Characteristics of surfaces produced via magnetoelectrolytic deposition

Magneto-electrolytic deposition (MED) is defined as the formation of a substance layer on an appropriate substrate in externally imposed magnetic fields, or in coupled electric and magnetic fields (i.e.,, via magneto-electrolysis). The beneficial effect of magnetic fields on macroscopic properties, e.g., compactness and deposit uniformity, has been known for nearly a century, and the effect on micro-scale behavior, e.g., growth orientation, has been essentially verified in a quantitative sense within the last two decades. Depending on cell geometry, the deposited films are either three-dimensional (3D), or two-dimensional (2D) in a fractal-structure sense, and they can be ferromagnetic (e.g., Ni), paramagnetic (e.g., Cu, Ag, Pb, Zn), or diamagnetic (e.g., conducting polymers). The paper reviews representative experimental data in each magnetic category on certain surface characteristics (e.g., growth-orientation) produced solely by magnetic field imposition, or by the combination of electric and magnetic fields. It also provides certain elementary concepts in the underpinning theories whose various aspects have been employed by researchers to account for experimental findings. It is shown that a need exists for the development of a cogent theoretical framework to understand fully the wealth of experimental phenomena in terms of fundamental concepts of pertinent theories. (C) 2001 Elsevier Science Ltd. All rights reserved.