchiele EA 《The journal of physical chemistry. B》2006,110(42):21109-21117
In this study, we examined the influence of illumination and the presence of poly(ethylene oxide) (PEO) as an additive for the copper electrodeposition process onto n-Si(100). The study was carried out by means of cyclic voltammetry (CV) and the potential steps method, from which the corresponding nucleation and growth mechanism (NGM) were determined. Likewise, a morphologic analysis of the deposits obtained at different potential values by means of atomic force microscopy (AFM) was carried out. In a first stage, Mott-Schottky measurements so as to characterize the energetics of the semiconductor/electrolyte interface were made. Also, parallel capacity measurements were carried out in order to determine the surface state density of the substrate. It was found that when PEO concentration is increased, the number of these surface states decreases. The CV results indicated that the presence of PEO inhibits the photoelectrochemical reaction of oxide formation on the surface of the semiconductor. This allows a decrease in the overpotential associated with the electrodeposition process. The analysis of the j/t transients shows that the NGM corresponds to progressive three-dimensional (3D) diffusional controlled (PN3D(Diff)), which was confirmed by the AFM technique. Neither illumination nor the presence of PEO changes the mechanisms. Their influence is in that they diminish the size of the nuclei and the speed with which these are formed, which produces a more homogeneous electrodeposit. 相似文献