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Title: Nonlinear Dynamics of Coupled Nickel Electrodissolution with Hydrogen Ion Reduction with Bipolar Electrodes
We investigate the emergence of current oscillations of a bipolar electrode (BPE) in coupled anode/cathode reaction under potentiostatic condition. In a traditional three-electrode setup, the nickel dissolution in sulfuric acid requires a minimum amount of IR ohmic drop, and thus series resistance for the oscillations to occur. In this paper, it is shown that in bipolar setup, when the nickel electrodissolution on the anodic side is coupled to hydrogen ion reduction on the cathodic side, spontaneous current oscillations can occur. An electrochemical analysis of the dynamics shows that the required circuit potential for the oscillations can be predicted from estimating the overpotentials needed for the anodic and cathodic reactions, the driving electrode, and the ohmic drop in the electrolyte. The dynamics and range of oscillations can be tuned by different concentrations of electrolyte, on both the anodic and the cathodic sides. In the considered example, the charge transfer resistance of the cathodic reaction can provide sufficient total resistance even when the solution resistance does not yield sufficient IR drop for the oscillations. Our findings have the potential to promote further studies of the collective behavior of electrochemical reactions using multielectrode arrays in bipolar electrode setups.  more » « less
Award ID(s):
1900011
PAR ID:
10557368
Author(s) / Creator(s):
;
Publisher / Repository:
ECS
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
170
Issue:
11
ISSN:
0013-4651
Page Range / eLocation ID:
113505
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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