Magnetohydrodynamic Effects in Electrodeposition Reactions

This paper will discuss the effect of magnetic fields in electrodeposition reactions. The best studied effect is the magnetohydrodynamic effect which is due to the Lorentz force. In general Lorentz forces are generated in the electrolyte where the cross product of current density and magnetic flux density is different from zero. At places where the curl of this force density does not vanish a flow is driven. This in turn causes an increased mass transport and thus higher deposition rates in an electroplating cell. Of course the magnetically driven flow will always interact with other types of convective flows in the cell, e.g. the natural convection.

By tailoring the magnetic field (e.g. via its gradient) the uniformity of electroplated layers can be enhanced [1]. Also the structure of deposits (e.g. in the case of nickel fine-grained vs. coarse-grained) can be affected by the magnetic field [2]. Corresponding examples from the author's labs will be discussed in this paper.

In this contribution we will also show that numerical simulation is a powerful tool if one wants to harvest the full potential of magnetic flow control in electrochemical reactions.

References

[1] S. Mühlenhoff, G. Mutschke, M. Uhlemann, X. Yang, S. Odenbach, J. Fröhlich, K. Eckert. Electrochem. Commun. 36 (2013) 80.

[2] A. Ispas, H. Matsushima, A. Bund, B. Bozzini. J. Electroanal. Chem. 626 (2009) 174.