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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
2.
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
3.
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
4.
Rojas Víctor López Silvana Cáceres Gustavo Schrebler Ricardo G. Grez Paula Henríquez Rodrigo Ballesteros Luis Navarrete Emilio Herrera Francisco Muñoz Eduardo C. 《Journal of Solid State Electrochemistry》2021,25(4):1131-1138
Journal of Solid State Electrochemistry - In this work, an assembly of FTO/α-Fe2O3/PB|M+ electrolyte|PB/α-Fe2O3/FTO (M+ = Li+, Na+, K+) secondary photocell was done to improve... 相似文献
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Navarrete Emilio Rojas Víctor Romero Mario Román J. Cáceres G. Henríquez Rodrigo Grez Paula Schrebler Ricardo Herrera Francisco Muñoz Eduardo C. 《Journal of Solid State Electrochemistry》2021,25(1):133-140
Journal of Solid State Electrochemistry - Cadmium telluride quantum dots (CdTe-QDs) can be deposited from colloidal solutions on glassy carbon (GC) electrodes potentiostatically. The immobilization... 相似文献
6.
Córdova R López C Orellana M Grez P Schrebler R Del Río R 《The journal of physical chemistry. B》2005,109(8):3212-3221
The electroformation of Cu-Se phases, obtained by selenizing a thin film of copper deposited on the quartz/gold electrode system, was studied with an electrochemical quartz crystal microbalance (EQCM) and by cyclic voltammetry (CV) in an alkaline solution (0.05 M Na(2)B(4)O(7)) containing selenide ion. Potentiodynamic parameters showed that the formation of the initial Cu-Se phases (Cu(2-x)Se/Cu(3)Se(2)) is ruled by an irreversible diffusion controlled mechanism, where a first electron transfer is the rate-determining step. A CV study was also performed with a bulk copper electrode in 1 M NaOH solution containing selenide ion. The deconvolution of the anodic and cathodic I/E profiles corresponding to the electroformation and electroreduction of the Cu-Se film formed allowed us to establish that, depending on the anodic potential limit of the potentiodynamic scan, the Cu-Se phases formed were either a mixture of Cu(2)(-x)Se/Cu(3)Se(2) or Cu(2-x)Se/Cu(3)Se(2)/CuSe. An EQCM study showed that, during the initial stage of Cu-Se phase electroformation, water molecules were released from the electrode. In advanced stages of the process, when the electrode was completely covered by Cu-Se compounds, selenide anions were adsorbed on the formed phase. When the anodic potential limit was extended to -0.2 V, copper oxide compounds were formed. The analysis of the cathodic charge related to Cu-Se phase electroreduction and Energy Dispersive X-ray Spectroscopy (EDXS) analysis confirmed that when the anodic limit was -0.8 V, a mixture of different Cu-Se phases was formed. A I/t transient study performed with a bulk copper electrode in alkaline solution containing selenide established that the nucleation and growth mechanism (NGM) of the Cu-Se phases takes place through an initial bidimensional-instantaneous nucleation (IN2D), followed by four bidimensional-progressive nucleations (PN2D). These results and atomic force microscopy (AFM) experiences supported that the growth of the Cu-Se films occurs through a layer-by-layer mechanism. 相似文献
7.
Cáceres Gustavo Rojas Víctor López Silvana Henríquez Rodrigo Grez Paula Schrebler Ricardo Herrera Francisco Pereyra C. Javier Marotti Ricardo E. Navarrete Emilio Muñoz Eduardo 《Journal of Solid State Electrochemistry》2021,25(6):1881-1888
Journal of Solid State Electrochemistry - In this work, the influence of the electrochemical insertion of different alkali ions, e.g., lithium, sodium, and potassium, on the electrochromic... 相似文献
8.
Rojas Víctor Cáceres Gustavo López Silvana Henríquez Rodrigo Grez Paula Schrebler Ricardo Navarrete Emilio Herrera Francisco Caballero Álvaro Gómez-Cámer Juan Luis Aristizábal Juliet Muñoz Eduardo 《Journal of Solid State Electrochemistry》2023,27(4):865-872
Journal of Solid State Electrochemistry - In this work, the performance of copper (II) hexacyanoferrate(III) (CuHCF) as a cathode material for sodium-ion batteries was studied. The compound was... 相似文献
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