The effect of the electrode surface roughness at low level of coarseness on the polarization characteristics of electrochemical processes

In this study, it is considered: (a) the effect of the exchange current density to the limiting diffusion current density ratio (j0/jL) at low level of surface coarseness on the polarization characteristics of the electrochemical process, (b) the effect of the shape of surface protrusions on the electrode surface roughness, and (c) the effect of surface roughness on the j0/jL ratio. It was shown that the increase of the value of the j0/jL ratio produces a decrease of overpotential at fixed value of current density. At selected set of conditions, the j0/jL ratio can be increased by the increase of roughness of electrode surface by electrodeposition of disperse deposits at low level of coarseness. The increase of the value of the j0/jL ratio produces large saving of energy required for the evaluation of electrochemical reaction. The conditions in which the electrochemical process can become Ohmic controlled were also specified.