Simultaneous Spatial and Temporal Measurements of the Current Distribution in a Miniature Hull Cell

Abstract

Experimental validation of the current distribution for actual cell geometries is an important complement to modeling. In this work, the combination of a segmented electrode in a miniaturized Hull Cell with a synchronous monitoring of the current response in each segment is proposed as a novel experimental set-up. The high frequency monitoring of the current response to potential steps is investigated as a mean to access the temporal and spatial evolution of current distribution. The corresponding primary current distribution was measured using a ferricyanide/ferrocyanide alkaline electrolyte, confirming the prediction from Laplace's equation. In addition, the experimental set-up allowed the identification of the transition time from primary to tertiary current distribution regimes.

Theory of Faradaically Modulated Redox Active Electrodes for Electrochemically Mediated Selective Adsorption Processes

“…However, it is very challenging to measure the spatially and temporally dependent concentration profiles experimentally. Spatial current densities are relatively easier accessible signals if spatially segmented electrodes are utilized [67]; such measurements would add another dimension of information and indicate the mass transport progress (especially for the target anions) within the ion adsorption cell, which would be difficult to obtain otherwise. To visualize this approach, the anode was segmented to consist of six electrodes distributed over the channel length.…”