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Ionics

, Volume 25, Issue 6, pp 2763–2768 | Cite as

Polarization and adsorption effects on the wettability of a gold electrode by lithium, sodium, potassium, and cesium chloride melts

  • Victor P. StepanovEmail author
  • Ekaterina V. Kirillova
Original Paper
  • 42 Downloads

Abstract

To establish the patterns of the wettability of solid surfaces by ionic melts, the wetting energy of a gold electrode by lithium, sodium, potassium, and cesium chloride melts was studied as a function of the electrical potential applied to the electrode. It was established that when the potential was shifted in the positive direction relative to the zero-charge potential of gold in the corresponding melt, the shape of the curve that defined the dependence of the wetting energy on the electrical potential varied according to the salt composition: for lithium and sodium chlorides, the wetting energy increased monotonically, while in potassium and cesium chloride melts there was a maxima. This phenomenon was explained from the standpoint of the mutual polarization of gold and chlorine ions in the place of their direct contact. At a certain electric field strength in the double electric layer and at a certain binding energy of the melt particles, the resultant mutual ion polarization led to the formation of ordered layers of ionic associations (presumably AuCln(n − 1)-) on the anode surface, which shielded the electrode charge.

Keywords

Solid surface Ionic melt Wetting Adsorption Electrical potential 

Notes

Acknowledgements

The authors would like to thank Vovkotrub E.G, PhD for performing the Raman analyses of samples using the facilities in the shared access center “Composition of compounds” IHTE, UB RAS.

Funding information

This work was partially funded by programs of the Ural Branch of the RAS (project 18-5-3-12).

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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Institute of High-Temperature Electrochemistry, Ural BranchRussian Academy of SciencesYekaterinburgRussia

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