Capacitance of the double electrical layer on the copper-group metals in molten alkali metal halides

被引:8
作者
Kirillova E.V. [1 ]
Stepanov V.P. [1 ,2 ]
机构
[1] Institute of High-Temperature Electrochemistry, Ural Branch, Russian Academy of Sciences, ul. Akademicheskaya 20, Yekaterinburg
[2] Ural Federal University, ul. Mira 19, Yekaterinburg
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D O I
10.1134/S0036029516020051
中图分类号
学科分类号
摘要
The electrochemical impedance is measured to study the capacitance of the double electrical layer of metallic Au, Ag, and Cu as a function of potential and temperature in nine molten salts, namely, the chlorides, bromides, and iodides of sodium, potassium, and cesium. The C–E curve of a gold electrode has an additional minimum in the anodic branch. This minimum for silver is less pronounced and is only observed at low ac signal frequencies in cesium halides. The additional minimum is not detected for copper in any salt under study. This phenomenon is explained on the assumption that the adsorption of halide anions on a positively charged electrode surface has a predominantly chemical rather than an electrostatic character. The specific adsorption in this case is accompanied by charge transfer through the interface and the formation of an adsorbent–adsorbate covalent bond. © 2016, Pleiades Publishing, Ltd.
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页码:691 / 697
页数:6
相关论文
共 40 条
[1]  
Ukshe E.A., Bukun N.G., Leikis D.I., Frumkin A.N., Investigation of the electric double layer in salt melt, Electrochim. Acta, 9, 4, pp. 431-439, (1964)
[2]  
Ukshe E.A., Bukun N.G., The electrical double layer in molten halides, J. Electroanal. Chem., 32, 2, pp. 283-291, (1971)
[3]  
Graves A.D., The electrical double layer in molten salts: Part 1. The potential of zero charge, J. Electroanal. Chem., 25, 3, pp. 349-356, (1970)
[4]  
Graves A.D., Inman D.J., The electrical double layer in molten salts: Part 2. The double-layer capacitance, J. Electroanal. Chem., 25, 3, pp. 357-372, (1970)
[5]  
Tumanova N.K., Delimarskii Y.K., Adsorption of organic substances and double-layer structure at the solid electrode–molten salt interface, Electrochim. Acta, 26, 12, pp. 1737-1741, (1981)
[6]  
Delimarsky Y.K., Tumanova N.K., A study of the effect of surfactants on electrode processes in molten salts, Electrochim. Acta, 24, 1, pp. 19-24, (1979)
[7]  
Dokashenko S.I., Stepanov V.P., Structure of the double electrical layer on liquid metallic electrodes in individual alkali metal halide melts, Elektrokhimiya, 29, 11, pp. 1301-1305, (1993)
[8]  
Dogonadze R.R., Chizmadzhev Y.A., Structure and capacitance of the metal–molten slat interface, Dokl. Akad. Nauk SSSR, 157, 4, pp. 944-947, (1964)
[9]  
Sotnikov A.I., Esin O.A., Alternating structure of the double electrical layer in molten salts, Proceedings of the 3rd All-Union Conference on Physical Chemistry and Electrochemistry of Melts, Salts, and Slags, pp. 209-214, (1968)
[10]  
Lockett V., Sedev R., Ralston J., Rodopoulos T., Horne M., Differential capacitance of the electrical double layer in imidazolium-based ionic liquids: influence of potential, cation size, and temperature, J. Phys. Chem., 112, 19, pp. 7486-7495, (2008)